1LIMITS.CONF(5)                 Linux-PAM Manual                 LIMITS.CONF(5)
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NAME

6       limits.conf - configuration file for the pam_limits module
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DESCRIPTION

9       The syntax of the lines is as follows:
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11       <domain> <type> <item> <value>
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13       The fields listed above should be filled as follows:
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15       <domain>
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17          ·  a username
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19          ·  a groupname, with @group syntax. This should not be confused with
20             netgroups.
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22          ·  the wildcard *, for default entry.
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24          ·  the wildcard %, for maxlogins limit only, can also be used with
25             %group syntax.
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27       <type>
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29          hard
30             for enforcing hard resource limits. These limits are set by the
31             superuser and enforced by the Kernel. The user cannot raise his
32             requirement of system resources above such values.
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34          soft
35             for enforcing soft resource limits. These limits are ones that
36             the user can move up or down within the permitted range by any
37             pre-exisiting hard limits. The values specified with this token
38             can be thought of as default values, for normal system usage.
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40          -  for enforcing both soft and hard resource limits together.
41
42             Note, if you specify a type of '-' but neglect to supply the item
43             and value fields then the module will never enforce any limits on
44             the specified user/group etc. .
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46       <item>
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48          core
49             limits the core file size (KB)
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51          data
52             maximum data size (KB)
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54          fsize
55             maximum filesize (KB)
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57          memlock
58             maximum locked-in-memory address space (KB)
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60          nofile
61             maximum number of open files
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63          rss
64             maximum resident set size (KB)
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66          stack
67             maximum stack size (KB)
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69          cpu
70             maximum CPU time (minutes)
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72          nproc
73             maximum number of processes
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75          as address space limit
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77          maxlogins
78             maximum number of logins for this user
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80          maxsyslogins
81             maximum number of logins on system
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83          priority
84             the priority to run user process with (negative values boost
85             process priority)
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87          locks
88             maximum locked files (Linux 2.4 and higher)
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90          sigpending
91             maximum number of pending signals (Linux 2.6 and higher)
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93          msqqueue
94             maximum memory used by POSIX message queues (bytes) (Linux 2.6
95             and higher)
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97          nice
98             maximum nice priority allowed to raise to (Linux 2.6.12 and
99             higher)
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101          rtprio
102             maximum realtime priority allowed for non-privileged processes
103             (Linux 2.6.12 and higher)
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105       In general, individual limits have priority over group limits, so if
106       you impose no limits for admin group, but one of the members in this
107       group have a limits line, the user will have its limits set according
108       to this line.
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110       Also, please note that all limit settings are set per login. They are
111       not global, nor are they permanent; existing only for the duration of
112       the session.
113
114       In the limits configuration file, the '#' character introduces a
115       comment - after which the rest of the line is ignored.
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117       The pam_limits module does its best to report configuration problems
118       found in its configuration file via syslog(3).
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EXAMPLES

121       These are some example lines which might be specified in
122       /etc/security/limits.conf.
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124          *               soft    core            0
125          *               hard    rss             10000
126          @student        hard    nproc           20
127          @faculty        soft    nproc           20
128          @faculty        hard    nproc           50
129          ftp             hard    nproc           0
130          @student        -       maxlogins       4
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SEE ALSO

134       pam_limits(8), pam.d(5), pam(8)
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AUTHOR

137       pam_limits was initially written by Cristian Gafton <gafton@redhat.com>
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141Linux-PAM Manual                  06/22/2006                    LIMITS.CONF(5)