1PAM_MOTD(8) Linux-PAM Manual PAM_MOTD(8)
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6 pam_motd - Display the motd file
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9 pam_motd.so [motd=/path/filename] [motd_dir=/path/dirname.d]
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12 pam_motd is a PAM module that can be used to display arbitrary motd
13 (message of the day) files after a successful login. By default,
14 pam_motd shows files in the following locations:
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16 /etc/motd
17 /run/motd
18 /usr/lib/motd
19 /etc/motd.d/
20 /run/motd.d/
21 /usr/lib/motd.d/
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23 Each message size is limited to 64KB.
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25 If /etc/motd does not exist, then /run/motd is shown. If /run/motd does
26 not exist, then /usr/lib/motd is shown.
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28 Similar overriding behavior applies to the directories. Files in
29 /etc/motd.d/ override files with the same name in /run/motd.d/ and
30 /usr/lib/motd.d/. Files in /run/motd.d/ override files with the same
31 name in /usr/lib/motd.d/.
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33 Files in the directories listed above are displayed in lexicographic
34 order by name. Moreover, the files are filtered by reading them with
35 the credentials of the target user authenticating on the system.
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37 To silence a message, a symbolic link with target /dev/null may be
38 placed in /etc/motd.d with the same filename as the message to be
39 silenced. Example: Creating a symbolic link as follows silences
40 /usr/lib/motd.d/my_motd.
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42 ln -s /dev/null /etc/motd.d/my_motd
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44 The MOTD_SHOWN=pam environment variable is set after showing the motd
45 files, even when all of them were silenced using symbolic links.
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48 motd=/path/filename
49 The /path/filename file is displayed as message of the day.
50 Multiple paths to try can be specified as a colon-separated list.
51 By default this option is set to /etc/motd:/run/motd:/usr/lib/motd.
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53 motd_dir=/path/dirname.d
54 The /path/dirname.d directory is scanned and each file contained
55 inside of it is displayed. Multiple directories to scan can be
56 specified as a colon-separated list. By default this option is set
57 to /etc/motd.d:/run/motd.d:/usr/lib/motd.d.
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59 When no options are given, the default behavior applies for both
60 options. Specifying either option (or both) will disable the default
61 behavior for both options.
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64 Only the session module type is provided.
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67 PAM_ABORT
68 Not all relevant data or options could be obtained.
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70 PAM_BUF_ERR
71 Memory buffer error.
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73 PAM_IGNORE
74 This is the default return value of this module.
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77 The suggested usage for /etc/pam.d/login is:
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79 session optional pam_motd.so
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82 To use a motd file from a different location:
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84 session optional pam_motd.so motd=/elsewhere/motd
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87 To use a motd file from elsewhere, along with a corresponding .d
88 directory:
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90 session optional pam_motd.so motd=/elsewhere/motd motd_dir=/elsewhere/motd.d
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95 motd(5), pam.conf(5), pam.d(5), pam(8)
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98 pam_motd was written by Ben Collins <bcollins@debian.org>.
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100 The motd_dir= option was added by Allison Karlitskaya
101 <allison.karlitskaya@redhat.com>.
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105Linux-PAM Manual 09/03/2021 PAM_MOTD(8)