Provided by: realmd_0.16.3-1_amd64 
NAME
realm - Manage enrollment in realms
SYNOPSIS
realm discover [realm-name]
realm join [-U user] [realm-name]
realm leave [-U user] [realm-name]
realm list
realm permit [-ax] [-R realm] {user@domain...}
realm deny -a [-R realm]
DESCRIPTION
realm is a command line tool that can be used to manage enrollment in kerberos realms, like Active
Directory domains or IPA domains.
See the various sub commands below. The following global options can be used:
--install=/path
Run in install mode. This makes realmd chroot into the specified directory and place files in
appropriate locations for use during an installer. No packages will be installed or services will be
started when running in this mode.
--unattended
Run in unattended mode without prompting for input.
--verbose, -v
Display verbose diagnostics while doing running commands.
DISCOVER
Discover a realm and its capabilities.
$ realm discover
$ realm discover domain.example.com
After discovering a realm, its name, type and capabilities are displayed.
If no domain is specified, then the domain assigned through DHCP is used as a default.
The following options can be used:
--all
Show all discovered realms (in various configurations).
--client-software=xxx
Only discover realms for which we can use the given client software. Possible values include sssd or
winbind.
--server-software=xxx
Only discover realms which run the given server software. Possible values include active-directory or
ipa.
--membership-software=xxx
Only discover realms for which the given membership software can be used to subsequently perform
enrollment. Possible values include samba or adcli.
JOIN
Configure the local machine for use with a realm.
$ realm join domain.example.com
$ realm join --user=admin --computer-ou=OU=Special domain.example.com
The realm is first discovered, as we would with the discover command. If no domain is specified, then the
domain assigned through DHCP is used as a default.
After a successful join, the computer will be in a state where it is able to resolve remote user and
group names from the realm. For kerberos realms, a computer account and host keytab is created.
Joining arbitrary kerberos realms is not supported. The realm must have a supported mechanism for joining
from a client machine, such as Active Directory or IPA.
If the domain has been preconfigured, and unless --user is explicitly specified, an automatic join is
attempted first.
Note that the --user, --no-password, and --one-time-password options are mutually exclusive. At most one
of them can be specified.
It is generally possible to use kerberos credentials to perform a join operation. Use the kinit command
to acquire credentials prior to starting the join. Do not specify the --user argument, the user will be
selected automatically from the credential cache. The realm respects the KRB5_CCACHE environment
variable, but uses the default kerberos credential cache if it's not present. Not all types of servers
can be joined using kerberos credentials, some (like IPA) insist on prompting for a password.
The following options can be used:
--automatic-id-mapping=no
Do not perform UID/GID mapping for users and groups, but expect these identifiers to be present in
the domain already.
--user=xxx
The user name to be used to authenticate with when joining the machine to the realm. You will be
prompted for a password.
--computer-ou=OU=xxx
The distinguished name of an organizational unit to create the computer account. The exact format of
the distinguished name depends on the client software and membership software. You can usually omit
the root DSE portion of distinguished name. This is an Active Directory specific option.
--no-password
Perform the join automatically without a password.
--one-time-password=xxxx
Perform the join using a one time password specified on the command line. This is not possible with
all types of realms.
--client-software=xxx
Only join realms for which we can use the given client software. Possible values include sssd or
winbind. Not all values are supported for all realms. By default the client software is automatically
selected.
--server-software=xxx
Only join realms for run the given server software. Possible values include active-directory or ipa.
--membership-software=xxx
The software to use when joining to the realm. Possible values include samba or adcli. Not all values
are supported for all realms. By default the membership software is automatically selected.
--user-principal=host/name@REALM
Set the userPrincipalName field of the computer account to this kerberos principal. If you omit the
value for this option, then a principal will be set in the form of host/shortname@REALM
--os-name=xxx
The name of the operation system of the client. When joining an AD domain the value is store in the
matching AD attribute.
--os-version=xxx
The version of the operation system of the client. When joining an AD domain the value is store in
the matching AD attribute.
LEAVE
Deconfigure the local machine for use with a realm.
$ realm leave
$ realm leave domain.example.com
If no realm name is specified, then the first configured realm will be used.
The following options can be used:
--client-software=xxx
Only leave the realm which is using the given client software. Possible values include sssd or
winbind.
--server-software=xxx
Only leave the realm which is using the given server software. Possible values include
active-directory or ipa.
--remove
Remove or disable computer account from the directory while leaving the realm. This will usually
prompt for a pasword.
--user
The user name to be used to authenticate with when leaving the realm. You will be prompted for a
password. Implies --remove.
LIST
List all the discovered and configured realms.
$ realm list
By default, realms that have been discovered, but not configured (using the join command), are not
displayed. Also, by default, the list of realm details displayed is verbose. The options below can be
used to change this default behavior
The following options can be used:
--all
Show all discovered realms (whether or not they have been configured).
--name-only
Display only realm names (as opposed to verbose output).
PERMIT
Permit local login by users of the realm.
$ realm permit --all
$ realm permit user@example.com
$ realm permit DOMAIN\\User2
$ realm permit --withdraw user@example.com
The current login policy and format of the user names can be seen by using the realm list command.
The following options can be used:
--all, -a
Permit logins using realm accounts on the local machine according to the realm policy.This usually
defaults to allowing any realm user to log in.
--groups, -g
Treat the specified names as groups rather than user login names. Permit login by users in the
specified groups.
--realm, -R
Specify the of the realm to change login policy for.
--withdraw, -x
Remove a login from the list of realm accounts permitted to log into the machine.
DENY
Deny local login by realm accounts.
$ realm deny --all
This command prevents realm accounts from logging into the local machine. Use realm permit to restrict
logins to specific accounts.
The following options can be used:
--all, -a
This option should be specified
--realm, -R
Specify the name of the realm to deny users login to.
AUTHOR
Stef Walter <stef@thewalter.net> Maintainer