'\" t
.\" Title: pam_limits
.\" Author: [see the "AUTHORS" section]
.\" Generator: DocBook XSL Stylesheets v1.79.1
.\" Date: 09/03/2021
.\" Manual: Linux-PAM Manual
.\" Source: Linux-PAM Manual
.\" Language: English
.\"
.TH "PAM_LIMITS" "8" "09/03/2021" "Linux-PAM Manual" "Linux-PAM Manual"
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.SH "NAME"
pam_limits \- PAM module to limit resources
.SH "SYNOPSIS"
.HP \w'\fBpam_limits\&.so\fR\ 'u
\fBpam_limits\&.so\fR [conf=\fI/path/to/limits\&.conf\fR] [debug] [set_all] [utmp_early] [noaudit]
.SH "DESCRIPTION"
.PP
The pam_limits PAM module sets limits on the system resources that can be obtained in a user\-session\&. Users of
\fIuid=0\fR
are affected by this limits, too\&.
.PP
By default limits are taken from the
/etc/security/limits\&.conf
config file\&. Then individual *\&.conf files from the
/etc/security/limits\&.d/
directory are read\&. The files are parsed one after another in the order of "C" locale\&. The effect of the individual files is the same as if all the files were concatenated together in the order of parsing\&. If a config file is explicitly specified with a module option then the files in the above directory are not parsed\&.
.PP
The module must not be called by a multithreaded application\&.
.PP
If Linux PAM is compiled with audit support the module will report when it denies access based on limit of maximum number of concurrent login sessions\&.
.SH "OPTIONS"
.PP
\fBconf=\fR\fB\fI/path/to/limits\&.conf\fR\fR
.RS 4
Indicate an alternative limits\&.conf style configuration file to override the default\&.
.RE
.PP
\fBdebug\fR
.RS 4
Print debug information\&.
.RE
.PP
\fBset_all\fR
.RS 4
Set the limits for which no value is specified in the configuration file to the one from the process with the PID 1\&. Please note that if the init process is systemd these limits will not be the kernel default limits and this option should not be used\&.
.RE
.PP
\fButmp_early\fR
.RS 4
Some broken applications actually allocate a utmp entry for the user before the user is admitted to the system\&. If some of the services you are configuring PAM for do this, you can selectively use this module argument to compensate for this behavior and at the same time maintain system\-wide consistency with a single limits\&.conf file\&.
.RE
.PP
\fBnoaudit\fR
.RS 4
Do not report exceeded maximum logins count to the audit subsystem\&.
.RE
.SH "MODULE TYPES PROVIDED"
.PP
Only the
\fBsession\fR
module type is provided\&.
.SH "RETURN VALUES"
.PP
PAM_ABORT
.RS 4
Cannot get current limits\&.
.RE
.PP
PAM_IGNORE
.RS 4
No limits found for this user\&.
.RE
.PP
PAM_PERM_DENIED
.RS 4
New limits could not be set\&.
.RE
.PP
PAM_SERVICE_ERR
.RS 4
Cannot read config file\&.
.RE
.PP
PAM_SESSION_ERR
.RS 4
Error recovering account name\&.
.RE
.PP
PAM_SUCCESS
.RS 4
Limits were changed\&.
.RE
.PP
PAM_USER_UNKNOWN
.RS 4
The user is not known to the system\&.
.RE
.SH "FILES"
.PP
/etc/security/limits\&.conf
.RS 4
Default configuration file
.RE
.SH "EXAMPLES"
.PP
For the services you need resources limits (login for example) put a the following line in
/etc/pam\&.d/login
as the last line for that service (usually after the pam_unix session line):
.sp
.if n \{\
.RS 4
.\}
.nf
#%PAM\-1\&.0
#
# Resource limits imposed on login sessions via pam_limits
#
session required pam_limits\&.so
.fi
.if n \{\
.RE
.\}
.PP
Replace "login" for each service you are using this module\&.
.SH "SEE ALSO"
.PP
\fBlimits.conf\fR(5),
\fBpam.d\fR(5),
\fBpam\fR(8)\&.
.SH "AUTHORS"
.PP
pam_limits was initially written by Cristian Gafton