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pam_motd — Display the motd file

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

DESCRIPTION

pam_motd is a PAM module that can be used to display arbitrary motd (message of
the day) files after a successful login. By default, pam_motd shows files in
the following locations:

/etc/motd
/run/motd
/usr/lib/motd
/etc/motd.d/
/run/motd.d/
/usr/lib/motd.d/

Each message size is limited to 64KB.

If /etc/motd does not exist, then /run/motd is shown. If /run/motd does not
exist, then /usr/lib/motd is shown.

Similar overriding behavior applies to the directories. Files in /etc/motd.d/
override files with the same name in /run/motd.d/ and /usr/lib/motd.d/. Files
in /run/motd.d/ override files with the same name in /usr/lib/motd.d/.

Files the in the directories listed above are displayed in lexicographic order
by name.

To silence a message, a symbolic link with target /dev/null may be placed in /
etc/motd.d with the same filename as the message to be silenced. Example:
Creating a symbolic link as follows silences /usr/lib/motd.d/my_motd.

ln -s /dev/null /etc/motd.d/my_motd

The MOTD_SHOWN=pam environment variable is set after showing the motd files,
even when all of them were silenced using symbolic links.

OPTIONS

motd=/path/filename

    The /path/filename file is displayed as message of the day. Multiple paths
    to try can be specified as a colon-separated list. By default this option
    is set to /etc/motd:/run/motd:/usr/lib/motd.

motd_dir=/path/dirname.d

    The /path/dirname.d directory is scanned and each file contained inside of
    it is displayed. Multiple directories to scan can be specified as a
    colon-separated list. By default this option is set to /etc/motd.d:/run/
    motd.d:/usr/lib/motd.d.

When no options are given, the default behavior applies for both options.
Specifying either option (or both) will disable the default behavior for both
options.

EXAMPLES

The suggested usage for /etc/pam.d/login is:

session  optional  pam_motd.so


To use a motd file from a different location:

session  optional  pam_motd.so motd=/elsewhere/motd


To use a motd file from elsewhere, along with a corresponding .d directory:

session  optional  pam_motd.so motd=/elsewhere/motd motd_dir=/elsewhere/motd.d


AUTHOR

pam_motd was written by Ben Collins <bcollins@debian.org>.

The motd_dir= option was added by Allison Karlitskaya
<allison.karlitskaya@redhat.com>.