Ubuntu Manpage: duplicity - Encrypted incremental backup to local or remote storage.

Provided by: duplicity_0.8.21-1build1_amd64

NAME

       duplicity - Encrypted incremental backup to local or remote storage.

SYNOPSIS

       For detailed descriptions for each command see chapter ACTIONS.

       duplicity [full|incremental] [options] source_directory target_url

       duplicity verify [options] [--compare-data] [--file-to-restore <relpath>] [--time time]
       source_url target_directory

       duplicity collection-status [options] [--file-changed <relpath>] target_url

       duplicity list-current-files [options] [--time time] target_url

       duplicity [restore] [options] [--file-to-restore <relpath>] [--time time] source_url
       target_directory

       duplicity remove-older-than <time> [options] [--force] target_url

       duplicity remove-all-but-n-full <count> [options] [--force] target_url

       duplicity remove-all-inc-of-but-n-full <count> [options] [--force] target_url

       duplicity cleanup [options] [--force] target_url

       duplicity replicate [options] [--time time] source_url target_url

DESCRIPTION

       Duplicity incrementally backs up files and folders into tar-format volumes encrypted with
       GnuPG and places them to a remote (or local) storage backend.  See chapter URL FORMAT for
       a list of all supported backends and how to address them.  Because duplicity uses
       librsync, incremental backups are space efficient and only record the parts of files that
       have changed since the last backup.  Currently duplicity supports deleted files, full Unix
       permissions, uid/gid, directories, symbolic links, fifos, etc., but not hard links.

       If you are backing up the root directory /, remember to --exclude /proc, or else duplicity
       will probably crash on the weird stuff in there.

EXAMPLES

       Here is an example of a backup, using sftp to back up /home/me to some_dir on the
       other.host machine:

              duplicity /home/me sftp://uid@other.host/some_dir

       If the above is run repeatedly, the first will be a full backup, and subsequent ones will
       be incremental. To force a full backup, use the full action:

              duplicity full /home/me sftp://uid@other.host/some_dir

       or enforcing a full every other time via --full-if-older-than <time> , e.g. a full every
       month:

              duplicity --full-if-older-than 1M /home/me sftp://uid@other.host/some_dir

       Now suppose we accidentally delete /home/me and want to restore it the way it was at the
       time of last backup:

              duplicity sftp://uid@other.host/some_dir /home/me

       Duplicity enters restore mode because the URL comes before the local directory.  If we
       wanted to restore just the file "Mail/article" in /home/me as it was three days ago into
       /home/me/restored_file:

              duplicity -t 3D --file-to-restore Mail/article sftp://uid@other.host/some_dir
              /home/me/restored_file

       The following command compares the latest backup with the current files:

              duplicity verify sftp://uid@other.host/some_dir /home/me

       Finally, duplicity recognizes several include/exclude options.  For instance, the
       following will backup the root directory, but exclude /mnt, /tmp, and /proc:

              duplicity --exclude /mnt --exclude /tmp --exclude /proc / file:///usr/local/backup

       Note that in this case the destination is the local directory /usr/local/backup.  The
       following will backup only the /home and /etc directories under root:

              duplicity --include /home --include /etc --exclude '**' / file:///usr/local/backup

       Duplicity can also access a repository via ftp.  If a user name is given, the environment
       variable FTP_PASSWORD is read to determine the password:

              FTP_PASSWORD=mypassword duplicity /local/dir ftp://user@other.host/some_dir

ACTIONS

       Duplicity knows action commands, which can be finetuned with options.
       The actions for backup (full,incr) and restoration (restore) can as well be left out as
       duplicity detects in what mode it should switch to by the order of target URL and local
       folder. If the target URL comes before the local folder a restore is in order, is the
       local folder before target URL then this folder is about to be backed up to the target
       URL.
       If a backup is in order and old signatures can be found duplicity automatically performs
       an incremental backup.

       Note: The following explanations explain some but not all options that can be used in
       connection with that action command.  Consult the OPTIONS section for more detailed
       informations.

       full <folder> <url>
              Perform a full backup. A new backup chain is started even if signatures are
              available for an incremental backup.

       incr <folder> <url>
              If this is requested an incremental backup will be performed.  Duplicity will abort
              if no old signatures can be found.

       verify [--compare-data] [--time <time>] [--file-to-restore <rel_path>] <url> <local_path>
              Verify tests the integrity of the backup archives at the remote location by
              downloading each file and checking both that it can restore the archive and that
              the restored file matches the signature of that file stored in the backup, i.e.
              compares the archived file with its hash value from archival time. Verify does not
              actually restore and will not overwrite any local files. Duplicity will exit with a
              non-zero error level if any files do not match the signature stored in the archive
              for that file. On verbosity level 4 or higher, it will log a message for each file
              that differs from the stored signature. Files must be downloaded to the local
              machine in order to compare them.  Verify does not compare the backed-up version of
              the file to the current local copy of the files unless the --compare-data option is
              used (see below).
              The --file-to-restore option restricts verify to that file or folder.  The --time
              option allows to select a backup to verify.  The --compare-data option enables data
              comparison (see below).

       collection-status [--file-changed <relpath>]<url>
              Summarize the status of the backup repository by printing the chains and sets
              found, and the number of volumes in each.

       list-current-files [--time <time>] <url>
              Lists the files contained in the most current backup or backup at time.  The
              information will be extracted from the signature files, not the archive data
              itself. Thus the whole archive does not have to be downloaded, but on the other
              hand if the archive has been deleted or corrupted, this command will not detect it.

       restore [--file-to-restore <relpath>] [--time <time>] <url> <target_folder>
              You can restore the full monty or selected folders/files from a specific time.  Use
              the relative path as it is printed by list-current-files.  Usually not needed as
              duplicity enters restore mode when it detects that the URL comes before the local
              folder.

       remove-older-than <time> [--force] <url>
              Delete all backup sets older than the given time.  Old backup sets will not be
              deleted if backup sets newer than time depend on them.  See the TIME FORMATS
              section for more information.  Note, this action cannot be combined with backup or
              other actions, such as cleanup.  Note also that --force will be needed to delete
              the files instead of just listing them.

       remove-all-but-n-full <count> [--force] <url>
              Delete all backups sets that are older than the count:th last full backup (in other
              words, keep the last count full backups and associated incremental sets).  count
              must be larger than zero. A value of 1 means that only the single most recent
              backup chain will be kept.  Note that --force will be needed to delete the files
              instead of just listing them.

       remove-all-inc-of-but-n-full <count> [--force] <url>
              Delete incremental sets of all backups sets that are older than the count:th last
              full backup (in other words, keep only old full backups and not their increments).
              count must be larger than zero. A value of 1 means that only the single most recent
              backup chain will be kept intact.  Note that --force will be needed to delete the
              files instead of just listing them.

       cleanup [--force] <url>
              Delete the extraneous duplicity files on the given backend.  Non-duplicity files,
              or files in complete data sets will not be deleted.  This should only be necessary
              after a duplicity session fails or is aborted prematurely.  Note that --force will
              be needed to delete the files instead of just listing them.

       replicate [--time time] <source_url> <target_url>
              Replicate backup sets from source to target backend. Files will be (re)-encrypted
              and (re)-compressed depending on normal backend options. Signatures and volumes
              will not get recomputed, thus options like --volsize or --max-blocksize have no
              effect.  When --time time is given, only backup sets older than time will be
              replicated.

OPTIONS

--allow-source-mismatch
Do not abort on attempts to use the same archive dir or remote backend to back up
different directories. duplicity will tell you if you need this switch.

--archive-dir path
The archive directory. NOTE: This option changed in 0.6.0. The archive directory
is now necessary in order to manage persistence for current and future
enhancements. As such, this option is now used only to change the location of the
archive directory. The archive directory should not be deleted, or duplicity will
have to recreate it from the remote repository (which may require decrypting the
backup contents).

When backing up or restoring, this option specifies that the local archive
directory is to be created in path. If the archive directory is not specified, the
default will be to create the archive directory in ~/.cache/duplicity/.

The archive directory can be shared between backups to multiple targets, because a
subdirectory of the archive dir is used for individual backups (see --name ).

The combination of archive directory and backup name must be unique in order to
separate the data of different backups.

The interaction between the --archive-dir and the --name options allows for four
possible combinations for the location of the archive dir:

1. neither specified (default)
~/.cache/duplicity/hash-of-url

2. --archive-dir=/arch, no --name
/arch/hash-of-url

3. no --archive-dir, --name=foo
~/.cache/duplicity/foo

4. --archive-dir=/arch, --name=foo
/arch/foo

--asynchronous-upload
(EXPERIMENTAL) Perform file uploads asynchronously in the background, with respect
to volume creation. This means that duplicity can upload a volume while, at the
same time, preparing the next volume for upload. The intended end-result is a
faster backup, because the local CPU and your bandwidth can be more consistently
utilized. Use of this option implies additional need for disk space in the
temporary storage location; rather than needing to store only one volume at a time,
enough storage space is required to store two volumes.

--backend-retry-delay number
Specifies the number of seconds that duplicity waits after an error has occured
before attempting to repeat the operation.

--cf-backend backend
Allows the explicit selection of a cloudfiles backend. Defaults to pyrax.
Alternatively you might choose cloudfiles.

--b2-hide-files
Causes Duplicity to hide files in B2 instead of deleting them. Useful in
combination with B2's lifecycle rules.

--compare-data
Enable data comparison of regular files on action verify. This conducts a verify as
described above to verify the integrity of the backup archives, but additionally
compares restored files to those in target_directory. Duplicity will not replace
any files in target_directory. Duplicity will exit with a non-zero error level if
the files do not correctly verify or if any files from the archive differ from
those in target_directory. On verbosity level 4 or higher, it will log a message
for each file that differs from its equivalent in target_directory.

--copy-links
Resolve symlinks during backup. Enabling this will resolve & back up the symlink's
file/folder data instead of the symlink itself, potentially increasing the size of
the backup.

--dry-run
Calculate what would be done, but do not perform any backend actions

--encrypt-key key-id
When backing up, encrypt to the given public key, instead of using symmetric
(traditional) encryption. Can be specified multiple times. The key-id can be
given in any of the formats supported by GnuPG; see gpg(1), section "HOW TO SPECIFY
A USER ID" for details.

--encrypt-secret-keyring filename
This option can only be used with --encrypt-key, and changes the path to the secret
keyring for the encrypt key to filename This keyring is not used when creating a
backup. If not specified, the default secret keyring is used which is usually
located at .gnupg/secring.gpg

--encrypt-sign-key key-id
Convenience parameter. Same as --encrypt-key key-id --sign-key key-id.

--exclude shell_pattern
Exclude the file or files matched by shell_pattern. If a directory is matched,
then files under that directory will also be matched. See the FILE SELECTION
section for more information.

--exclude-device-files
Exclude all device files. This can be useful for security/permissions reasons or
if duplicity is not handling device files correctly.

--exclude-filelist filename
Excludes the files listed in filename, with each line of the filelist interpreted
according to the same rules as --include and --exclude. See the FILE SELECTION
section for more information.

--exclude-if-present filename
Exclude directories if filename is present. Allows the user to specify folders that
they do not wish to backup by adding a specified file (e.g. ".nobackup") instead of
maintaining a comprehensive exclude/include list.

--exclude-older-than time
Exclude any files whose modification date is earlier than the specified time. This
can be used to produce a partial backup that contains only recently changed files.
See the TIME FORMATS section for more information.

--exclude-other-filesystems
Exclude files on file systems (identified by device number) other than the file
system the root of the source directory is on.

--exclude-regexp regexp
Exclude files matching the given regexp. Unlike the --exclude option, this option
does not match files in a directory it matches. See the FILE SELECTION section for
more information.

--file-prefix, --file-prefix-manifest, --file-prefix-archive, --file-prefix-signature
Adds a prefix to all files, manifest files, archive files, and/or signature files.

The same set of prefixes must be passed in on backup and restore.

If both global and type-specific prefixes are set, global prefix will go before
type-specific prefixes.

See also A NOTE ON AMAZON S3 below.

--s3-unencrypted-connection
Don't use SSL for connections to S3.

This may be much faster, at some cost to confidentiality.

With this option, anyone who can observe traffic between your computer and S3 will
be able to tell: that you are using Duplicity, the name of the bucket, your AWS
Access Key ID, the increment dates and the amount of data in each increment.

This option affects only the connection, not the GPG encryption of the backup
increment files. Unless that is disabled, an observer will not be able to see the
file names or contents.

This option is not available when using the newer boto3 backend.

See also A NOTE ON AMAZON S3 below.

--s3-use-new-style
When operating on Amazon S3 buckets, use new-style subdomain bucket addressing.
This is now the preferred method to access Amazon S3, but is not backwards
compatible if your bucket name contains upper-case characters or other characters
that are not valid in a hostname.

This option has no effect when using the newer boto3 backend, which will always use
new style subdomain bucket naming.

See also A NOTE ON AMAZON S3 below.

--s3-use-rrs
Store volumes using Reduced Redundancy Storage when uploading to Amazon S3. This
will lower the cost of storage but also lower the durability of stored volumes to
99.99% instead the 99.999999999% durability offered by Standard Storage on S3.

--s3-use-ia
Store volumes using Standard - Infrequent Access when uploading to Amazon S3. This
storage class has a lower storage cost but a higher per-request cost, and the
storage cost is calculated against a 30-day storage minimum. According to Amazon,
this storage is ideal for long-term file storage, backups, and disaster recovery.

--s3-use-onezone-ia
Store volumes using One Zone - Infrequent Access when uploading to Amazon S3. This
storage is similar to Standard - Infrequent Access, but only stores object data in
one Availability Zone.

--s3-use-glacier
Store volumes using Glacier S3 when uploading to Amazon S3. This storage class has
a lower cost of storage but a higher per-request cost along with delays of up to 12
hours from the time of retrieval request. This storage cost is calculated against a
90-day storage minimum. According to Amazon this storage is ideal for data
archiving and long-term backup offering 99.999999999% durability. To restore a
backup you will have to manually migrate all data stored on AWS Glacier back to
Standard S3 and wait for AWS to complete the migration. Notice: Duplicity will
store the manifest.gpg files from full and incremental backups on AWS S3 standard
storage to allow quick retrieval for later incremental backups, all other data is
stored in S3 Glacier.

--s3-use-deep-archive
Store volumes using Glacier Deep Archive S3 when uploading to Amazon S3. This
storage class has a lower cost of storage but a higher per-request cost along with
delays of up to 48 hours from the time of retrieval request. This storage cost is
calculated against a 180-day storage minimum. According to Amazon this storage is
ideal for data archiving and long-term backup offering 99.999999999% durability.
To restore a backup you will have to manually migrate all data stored on AWS
Glacier Deep Archive back to Standard S3 and wait for AWS to complete the
migration. Notice: Duplicity will store the manifest.gpg files from full and
incremental backups on AWS S3 standard storage to allow quick retrieval for later
incremental backups, all other data is stored in S3 Glacier Deep Archive.

Glacier Deep Archive is only available when using the newer boto3 backend.

--s3-use-multiprocessing
Allow multipart volumne uploads to S3 through multiprocessing. This option requires
Python 2.6 and can be used to make uploads to S3 more efficient. If enabled, files
duplicity uploads to S3 will be split into chunks and uploaded in parallel. Useful
if you want to saturate your bandwidth or if large files are failing during upload.

This has no effect when using the newer boto3 backend. Boto3 always attempts to
multiprocessing when it is believed it will be more efficient.

See also A NOTE ON AMAZON S3 below.

--s3-use-server-side-encryption
Allow use of server side encryption in S3

--s3-multipart-chunk-size
Chunk size (in MB) used for S3 multipart uploads. Make this smaller than --volsize
to maximize the use of your bandwidth. For example, a chunk size of 10MB with a
volsize of 30MB will result in 3 chunks per volume upload.

See also A NOTE ON AMAZON S3 below.

--s3-multipart-max-procs
Specify the maximum number of processes to spawn when performing a multipart upload
to S3. By default, this will choose the number of processors detected on your
system (e.g. 4 for a 4-core system). You can adjust this number as required to
ensure you don't overload your system while maximizing the use of your bandwidth.

This has no effect when using the newer boto3 backend.

See also A NOTE ON AMAZON S3 below.

--s3-multipart-max-timeout
You can control the maximum time (in seconds) a multipart upload can spend on
uploading a single chunk to S3. This may be useful if you find your system hanging
on multipart uploads or if you'd like to control the time variance when uploading
to S3 to ensure you kill connections to slow S3 endpoints.

This has no effect when using the newer boto3 backend.

See also A NOTE ON AMAZON S3 below.

--s3-region-name
Specifies the region of the S3 storage.

This is currently only used in the newer boto3 backend.

--s3-endpoint-url
Specifies the endpoint URL of the S3 storage.

This is currently only used in the newer boto3 backend.

--azure-blob-tier
Standard storage tier used for backup files (Hot|Cool|Archive).

--azure-max-single-put-size
Specify the number of the largest supported upload size where the Azure library
makes only one put call. If the content size is known and below this value the
Azure library will only perform one put request to upload one block. The number is
expected to be in bytes.

--azure-max-block-size
Specify the number for the block size used by the Azure library to upload blobs if
it is split into multiple blocks. The maximum block size the service supports is
104857600 (100MiB) and the default is 4194304 (4MiB)

--azure-max-connections
Specify the number of maximum connections to transfer one blob to Azure blob size
exceeds 64MB. The default values is 2.

--scp-command command
(only ssh pexpect backend with --use-scp enabled) The command will be used instead
of "scp" to send or receive files. To list and delete existing files, the sftp
command is used.
See also A NOTE ON SSH BACKENDS section SSH pexpect backend.

--sftp-command command
(only ssh pexpect backend) The command will be used instead of "sftp".
See also A NOTE ON SSH BACKENDS section SSH pexpect backend.

--short-filenames
If this option is specified, the names of the files duplicity writes will be
shorter (about 30 chars) but less understandable. This may be useful when backing
up to MacOS or another OS or FS that doesn't support long filenames.

--sign-key key-id
This option can be used when backing up, restoring or verifying. When backing up,
all backup files will be signed with keyid key. When restoring, duplicity will
signal an error if any remote file is not signed with the given key-id. The key-id
can be given in any of the formats supported by GnuPG; see gpg(1), section "HOW TO
SPECIFY A USER ID" for details. Should be specified only once because currently
only one signing key is supported. Last entry overrides all other entries.
See also A NOTE ON SYMMETRIC ENCRYPTION AND SIGNING

--ssh-askpass
Tells the ssh backend to prompt the user for the remote system password, if it was
not defined in target url and no FTP_PASSWORD env var is set. This password is
also used for passphrase-protected ssh keys.

--ssh-options options
Allows you to pass options to the ssh backend. Can be specified multiple times or
as a space separated options list. The options list should be of the form
"-oOpt1='parm1' -oOpt2='parm2'" where the option string is quoted and the only
spaces allowed are between options. The option string will be passed verbatim to
both scp and sftp, whose command line syntax differs slightly hence the options
should therefore be given in the long option format described in ssh_config(5).

example of a list:

duplicity --ssh-options="-oProtocol=2 -oIdentityFile='/my/backup/id'" /home/me
scp://user@host/some_dir

example with multiple parameters:

duplicity --ssh-options="-oProtocol=2" --ssh-
options="-oIdentityFile='/my/backup/id'" /home/me scp://user@host/some_dir

NOTE: The ssh paramiko backend currently supports only the -i or -oIdentityFile or
-oUserKnownHostsFile or -oGlobalKnownHostsFile settings. If needed provide more
host specific options via ssh_config file.

--ssl-cacert-file file
(only webdav & lftp backend) Provide a cacert file for ssl certificate
verification.
See also A NOTE ON SSL CERTIFICATE VERIFICATION.

--ssl-cacert-path path/to/certs/
(only webdav backend and python 2.7.9+ OR lftp+webdavs and a recent lftp) Provide a
path to a folder containing cacert files for ssl certificate verification.
See also A NOTE ON SSL CERTIFICATE VERIFICATION.

--ssl-no-check-certificate
(only webdav & lftp backend) Disable ssl certificate verification.
See also A NOTE ON SSL CERTIFICATE VERIFICATION.

--swift-storage-policy
Use this storage policy when operating on Swift containers.
See also A NOTE ON SWIFT (OPENSTACK OBJECT STORAGE) ACCESS.

--metadata-sync-mode mode
This option defaults to 'partial', but you can set it to 'full'
Use 'partial' to avoid syncing metadata for backup chains that you are not going to
use. This saves time when restoring for the first time, and lets you restore an
old backup that was encrypted with a different passphrase by supplying only the
target passphrase.
Use 'full' to sync metadata for all backup chains on the remote.

--tempdir directory
Use this existing directory for duplicity temporary files instead of the system
default, which is usually the /tmp directory. This option supersedes any
environment variable.
See also ENVIRONMENT VARIABLES.

-ttime, --time time, --restore-time time
Specify the time from which to restore or list files.

--time-separator char
Use char as the time separator in filenames instead of colon (":").

--timeout seconds
Use seconds as the socket timeout value if duplicity begins to timeout during
network operations. The default is 30 seconds.

--use-agent
If this option is specified, then --use-agent is passed to the GnuPG encryption
process and it will try to connect to gpg-agent before it asks for a passphrase for
--encrypt-key or --sign-key if needed.
Note: Contrary to previous versions of duplicity, this option will also be honored
by GnuPG 2 and newer versions. If GnuPG 2 is in use, duplicity passes the option
--pinentry-mode=loopback to the the gpg process unless --use-agent is specified on
the duplicity command line. This has the effect that GnuPG 2 uses the agent only if
--use-agent is given, just like GnuPG 1.

--verbosity level, -vlevel
Specify output verbosity level (log level). Named levels and corresponding values
are 0 Error, 2 Warning, 4 Notice (default), 8 Info, 9 Debug (noisiest).
level may also be
a character: e, w, n, i, d
a word: error, warning, notice, info, debug

The options -v4, -vn and -vnotice are functionally equivalent, as are the
mixed/upper-case versions -vN, -vNotice and -vNOTICE.

--version
Print duplicity's version and quit.

--volsize number
Change the volume size to number MB. Default is 200MB.

ENVIRONMENT VARIABLES

       TMPDIR, TEMP, TMP
              In decreasing order of importance, specifies the directory to use for temporary
              files (inherited from Python's tempfile module).  Eventually the option --tempdir
              supercedes any of these.

       FTP_PASSWORD
              Supported by most backends which are password capable. More secure than setting it
              in the backend url (which might be readable in the operating systems process
              listing to other users on the same machine).

       PASSPHRASE
              This passphrase is passed to GnuPG. If this is not set, the user will be prompted
              for the passphrase.

       SIGN_PASSPHRASE
              The passphrase to be used for --sign-key.  If ommitted and sign key is also one of
              the keys to encrypt against PASSPHRASE will be reused instead.  Otherwise, if
              passphrase is needed but not set the user will be prompted for it.

              Other environment variables may be used to configure specific backends.  See the
              notes for the particular backend.

URL FORMAT

       Duplicity uses the URL format (as standard as possible) to define data locations.  The
       generic format for a URL is:

              scheme://[user[:password]@]host[:port]/[/]path

       It is not recommended to expose the password on the command line since it could be
       revealed to anyone with permissions to do process listings, it is permitted however.
       Consider setting the environment variable FTP_PASSWORD instead, which is used by most, if
       not all backends, regardless of it's name.

       In protocols that support it, the path may be preceded by a single slash, '/path', to
       represent a relative path to the target home directory, or preceded by a double slash,
       '//path', to represent an absolute filesystem path.

       Note:
              Scheme (protocol) access may be provided by more than one backend.  In case the
              default backend is buggy or simply not working in a specific case it might be worth
              trying an alternative implementation.  Alternative backends can be selected by
              prefixing the scheme with the name of the alternative backend e.g.  ncftp+ftp://
              and are mentioned below the scheme's syntax summary.

       Formats of each of the URL schemes follow:

       Amazon Drive Backend

              ad://some_dir

              See also A NOTE ON AMAZON DRIVE

       Azure

              azure://container-name

              See also A NOTE ON AZURE ACCESS

       B2

              b2://account_id[:application_key]@bucket_name/[folder/]

       Box

              box:///some_dir[?config=path_to_config]

              See also A NOTE ON BOX ACCESS

       Cloud Files (Rackspace)

              cf+http://container_name

              See also A NOTE ON CLOUD FILES ACCESS

       Dropbox

              dpbx:///some_dir

              Make sure to read A NOTE ON DROPBOX ACCESS first!

       Local file path

              file://[relative|/absolute]/local/path

       FISH (Files transferred over Shell protocol) over ssh

              fish://user[:pwd]@other.host[:port]/[relative|/absolute]_path

       FTP

              ftp[s]://user[:password]@other.host[:port]/some_dir

              NOTE: use lftp+, ncftp+ prefixes to enforce a specific backend, default is
              lftp+ftp://...

       Google Docs

              gdocs://user[:password]@other.host/some_dir

              NOTE: use pydrive+, gdata+ prefixes to enforce a specific backend, default is
              pydrive+gdocs://...

       Google Cloud Storage

              gs://bucket[/prefix]

       HSI

              hsi://user[:password]@other.host/some_dir

       hubiC

              cf+hubic://container_name

              See also A NOTE ON HUBIC

       IMAP email storage

              imap[s]://user[:password]@host.com[/from_address_prefix]

              See also A NOTE ON IMAP

       MEGA.nz cloud storage (only works for accounts created prior to November 2018, uses
       "megatools")

              mega://user[:password]@mega.nz/some_dir

              NOTE: if not given in the URL, relies on password being stored within $HOME/.megarc
              (as used by the "megatools" utilities)

       MEGA.nz cloud storage (works for all MEGA accounts, uses "MEGAcmd" tools)

              megav2://user[:password]@mega.nz/some_dir
              megav3://user[:password]@mega.nz/some_dir[?no_logout=1] (For latest MEGAcmd)

              NOTE: despite "MEGAcmd" no longer uses a configuration file, for convenience
              storing the user password this backend searches it in the $HOME/.megav2rc file
              (same syntax as the old $HOME/.megarc)
                  [Login]
                  Username = MEGA_USERNAME
                  Password = MEGA_PASSWORD

       OneDrive Backend

              onedrive://some_dir

       Par2 Wrapper Backend

              par2+scheme://[user[:password]@]host[:port]/[/]path

              See also A NOTE ON PAR2 WRAPPER BACKEND

       Rclone Backend

              rclone://remote:/some_dir

       See also A NOTE ON RCLONE BACKEND

       Rsync via daemon

              rsync://user[:password]@host.com[:port]::[/]module/some_dir

       Rsync over ssh (only key auth)

              rsync://user@host.com[:port]/[relative|/absolute]_path

       S3 storage (Amazon)

              s3://host[:port]/bucket_name[/prefix]
              s3+http://bucket_name[/prefix]
              defaults to the legacy boto backend based on boto v2 (last update 2018/07)
              alternatively try the newer boto3+s3://bucket_name[/prefix]

              For details see A NOTE ON AMAZON S3 and see also A NOTE ON EUROPEAN S3 BUCKETS
              below.

       SCP/SFTP access

              scp://.. or
              sftp://user[:pwd]@other.host[:port]/[relative|/absolute]_path

              defaults are paramiko+scp:// and paramiko+sftp://
              alternatively try pexpect+scp://, pexpect+sftp://, lftp+sftp://
              See also --ssh-askpass, --ssh-options and A NOTE ON SSH BACKENDS.

       Swift (Openstack)

              swift://container_name[/prefix]

              See also A NOTE ON SWIFT (OPENSTACK OBJECT STORAGE) ACCESS

       Public Cloud Archive (OVH)

              pca://container_name[/prefix]

              See also A NOTE ON PCA ACCESS

       Tahoe-LAFS

              tahoe://alias/directory

       WebDAV

              webdav[s]://user[:password]@other.host[:port]/some_dir

              alternatively try lftp+webdav[s]://

       pydrive

              pydrive://<service account' email address>@developer.gserviceaccount.com/some_dir

              See also A NOTE ON PYDRIVE BACKEND below.

       gdrive

              gdrive://<service account' email address>@developer.gserviceaccount.com/some_dir

              See also A NOTE ON GDRIVE BACKEND below.

       multi

              multi:///path/to/config.json

              See also A NOTE ON MULTI BACKEND below.

       MediaFire

              mf://user[:password]@mediafire.com/some_dir

              See also A NOTE ON MEDIAFIRE BACKEND below.

TIME FORMATS

duplicity uses time strings in two places. Firstly, many of the files duplicity creates
will have the time in their filenames in the w3 datetime format as described in a w3 note
at http://www.w3.org/TR/NOTE-datetime. Basically they look like
"2001-07-15T04:09:38-07:00", which means what it looks like. The "-07:00" section means
the time zone is 7 hours behind UTC.

Secondly, the -t, --time, and --restore-time options take a time string, which can be
given in any of several formats:

1. the string "now" (refers to the current time)

2. a sequences of digits, like "123456890" (indicating the time in seconds after the
epoch)

3. A string like "2002-01-25T07:00:00+02:00" in datetime format

4. An interval, which is a number followed by one of the characters s, m, h, D, W, M,
or Y (indicating seconds, minutes, hours, days, weeks, months, or years
respectively), or a series of such pairs. In this case the string refers to the
time that preceded the current time by the length of the interval. For instance,
"1h78m" indicates the time that was one hour and 78 minutes ago. The calendar here
is unsophisticated: a month is always 30 days, a year is always 365 days, and a day
is always 86400 seconds.

5. A date format of the form YYYY/MM/DD, YYYY-MM-DD, MM/DD/YYYY, or MM-DD-YYYY, which
indicates midnight on the day in question, relative to the current time zone
settings. For instance, "2002/3/5", "03-05-2002", and "2002-3-05" all mean March
5th, 2002.

FILE SELECTION

When duplicity is run, it searches through the given source directory and backs up all the
files specified by the file selection system. The file selection system comprises a
number of file selection conditions, which are set using one of the following command line
options:
--exclude
--exclude-device-files
--exclude-if-present
--exclude-filelist
--exclude-regexp
--include
--include-filelist
--include-regexp
Each file selection condition either matches or doesn't match a given file. A given file
is excluded by the file selection system exactly when the first matching file selection
condition specifies that the file be excluded; otherwise the file is included.

For instance,

duplicity --include /usr --exclude /usr /usr scp://user@host/backup

is exactly the same as

duplicity /usr scp://user@host/backup

because the include and exclude directives match exactly the same files, and the --include
comes first, giving it precedence. Similarly,

duplicity --include /usr/local/bin --exclude /usr/local /usr scp://user@host/backup

would backup the /usr/local/bin directory (and its contents), but not /usr/local/doc.

The include, exclude, include-filelist, and exclude-filelist options accept some extended
shell globbing patterns. These patterns can contain *, **, ?, and [...] (character
ranges). As in a normal shell, * can be expanded to any string of characters not
containing "/", ? expands to any character except "/", and [...] expands to a single
character of those characters specified (ranges are acceptable). The new special pattern,
**, expands to any string of characters whether or not it contains "/". Furthermore, if
the pattern starts with "ignorecase:" (case insensitive), then this prefix will be removed
and any character in the string can be replaced with an upper- or lowercase version of
itself.

Remember that you may need to quote these characters when typing them into a shell, so the
shell does not interpret the globbing patterns before duplicity sees them.

The --exclude pattern option matches a file if:

1. pattern can be expanded into the file's filename, or
2. the file is inside a directory matched by the option.

Conversely, the --include pattern matches a file if:

1. pattern can be expanded into the file's filename, or
2. the file is inside a directory matched by the option, or
3. the file is a directory which contains a file matched by the option.

For example,

--exclude /usr/local

matches e.g. /usr/local, /usr/local/lib, and /usr/local/lib/netscape. It is the same as
--exclude /usr/local --exclude '/usr/local/**'.

On the other hand

--include /usr/local

specifies that /usr, /usr/local, /usr/local/lib, and /usr/local/lib/netscape (but not
/usr/doc) all be backed up. Thus you don't have to worry about including parent
directories to make sure that included subdirectories have somewhere to go.

Finally,

--include ignorecase:'/usr/[a-z0-9]foo/*/**.py'

would match a file like /usR/5fOO/hello/there/world.py. If it did match anything, it
would also match /usr. If there is no existing file that the given pattern can be
expanded into, the option will not match /usr alone.

The --include-filelist, and --exclude-filelist, options also introduce file selection
conditions. They direct duplicity to read in a text file (either ASCII or UTF-8), each
line of which is a file specification, and to include or exclude the matching files.
Lines are separated by newlines or nulls, depending on whether the --null-separator switch
was given. Each line in the filelist will be interpreted as a globbing pattern the way
--include and --exclude options are interpreted, except that lines starting with "+ " are
interpreted as include directives, even if found in a filelist referenced by --exclude-
filelist. Similarly, lines starting with "- " exclude files even if they are found within
an include filelist.

For example, if file "list.txt" contains the lines:

/usr/local
- /usr/local/doc
/usr/local/bin
+ /var
- /var

then --include-filelist list.txt would include /usr, /usr/local, and /usr/local/bin. It
would exclude /usr/local/doc, /usr/local/doc/python, etc. It would also include
/usr/local/man, as this is included within /user/local. Finally, it is undefined what
happens with /var. A single file list should not contain conflicting file specifications.

Each line in the filelist will also be interpreted as a globbing pattern the way --include
and --exclude options are interpreted. For instance, if the file "list.txt" contains the
lines:

dir/foo
+ dir/bar
- **

Then --include-filelist list.txt would be exactly the same as specifying --include dir/foo
--include dir/bar --exclude ** on the command line.

Finally, the --include-regexp and --exclude-regexp options allow files to be included and
excluded if their filenames match a python regular expression. Regular expression syntax
is too complicated to explain here, but is covered in Python's library reference. Unlike
the --include and --exclude options, the regular expression options don't match files
containing or contained in matched files. So for instance

--include '[0-9]{7}(?!foo)'

matches any files whose full pathnames contain 7 consecutive digits which aren't followed
by 'foo'. However, it wouldn't match /home even if /home/ben/1234567 existed.

A NOTE ON AMAZON DRIVE

       1.     The API Keys used for Amazon Drive have not been granted production limits.  Amazon
              do not say what the development limits are and are not replying to to requests to
              whitelist duplicity. A related tool, acd_cli, was demoted to development limits,
              but continues to work fine except for cases of excessive usage. If you experience
              throttling and similar issues with Amazon Drive using this backend, please report
              them to the mailing list.

       2.     If you previously used the acd+acdcli backend, it is strongly recommended to update
              to the ad backend instead, since it interfaces directly with Amazon Drive. You will
              need to setup the OAuth once again, but can otherwise keep your backups and config.

A NOTE ON AMAZON S3

When backing up to Amazon S3, two backend implementations are available. The schemes "s3"
and "s3+http" are implemented using the older boto library, which has been deprecated and
is no longer supported. The "boto3+s3" scheme is based on the newer boto3 library. This
new backend fixes several known limitations in the older backend, which have crept in as
Amazon S3 has evolved while the deprecated boto library has not kept up.

The boto3 backend should behave largely the same as the older S3 backend, but there are
some differences in the handling of some of the "S3" options. Additionally, there are
some compatibility differences with the new backed. Because of these reasons, both
backends have been retained for the time being. See the documentation for specific
options regarding differences related to each backend.

The boto3 backend does not support bucket creation. This is a deliberate choice which
simplifies the code, and side steps problems related to region selection. Additionally,
it is probably not a good practice to give your backup role bucket creation rights. In
most cases the role used for backups should probably be limited to specific buckets.

The boto3 backend only supports newer domain style buckets. Amazon is moving to deprecate
the older bucket style, so migration is recommended. Use the older s3 backend for
compatibility with backups stored in buckets using older naming conventions.

The boto3 backend does not currently support initiating restores from the glacier storage
class. When restoring a backup from glacier or glacier deep archive, the backup files
must first be restored out of band. There are multiple options when restoring backups
from cold storage, which vary in both cost and speed. See Amazon's documentation for
details.

A NOTE ON AZURE ACCESS

       The Azure backend requires the Microsoft Azure Storage Blobs client library for Python to
       be installed on the system.  See REQUIREMENTS.

       It uses the environment variable AZURE_CONNECTION_STRING (required).  This string contains
       all necessary information such as Storage Account name and the key for authentication.
       You can find it under Access Keys for the storage account.

       Duplicity will take care to create the container when performing the backup.  Do not
       create it manually before.

       A container name (as given as the backup url) must be a valid DNS name, conforming to the
       following naming rules:

              1.     Container names must start with a letter or number, and can contain only
                     letters, numbers, and the dash (-) character.

              2.     Every dash (-) character must be immediately preceded and followed by a
                     letter or number; consecutive dashes are not permitted in container names.

              3.     All letters in a container name must be lowercase.

              4.     Container names must be from 3 through 63 characters long.

       These rules come from Azure; see https://docs.microsoft.com/en-
       us/rest/api/storageservices/naming-and-referencing-containers--blobs--and-metadata

A NOTE ON BOX ACCESS

       The box backend requires boxsdk with jwt support to be installed on the system.  See
       REQUIREMENTS.

       It uses the environment variable BOX_CONFIG_PATH (optional).  This string contains the
       path to box custom app's config.json. Either this environment variable or the config query
       parameter in the url need to be specified, if both are specified, query paramter takes
       precedence.

   Create a Box custom app
       In order to use box backend, user need to create a box custom app in the box developer
       console (https://app.box.com/developers/console).

       After create a new custom app, please make sure it is configured as follow:

              1.     Choose "App Access Only" for "App Access Level"

              2.     Check "Write all files and folders stored in Box"

              3.     Generate a Public/Private Keypair

       The user also need to grant the created custom app permission in the admin console
       (https://app.box.com/master/custom-apps) by clicking the "+" button and enter the
       client_id which can be found on the custom app's configuration page.

A NOTE ON CLOUD FILES ACCESS

       Pyrax is Rackspace's next-generation Cloud management API, including Cloud Files access.
       The cfpyrax backend requires the pyrax library to be installed on the system.  See
       REQUIREMENTS.

       Cloudfiles is Rackspace's now deprecated implementation of OpenStack Object Storage
       protocol.  Users wishing to use Duplicity with Rackspace Cloud Files should migrate to the
       new Pyrax plugin to ensure support.

       The backend requires python-cloudfiles to be installed on the system.  See REQUIREMENTS.

       It uses three environment variables for authentification: CLOUDFILES_USERNAME (required),
       CLOUDFILES_APIKEY (required), CLOUDFILES_AUTHURL (optional)

       If CLOUDFILES_AUTHURL is unspecified it will default to the value provided by python-
       cloudfiles, which points to rackspace, hence this value must be set in order to use other
       cloud files providers.

A NOTE ON DROPBOX ACCESS

1. First of all Dropbox backend requires valid authentication token. It should be
passed via DPBX_ACCESS_TOKEN environment variable.
To obtain it please create 'Dropbox API' application at:
https://www.dropbox.com/developers/apps/create
Then visit app settings and just use 'Generated access token' under OAuth2 section.
Alternatively you can let duplicity generate access token itself. In such case
temporary export DPBX_APP_KEY , DPBX_APP_SECRET using values from app settings page
and run duplicity interactively.
It will print the URL that you need to open in the browser to obtain OAuth2 token
for the application. Just follow on-screen instructions and then put generated
token to DPBX_ACCESS_TOKEN variable. Once done, feel free to unset DPBX_APP_KEY and
DPBX_APP_SECRET

2. "some_dir" must already exist in the Dropbox folder. Depending on access token kind
it may be:
Full Dropbox: path is absolute and starts from 'Dropbox' root folder.
App Folder: path is related to application folder. Dropbox client will show
it in ~/Dropbox/Apps/<app-name>

3. When using Dropbox for storage, be aware that all files, including the ones in the
Apps folder, will be synced to all connected computers. You may prefer to use a
separate Dropbox account specially for the backups, and not connect any computers
to that account. Alternatively you can configure selective sync on all computers to
avoid syncing of backup files

A NOTE ON EUROPEAN S3 BUCKETS

Amazon S3 provides the ability to choose the location of a bucket upon its creation. The
purpose is to enable the user to choose a location which is better located network
topologically relative to the user, because it may allow for faster data transfers.

duplicity will create a new bucket the first time a bucket access is attempted. At this
point, the bucket will be created in Europe if --s3-european-buckets was given. For
reasons having to do with how the Amazon S3 service works, this also requires the use of
the --s3-use-new-style option. This option turns on subdomain based bucket addressing in
S3. The details are beyond the scope of this man page, but it is important to know that
your bucket must not contain upper case letters or any other characters that are not valid
parts of a hostname. Consequently, for reasons of backwards compatibility, use of
subdomain based bucket addressing is not enabled by default.

Note that you will need to use --s3-use-new-style for all operations on European buckets;
not just upon initial creation.

You only need to use --s3-european-buckets upon initial creation, but you may may use it
at all times for consistency.

Further note that when creating a new European bucket, it can take a while before the
bucket is fully accessible. At the time of this writing it is unclear to what extent this
is an expected feature of Amazon S3, but in practice you may experience timeouts, socket
errors or HTTP errors when trying to upload files to your newly created bucket. Give it a
few minutes and the bucket should function normally.

A NOTE ON FILENAME PREFIXES

       Filename prefixes can be used in multi backend with mirror mode to define affinity rules.
       They can also be used in conjunction with S3 lifecycle rules to transition archive files
       to Glacier, while keeping metadata (signature and manifest files) on S3.

       Duplicity does not require access to archive files except when restoring from backup.

A NOTE ON GOOGLE CLOUD STORAGE

       Support for Google Cloud Storage relies on its Interoperable Access, which must be enabled
       for your account.  Once enabled, you can generate Interoperable Storage Access Keys and
       pass them to duplicity via the GS_ACCESS_KEY_ID and GS_SECRET_ACCESS_KEY environment
       variables. Alternatively, you can run gsutil config -a to have the Google Cloud Storage
       utility populate the ~/.boto configuration file.

       Enable Interoperable Access: https://code.google.com/apis/console#:storage
       Create Access Keys: https://code.google.com/apis/console#:storage:legacy

A NOTE ON HUBIC

       The hubic backend requires the pyrax library to be installed on the system. See
       REQUIREMENTS.  You will need to set your credentials for hubiC in a file called
       ~/.hubic_credentials, following this pattern:

              [hubic]
              email = your_email
              password = your_password
              client_id = api_client_id
              client_secret = api_secret_key
              redirect_uri = http://localhost/

A NOTE ON IMAP

       An IMAP account can be used as a target for the upload.  The userid may be specified and
       the password will be requested.

       The from_address_prefix may be specified (and probably should be). The text will be used
       as the "From" address in the IMAP server.  Then on a restore (or list) command the
       from_address_prefix will distinguish between different backups.

A NOTE ON MULTI BACKEND

The multi backend allows duplicity to combine the storage available in more than one
backend store (e.g., you can store across a google drive account and a onedrive account to
get effectively the combined storage available in both). The URL path specifies a JSON
formated config file containing a list of the backends it will use. The URL may also
specify "query" parameters to configure overall behavior. Each element of the list must
have a "url" element, and may also contain an optional "description" and an optional "env"
list of environment variables used to configure that backend.

Query Parameters
Query parameters come after the file URL in standard HTTP format for example:
multi:///path/to/config.json?mode=mirror&onfail=abort
multi:///path/to/config.json?mode=stripe&onfail=continue
multi:///path/to/config.json?onfail=abort&mode=stripe
multi:///path/to/config.json?onfail=abort
Order does not matter, however unrecognized parameters are considered an error.

mode=stripe
This mode (the default) performs round-robin access to the list of backends. In
this mode, all backends must be reliable as a loss of one means a loss of one of
the archive files.

mode=mirror
This mode accesses backends as a RAID1-store, storing every file in every backend
and reading files from the first-successful backend. A loss of any backend should
result in no failure. Note that backends added later will only get new files and
may require a manual sync with one of the other operating ones.

onfail=continue
This setting (the default) continues all write operations in as best-effort. Any
failure results in the next backend tried. Failure is reported only when all
backends fail a given operation with the error result from the last failure.

onfail=abort
This setting considers any backend write failure as a terminating condition and
reports the error. Data reading and listing operations are independent of this and
will try with the next backend on failure.

JSON File Example
[
{
"description": "a comment about the backend"
"url": "abackend://myuser@domain.com/backup",
"env": [
{
"name" : "MYENV",
"value" : "xyz"
},
{
"name" : "FOO",
"value" : "bar"
}
],
"prefixes": ["prefix1_", "prefix2_"]
},
{
"url": "file:///path/to/dir"
}
]

A NOTE ON PAR2 WRAPPER BACKEND

       Par2 Wrapper Backend can be used in combination with all other backends to create recovery
       files. Just add par2+ before a regular scheme (e.g.  par2+ftp://user@host/dir or
       par2+s3+http://bucket_name ). This will create par2 recovery files for each archive and
       upload them all to the wrapped backend.

       Before restoring, archives will be verified. Corrupt archives will be repaired on the fly
       if there are enough recovery blocks available.

       Use --par2-redundancy percent to adjust the size (and redundancy) of recovery files in
       percent.

A NOTE ON PYDRIVE BACKEND

The pydrive backend requires Python PyDrive package to be installed on the system. See
REQUIREMENTS.

There are two ways to use PyDrive: with a regular account or with a "service account".
With a service account, a separate account is created, that is only accessible with Google
APIs and not a web login. With a regular account, you can store backups in your normal
Google Drive.

To use a service account, go to the Google developers console at
https://console.developers.google.com. Create a project, and make sure Drive API is
enabled for the project. Under "APIs and auth", click Create New Client ID, then select
Service Account with P12 key.

Download the .p12 key file of the account and convert it to the .pem format:
openssl pkcs12 -in XXX.p12 -nodes -nocerts > pydriveprivatekey.pem

The content of .pem file should be passed to GOOGLE_DRIVE_ACCOUNT_KEY environment variable
for authentification.

The email address of the account will be used as part of URL. See URL FORMAT above.

The alternative is to use a regular account. To do this, start as above, but when creating
a new Client ID, select "Installed application" of type "Other". Create a file with the
following content, and pass its filename in the GOOGLE_DRIVE_SETTINGS environment
variable:

client_config_backend: settings
client_config:
client_id: <Client ID from developers' console>
client_secret: <Client secret from developers' console>
save_credentials: True
save_credentials_backend: file
save_credentials_file: <filename to cache credentials>
get_refresh_token: True

In this scenario, the username and host parts of the URL play no role; only the path
matters. During the first run, you will be prompted to visit an URL in your browser to
grant access to your drive. Once granted, you will receive a verification code to paste
back into Duplicity. The credentials are then cached in the file references above for
future use.

A NOTE ON GDRIVE BACKEND

GDrive: is a rewritten PyDrive: backend with less dependencies, and a simpler setup - it
uses the JSON keys downloaded directly from Google Cloud Console.

Note Google has 2 drive methods, `Shared(previously Team) Drives` and `My Drive`, both can
be shared but require different addressing

For a Google Shared Drives folder

Share Drive ID specified as a query parameter, driveID, in the backend URL. Example:
gdrive://developer.gserviceaccount.com/target-folder/?driveID=<SHARED DRIVE ID>

For a Google My Drive based shared folder

MyDrive folder ID specified as a query parameter, myDriveFolderID, in the backend URL
Example
export GOOGLE_SERVICE_ACCOUNT_URL=<serviceaccount-name>@<serviceaccount-
name>.iam.gserviceaccount.com
gdrive://${GOOGLE_SERVICE_ACCOUNT_URL}/<target-folder-name-in-
myDriveFolder>?myDriveFolderID=<google-myDrive-folder-id>

There are also two ways to authenticate to use GDrive: with a regular account or with a
"service account". With a service account, a separate account is created, that is only
accessible with Google APIs and not a web login. With a regular account, you can store
backups in your normal Google Drive.

To use a service account, go to the Google developers console at
https://console.developers.google.com. Create a project, and make sure Drive API is
enabled for the project. In the "Credentials" section, click "Create credentials", then
select Service Account with JSON key.

The GOOGLE_SERVICE_JSON_FILE environment variable needs to contain the path to the JSON
file on duplicity invocation.

export GOOGLE_SERVICE_JSON_FILE=<path-to-serviceaccount-credentials.json>

The alternative is to use a regular account. To do this, start as above, but when creating
a new Client ID, select "Create OAuth client ID", with application type of "Desktop app".
Download the client_secret.json file for the new client, and set the
GOOGLE_CLIENT_SECRET_JSON_FILE environment variable to the path to this file, and
GOOGLE_CREDENTIALS_FILE to a path to a file where duplicity will keep the authentication
token - this location must be writable.

During the first run, you will be prompted to visit an URL in your browser to grant access
to your drive. Once granted, you will receive a verification code to paste back into
Duplicity. The credentials are then cached in the file references above for future use.

As a sanity check, GDrive checks the host and username from the URL against the JSON key,
and refuses to proceed if the addresses do not match. Either the email (for the service
accounts) or Client ID (for regular OAuth accounts) must be present in the URL. See URL
FORMAT above.

A NOTE ON RCLONE BACKEND

       Rclone is a powerful command line program to sync files and directories to and from
       various cloud storage providers.

       Once you have configured an rclone remote via

              rclone config

       and successfully set up a remote (e.g. gdrive for Google Drive), assuming you can list
       your remote files with

              rclone ls gdrive:mydocuments

       you can start your backup with

              duplicity /mydocuments rclone://gdrive:/mydocuments

       Please note the slash after the second colon. Some storage provider will work with or
       without slash after colon, but some other will not. Since duplicity will complain about
       malformed URL if a slash is not present, always put it after the colon, and the backend
       will handle it for you.

A NOTE ON SSH BACKENDS

The ssh backends support sftp and scp/ssh transport protocols. This is a known user-
confusing issue as these are fundamentally different. If you plan to access your backend
via one of those please inform yourself about the requirements for a server to support
sftp or scp/ssh access. To make it even more confusing the user can choose between
several ssh backends via a scheme prefix: paramiko+ (default), pexpect+, lftp+... .
paramiko & pexpect support --use-scp, --ssh-askpass and --ssh-options. Only the pexpect
backend allows to define --scp-command and --sftp-command.

SSH paramiko backend (default) is a complete reimplementation of ssh protocols natively in
python. Advantages are speed and maintainability. Minor disadvantage is that extra
packages are needed as listed in REQUIREMENTS. In sftp (default) mode all operations are
done via the according sftp commands. In scp mode ( --use-scp ) though scp access is used
for put/get operations but listing is done via ssh remote shell.

SSH pexpect backend is the legacy ssh backend using the command line ssh binaries via
pexpect. Older versions used scp for get and put operations and sftp for list and delete
operations. The current version uses sftp for all four supported operations, unless the
--use-scp option is used to revert to old behavior.

SSH lftp backend is simply there because lftp can interact with the ssh cmd line binaries.
It is meant as a last resort in case the above options fail for some reason.

Why use sftp instead of scp? The change to sftp was made in order to allow the remote
system to chroot the backup, thus providing better security and because it does not suffer
from shell quoting issues like scp. Scp also does not support any kind of file listing,
so sftp or ssh access will always be needed in addition for this backend mode to work
properly. Sftp does not have these limitations but needs an sftp service running on the
backend server, which is sometimes not an option.

A NOTE ON SSL CERTIFICATE VERIFICATION

       Certificate verification as implemented right now [02.2016] only in the webdav and lftp
       backends. older pythons 2.7.8- and older lftp binaries need a file based database of
       certification authority certificates (cacert file).
       Newer python 2.7.9+ and recent lftp versions however support the system default
       certificates (usually in /etc/ssl/certs) and also giving an alternative ca cert folder via
       --ssl-cacert-path.

       The cacert file has to be a PEM formatted text file as currently provided by the CURL
       project. See

              http://curl.haxx.se/docs/caextract.html

       After creating/retrieving a valid cacert file you should copy it to either

              ~/.duplicity/cacert.pem
              ~/duplicity_cacert.pem
              /etc/duplicity/cacert.pem

       Duplicity searches it there in the same order and will fail if it can't find it.  You can
       however specify the option --ssl-cacert-file <file> to point duplicity to a copy in a
       different location.

       Finally there is the --ssl-no-check-certificate option to disable certificate verification
       alltogether, in case some ssl library is missing or verification is not wanted. Use it
       with care, as even with self signed servers manually providing the private ca certificate
       is definitely the safer option.

A NOTE ON SWIFT (OPENSTACK OBJECT STORAGE) ACCESS

       Swift is the OpenStack Object Storage service.
       The backend requires python-switclient to be installed on the system.  python-
       keystoneclient is also needed to use OpenStack's Keystone Identity service.  See
       REQUIREMENTS.

       It uses following environment variables for authentification: SWIFT_USERNAME (required),
       SWIFT_PASSWORD (required), SWIFT_AUTHURL (required), SWIFT_USERID (required, only for IBM
       Bluemix ObjectStorage), SWIFT_TENANTID (required, only for IBM Bluemix ObjectStorage),
       SWIFT_REGIONNAME (required, only for IBM Bluemix ObjectStorage), SWIFT_TENANTNAME
       (optional, the tenant can be included in the username)

       If the user was previously authenticated, the following environment variables can be used
       instead: SWIFT_PREAUTHURL (required), SWIFT_PREAUTHTOKEN (required)

       If SWIFT_AUTHVERSION is unspecified, it will default to version 1.

A NOTE ON PCA ACCESS

       PCA is a long-term data archival solution by OVH. It runs a slightly modified version of
       Openstack Swift introducing latency in the data retrieval process.  It is a good pick for
       a multi backend configuration where receiving volumes while an other backend is used to
       store manifests and signatures.

       The backend requires python-switclient to be installed on the system.  python-
       keystoneclient is also needed to interact with OpenStack's Keystone Identity service.  See
       REQUIREMENTS.

       It uses following environment variables for authentification: PCA_USERNAME (required),
       PCA_PASSWORD (required), PCA_AUTHURL (required), PCA_USERID (optional), PCA_TENANTID
       (optional, but either the tenant name or tenant id must be supplied) PCA_REGIONNAME
       (optional), PCA_TENANTNAME (optional, but either the tenant name or tenant id must be
       supplied)

       If the user was previously authenticated, the following environment variables can be used
       instead: PCA_PREAUTHURL (required), PCA_PREAUTHTOKEN (required)

       If PCA_AUTHVERSION is unspecified, it will default to version 2.

A NOTE ON MEDIAFIRE BACKEND

       This backend requires mediafire python library to be installed on the system. See
       REQUIREMENTS.

       Use URL escaping for username (and password, if provided via command line):

              mf://duplicity%40example.com@mediafire.com/some_folder

       The destination folder will be created for you if it does not exist.

A NOTE ON SYMMETRIC ENCRYPTION AND SIGNING

       Signing and symmetrically encrypt at the same time with the gpg binary on the command
       line, as used within duplicity, is a specifically challenging issue.  Tests showed that
       the following combinations proved working.

       1. Setup gpg-agent properly. Use the option --use-agent and enter both passphrases
       (symmetric and sign key) in the gpg-agent's dialog.

       2. Use a PASSPHRASE for symmetric encryption of your choice but the signing key has an
       empty passphrase.

       3. The used PASSPHRASE for symmetric encryption and the passphrase of the signing key are
       identical.

KNOWN ISSUES / BUGS

       Hard links currently unsupported (they will be treated as non-linked regular files).

       Bad signatures will be treated as empty instead of logging appropriate error message.

OPERATION AND DATA FORMATS

This section describes duplicity's basic operation and the format of its data files. It
should not be necessary to read this section to use duplicity.

The files used by duplicity to store backup data are tarfiles in GNU tar format. They can
be produced independently by rdiffdir(1). For incremental backups, new files are saved
normally in the tarfile. But when a file changes, instead of storing a complete copy of
the file, only a diff is stored, as generated by rdiff(1). If a file is deleted, a 0
length file is stored in the tar. It is possible to restore a duplicity archive
"manually" by using tar and then cp, rdiff, and rm as necessary. These duplicity archives
have the extension difftar.

Both full and incremental backup sets have the same format. In effect, a full backup set
is an incremental one generated from an empty signature (see below). The files in full
backup sets will start with duplicity-full while the incremental sets start with
duplicity-inc. When restoring, duplicity applies patches in order, so deleting, for
instance, a full backup set may make related incremental backup sets unusable.

In order to determine which files have been deleted, and to calculate diffs for changed
files, duplicity needs to process information about previous sessions. It stores this
information in the form of tarfiles where each entry's data contains the signature (as
produced by rdiff) of the file instead of the file's contents. These signature sets have
the extension sigtar.

Signature files are not required to restore a backup set, but without an up-to-date
signature, duplicity cannot append an incremental backup to an existing archive.

To save bandwidth, duplicity generates full signature sets and incremental signature sets.
A full signature set is generated for each full backup, and an incremental one for each
incremental backup. These start with duplicity-full-signatures and duplicity-new-
signatures respectively. These signatures will be stored both locally and remotely. The
remote signatures will be encrypted if encryption is enabled. The local signatures will
not be encrypted and stored in the archive dir (see --archive-dir ).

REQUIREMENTS

       Duplicity requires a POSIX-like operating system with a python interpreter version 2.6+
       installed.  It is best used under GNU/Linux.

       Some backends also require additional components (probably available as packages for your
       specific platform):

       Amazon Drive backend
              python-requests - http://python-requests.org
              python-requests-oauthlib - https://github.com/requests/requests-oauthlib

       azure backend (Azure Storage Blob Service)
              Microsoft Azure Storage Blobs client library for Python -
              https://pypi.org/project/azure-storage-blob/

       boto backend (S3 Amazon Web Services, Google Cloud Storage)
              boto version 2.0+ - http://github.com/boto/boto

       box backend (box.com)
              boxsdk - https://github.com/box/box-python-sdk

       cfpyrax backend (Rackspace Cloud) and hubic backend (hubic.com)
              Rackspace CloudFiles Pyrax API -
              http://docs.rackspace.com/sdks/guide/content/python.html

       dpbx backend (Dropbox)
              Dropbox Python SDK - https://www.dropbox.com/developers/reference/sdk

       gdocs gdata backend (legacy Google Docs backend)
              Google Data APIs Python Client Library - http://code.google.com/p/gdata-python-
              client/

       gdocs pydrive backend(default)
              see pydrive backend

       gio backend (Gnome VFS API)
              PyGObject - http://live.gnome.org/PyGObject
              D-Bus (dbus)- http://www.freedesktop.org/wiki/Software/dbus

       lftp backend (needed for ftp, ftps, fish [over ssh] - also supports sftp, webdav[s])
              LFTP Client - http://lftp.yar.ru/

       MEGA backend (only works for accounts created prior to November 2018) (mega.nz)
              megatools client - https://github.com/megous/megatools

       MEGA v2 and v3 backend (works for all MEGA accounts) (mega.nz)
              MEGAcmd client - https://mega.nz/cmd

       multi backend
              Multi -- store to more than one backend
              (also see A NOTE ON MULTI BACKEND ) below.

       ncftp backend (ftp, select via ncftp+ftp://)
              NcFTP - http://www.ncftp.com/

       OneDrive backend (Microsoft OneDrive)
              python-requests-oauthlib - https://github.com/requests/requests-oauthlib

       Par2 Wrapper Backend
              par2cmdline - http://parchive.sourceforge.net/

       pydrive backend
              PyDrive -- a wrapper library of google-api-python-client -
              https://pypi.python.org/pypi/PyDrive
              (also see A NOTE ON PYDRIVE BACKEND ) below.

       rclone backend
              rclone - https://rclone.org/

       rsync backend
              rsync client binary - http://rsync.samba.org/

       ssh paramiko backend (default)
              paramiko (SSH2 for python) - http://pypi.python.org/pypi/paramiko (downloads);
              http://github.com/paramiko/paramiko (project page)
              pycrypto (Python Cryptography Toolkit) - http://www.dlitz.net/software/pycrypto/

       ssh pexpect backend
              sftp/scp client binaries OpenSSH - http://www.openssh.com/
              Python pexpect module - http://pexpect.sourceforge.net/pexpect.html

       swift backend (OpenStack Object Storage)
              Python swiftclient module - https://github.com/openstack/python-swiftclient/
              Python keystoneclient module - https://github.com/openstack/python-keystoneclient/

       webdav backend
              certificate authority database file for ssl certificate verification of HTTPS
              connections - http://curl.haxx.se/docs/caextract.html
              (also see A NOTE ON SSL CERTIFICATE VERIFICATION).
              Python kerberos module for kerberos authentication -
              https://github.com/02strich/pykerberos

       MediaFire backend
              MediaFire Python Open SDK - https://pypi.python.org/pypi/mediafire/

AUTHOR

       Original Author - Ben Escoto <bescoto@stanford.edu>

       Current Maintainer - Kenneth Loafman <kenneth@loafman.com>

       Continuous Contributors
              Edgar Soldin, Mike Terry

       Most backends were contributed individually.  Information about their authorship may be
       found in the according file's header.

       Also we'd like to thank everybody posting issues to the mailing list or on launchpad,
       sending in patches or contributing otherwise. Duplicity wouldn't be as stable and useful
       if it weren't for you.

       A special thanks goes to rsync.net, a Cloud Storage provider with explicit support for
       duplicity, for several monetary donations and for providing a special "duplicity friends"
       rate for their offsite backup service.  Email info@rsync.net for details.

NAME

SYNOPSIS

DESCRIPTION

EXAMPLES

ACTIONS

OPTIONS

ENVIRONMENT VARIABLES

URL FORMAT

TIME FORMATS

FILE SELECTION

A NOTE ON AMAZON DRIVE

A NOTE ON AMAZON S3

A NOTE ON AZURE ACCESS

A NOTE ON BOX ACCESS

A NOTE ON CLOUD FILES ACCESS

A NOTE ON DROPBOX ACCESS

A NOTE ON EUROPEAN S3 BUCKETS

A NOTE ON FILENAME PREFIXES

A NOTE ON GOOGLE CLOUD STORAGE

A NOTE ON HUBIC

A NOTE ON IMAP

A NOTE ON MULTI BACKEND

A NOTE ON PAR2 WRAPPER BACKEND

A NOTE ON PYDRIVE BACKEND

A NOTE ON GDRIVE BACKEND

A NOTE ON RCLONE BACKEND

A NOTE ON SSH BACKENDS

A NOTE ON SSL CERTIFICATE VERIFICATION

A NOTE ON SWIFT (OPENSTACK OBJECT STORAGE) ACCESS

A NOTE ON PCA ACCESS

A NOTE ON MEDIAFIRE BACKEND

A NOTE ON SYMMETRIC ENCRYPTION AND SIGNING

KNOWN ISSUES / BUGS

OPERATION AND DATA FORMATS

REQUIREMENTS

AUTHOR

SEE ALSO