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diff --git a/upstream/debian-unstable/man5/tmpfs-config.5 b/upstream/debian-unstable/man5/tmpfs-config.5 new file mode 100644 index 00000000..4df348ec --- /dev/null +++ b/upstream/debian-unstable/man5/tmpfs-config.5 @@ -0,0 +1,207 @@ +.TH tmpfs-config 5 "18 Feb 2012" "" "Debian Administrator's Manual" +.SH NAME +tmpfs-config \- variables that configure tmpfs filesystems mounted during boot +.SH DESCRIPTION +The +.I /etc/default/tmpfs +file contains variable settings in POSIX format: +.IP "" .5i +VAR=VAL +.PP +Only one assignment is allowed per line. +Comments (starting with '#') are also allowed. +.PP +This file is for the configuration of tmpfs filesystems mounted in +early boot, before filesystems from /etc/fstab are mounted. This +currently includes the filesystems /run, /run/lock, /run/shm and /tmp. +/run is required to be a tmpfs on systems supporting tmpfs mounts. +/run/lock and /run/shm may be separate tmpfs mounts, useful for +enforcing separate size limits. /tmp is not required to be a tmpfs, +and is not mounted as a tmpfs by default. +.PP + +.IP /run +Previously configured using \fBRAMRUN\fP in /etc/default/rcS, /run is +now always mounted as a ram file system (tmpfs). The size of the +tmpfs can be controlled using TMPFS_SIZE and RUN_SIZE. If desired, +the defaults may also be overridden with an entry in in /etc/fstab, +for example: + +.EX +tmpfs /run tmpfs nodev,nosuid,size=10%,mode=755 0 0 +.EE + +.IP +The contents of /run will always be lost on system reboot, and it it +is no longer explicitly cleaned at boot. Packages can not expect +directories in /run to exist after boot. Packages expecting this are +buggy and need to be fixed. Note that /run was previously /var/run, +and a compatibility symlink or bind mount will be created to allow the +old path to continue to function. + +.IP /run/lock +Previously configured using \fBRAMLOCK\fP in /etc/default/rcS. +Configured using RAMLOCK, TMPFS_SIZE and LOCK_SIZE. If desired, +the defaults may also be overridden with an entry in in /etc/fstab, +for example: + +.EX +tmpfs /run/lock tmpfs nodev,noexec,nosuid,size=52428800,mode=1777 0 0 +.EE + +.IP +Note that irrespective of these settings, /run/lock will be located on +a tmpfs, either one mounted on /run/lock (if RAMLOCK=yes) or one +mounted on /run (if RAMLOCK=no), and as a result the contents of +/var/lock will always be lost on system reboot, and it it is no longer +explicitly cleaned at boot. Packages can not expect directories in +/var/lock to exist after boot. Packages expecting this are buggy and +need to be fixed. Note that /run/lock was previously /var/lock, and a +compatibility symlink or bind mount will be created to allow the old +path to continue to function. + +.IP /run/shm +Previously configured using \fBRAMSHM\fP in /etc/default/rcS. Note +that the setting in /etc/default/rcS, if present, will still be used, +but the setting in /etc/default/tmpfs will take precedence if enabled. +Configured using RAMSHM, TMPFS_SIZE and SHM_SIZE. If desired, the +defaults may also be overridden with an entry in in /etc/fstab, for +example: + +.EX +tmpfs /run/shm tmpfs nosuid,nodev,size=40%,mode=1777 0 0 +.EE + +.IP +Packages can not expect directories in /run/shm to exist after boot. +Note that /run/shm was previously /dev/shm, and a compatibility +symlink or bind mount will be created to allow the old path to +continue to function. If an fstab entry for /dev/shm exists instead +of /run/shm, then /dev/shm will continue to be used; note that this is +only needed for users of newer versions of the Oracle database, which +contain a buggy check for /dev/shm. + +.IP /tmp +Previously configured using \fBRAMTMP\fP in /etc/default/rcS. Note +that the setting in /etc/default/rcS, if present, will still be used, +but the setting in /etc/default/tmpfs will take precedence if enabled. +Configured using RAMTMP, TMPFS_SIZE and TMP_SIZE. If desired, the +defaults may also be overridden with an entry in in /etc/fstab, for +example: + +.EX +tmpfs /tmp tmpfs nodev,nosuid,size=20%,mode=1777 0 0 +.EE + +.IP +Packages can not expect directories in /tmp to exist after boot. + +.PP +\fBNOTE: This file is ignored when systemd is used as init system.\fP + +.SH OPTIONS +The following variables can be set. + +.SS Enabling or disabling tmpfs mounts + +.PP +The following options enable specific mounts (with the exception of +/run) to be enabled or disabled. Note that the addition of an entry +to /etc/fstab for any of the following will enable the mount +unconditionally, overriding the setting here. + +.IP \fBRAMLOCK\fP +Mount /run/lock as a tmpfs (separately from /run). Defaults to +\fByes\fP; set to \fBno\fP to disable (/run/lock will then be part of +the /run tmpfs, if available). + +.IP \fBRAMSHM\fP +Mount /run/shm as a tmpfs (separately from /run). Defaults to +\fByes\fP; set to \fBno\fP to disable (/run/shm will then be part of +the /run tmpfs, if available). + +.IP \fBRAMTMP\fP +Mount /tmp as a tmpfs. Defaults to \fBno\fP; set to \fByes\fP to +enable (/tmp will be part of the root filesystem if disabled). /tmp +may also be configured to be a separate mount in /etc/fstab, which +will override the RAMTMP setting. + +.SS Configuring size limits for tmpfs mounts + +.PP +The following options configure size limits for tmpfs mounts. Note +that the addition of an entry to /etc/fstab will override any of the +limits specified here. +.PP +The following _SIZE variables are the maximum size (in bytes) that +tmpfs filesystems can use. The size will be rounded down to a +multiple of the page size, 4096 bytes. If no size is set, TMPFS_SIZE +will be used as the default. +.PP +More complex mount options may be used by the creation of a +suitable entry in /etc/fstab. For example: + +.EX +tmpfs /run tmpfs size=10% 0 0 +.EE + +is equivalent to + +.EX +RUN_SIZE=10% +.EE + +and will override the RUN_SIZE setting. This will allow additional +options such as nr_blocks and nr_inodes to be used, and also +adjustment of the mode, nodev, nosuid, noexec options should any +change from the defaults be necessary. + +.IP "\fBTMPFS_SIZE\fP" +Maximum size for all tmpfs filesystems if no specific size is +provided. The default is \fB20%VM\fP (20% of virtual memory, +including swap space). If no value is provided here, the kernel +default (50% RAM) will be used. Note that the "%VM" suffix may be +used in this and all the _SIZE settings below, but may not be used in +/etc/fstab (the absolute size is calculated by the init scripts). + +.IP "\fBRUN_SIZE\fP" +Maximum size of /run (was previously /var/run). The default is 10% +core memory; the size required varies widely depending upon the +demands of the software being run; this heuristic scales /run usage on +system size. Samba in particular has been seen to use at least 50MiB +in a large heavily used server. Typical usage is hundreds of KiB, +maximum is tens of MiB. + +.IP "\fBLOCK_SIZE\fP" +Maximum size of /run/lock (was previously /var/lock). Defaults to +5242880 (5 MiB). Typical usage: tens of KiB; maximum hundreds of KiB. +The default of 5 MiB should ensure the limit is never reached. + +.IP "\fBSHM_SIZE\fP" +Maximum size of /run/shm (was previously /dev/shm). No default size; +the size required varies widely depending upon the demands of the +software being run. + +.IP "\fBTMP_SIZE\fP" +Maximum size of /tmp. No default size. + +.SS Emergency overflow /tmp + +.PP +If the amount of free space on the root filesystem falls below a +certain size, a tmpfs will be mounted on /tmp (irrespective of the +RAMTMP setting, which this overrides). This is to permit logins when +there would otherwise be too little free space for this to be possible. + +.IP "\fBTMP_OVERFLOW_LIMIT\fP" +Mount a tmpfs on /tmp if the amount of free space on the root +filesystem is below the specified limit at boot time (default 1024 +KiB). + +.SH AUTHOR +Roger Leigh <rleigh@debian.org> + +.SH SEE ALSO +.BR rcS (5), +.BR tmpfs (5), +.BR mount (8). |