Provided by: ceph-common_17.2.5-0ubuntu2_amd64 
NAME
mount.ceph - mount a Ceph file system
SYNOPSIS
mount.ceph name*@*fsid.*fs_name*=/[subdir] dir [-o options ]
DESCRIPTION
mount.ceph is a helper for mounting the Ceph file system on a Linux host. It serves to
resolve monitor hostname(s) into IP addresses and read authentication keys from disk; the
Linux kernel client component does most of the real work. To mount a Ceph file system use:
mount.ceph name@07fe3187-00d9-42a3-814b-72a4d5e7d5be.fs_name=/ /mnt/mycephfs -o mon_addr=1.2.3.4
Mount helper can fill in the cluster FSID by reading the ceph configuration file. Its
recommended to call the mount helper via mount(8) as per:
mount -t ceph name@.fs_name=/ /mnt/mycephfs -o mon_addr=1.2.3.4
Note that the dot . still needs to be a part of the device string in this case.
The first argument is the device part of the mount command. It includes the RADOS user for
authentication, the file system name and a path within CephFS that will be mounted at the
mount point.
Monitor addresses can be passed using mon_addr mount option. Multiple monitor addresses
can be passed by separating addresses with a slash (/). Only one monitor is needed to
mount successfully; the client will learn about all monitors from any responsive monitor.
However, it is a good idea to specify more than one in case the one happens to be down at
the time of mount. Monitor addresses takes the form ip_address[:port]. If the port is not
specified, the Ceph default of 6789 is assumed.
If monitor addresses are not specified, then mount.ceph will attempt to determine monitor
addresses using local configuration files and/or DNS SRV records. In similar way, if
authentication is enabled on Ceph cluster (which is done using CephX) and options secret
and secretfile are not specified in the command, the mount helper will spawn a child
process that will use the standard Ceph library routines to find a keyring and fetch the
secret from it (including the monitor address and FSID if those not specified).
A sub-directory of the file system can be mounted by specifying the (absolute) path to the
sub-directory right after "=" in the device part of the mount command.
Mount helper application conventions dictate that the first two options are device to be
mounted and the mountpoint for that device. Options must be passed only after these fixed
arguments.
OPTIONS
Basic
conf Path to a ceph.conf file. This is used to initialize the Ceph context for
autodiscovery of monitor addresses and auth secrets. The default is to use the
standard search path for ceph.conf files.
mount_timeout
int (seconds), Default: 60
ms_mode=<legacy|crc|secure|prefer-crc|prefer-secure>
Set the connection mode that the client uses for transport. The available modes
are:
• legacy: use messenger v1 protocol to talk to the cluster
• crc: use messenger v2, without on-the-wire encryption
• secure: use messenger v2, with on-the-wire encryption
• prefer-crc: crc mode, if denied agree to secure mode
• prefer-secure: secure mode, if denied agree to crc mode
mon_addr
Monitor address of the cluster in the form of ip_address[:port]
fsid Cluster FSID. This can be found using ceph fsid command.
secret secret key for use with CephX. This option is insecure because it exposes the
secret on the command line. To avoid this, use the secretfile option.
secretfile
path to file containing the secret key to use with CephX
recover_session=<no|clean>
Set auto reconnect mode in the case where the client is blocklisted. The available
modes are no and clean. The default is no.
• no: never attempt to reconnect when client detects that it has been blocklisted.
Blocklisted clients will not attempt to reconnect and their operations will fail
too.
• clean: client reconnects to the Ceph cluster automatically when it detects that
it has been blocklisted. During reconnect, client drops dirty data/metadata,
invalidates page caches and writable file handles. After reconnect, file locks
become stale because the MDS loses track of them. If an inode contains any stale
file locks, read/write on the inode is not allowed until applications release all
stale file locks.
Advanced
cap_release_safety
int, Default: calculated
caps_wanted_delay_max
int, cap release delay, Default: 60
caps_wanted_delay_min
int, cap release delay, Default: 5
dirstat
funky cat dirname for stats, Default: off
nodirstat
no funky cat dirname for stats
ip my ip
noasyncreaddir
no dcache readdir
nocrc no data crc on writes
noshare
create a new client instance, instead of sharing an existing instance of a client
mounting the same cluster
osdkeepalive
int, Default: 5
osd_idle_ttl
int (seconds), Default: 60
rasize int (bytes), max readahead. Default: 8388608 (8192*1024)
rbytes Report the recursive size of the directory contents for st_size on directories.
Default: off
norbytes
Do not report the recursive size of the directory contents for st_size on
directories.
readdir_max_bytes
int, Default: 524288 (512*1024)
readdir_max_entries
int, Default: 1024
rsize int (bytes), max read size. Default: 16777216 (16*1024*1024)
snapdirname
string, set the name of the hidden snapdir. Default: .snap
write_congestion_kb
int (kb), max writeback in flight. scale with available memory. Default: calculated
from available memory
wsize int (bytes), max write size. Default: 16777216 (16*1024*1024) (writeback uses
smaller of wsize and stripe unit)
wsync Execute all namespace operations synchronously. This ensures that the namespace
operation will only complete after receiving a reply from the MDS. This is the
default.
nowsync
Allow the client to do namespace operations asynchronously. When this option is
enabled, a namespace operation may complete before the MDS replies, if it has
sufficient capabilities to do so.
EXAMPLES
Mount the full file system:
mount -t ceph fs_user@.mycephfs2=/ /mnt/mycephfs
Mount only part of the namespace/file system:
mount.ceph fs_user@.mycephfs2=/some/directory/in/cephfs /mnt/mycephfs
Pass the monitor host's IP address, optionally:
mount.ceph fs_user@.mycephfs2=/ /mnt/mycephfs -o mon_addr=192.168.0.1
Pass the port along with IP address if it's running on a non-standard port:
mount.ceph fs_user@.mycephfs2=/ /mnt/mycephfs -o mon_addr=192.168.0.1:7000
If there are multiple monitors, pass each address separated by a /:
mount.ceph fs_user@.mycephfs2=/ /mnt/mycephfs -o mon_addr=192.168.0.1/192.168.0.2/192.168.0.3
Pass secret key for CephX user optionally:
mount.ceph fs_user@.mycephfs2=/ /mnt/mycephfs -o secret=AQATSKdNGBnwLhAAnNDKnH65FmVKpXZJVasUeQ==
Pass file containing secret key to avoid leaving secret key in shell's command history:
mount.ceph fs_user@.mycephfs2=/ /mnt/mycephfs -o secretfile=/etc/ceph/fs_username.secret
If authentication is disabled on Ceph cluster, omit the credential related option:
mount.ceph fs_user@.mycephfs2=/ /mnt/mycephfs
AVAILABILITY
mount.ceph is part of Ceph, a massively scalable, open-source, distributed storage system.
Please refer to the Ceph documentation at https://docs.ceph.com for more information.
FEATURE AVAILABILITY
The recover_session= option was added to mainline Linux kernels in v5.4. wsync and
nowsync were added in v5.7.
SEE ALSO
ceph-fuse(8), ceph(8)
COPYRIGHT
2010-2023, Inktank Storage, Inc. and contributors. Licensed under Creative Commons
Attribution Share Alike 3.0 (CC-BY-SA-3.0)