diff options
| author | NeilBrown <neilb@suse.de> | 2010-02-04 16:31:49 +1100 |
|---|---|---|
| committer | NeilBrown <neilb@suse.de> | 2010-02-04 16:47:28 +1100 |
| commit | 5d4d1b26d3da8b489ed7e2f5a38f7d90b7f4008f (patch) | |
| tree | 86261d4f1521d7953bdbde959fd96bd0fb744d9c /mdmon.8 | |
| parent | 24f6f99b3630b1a89aaa57930c5c9de8a3df9ded (diff) | |
mdmon: allow pid to be stored in different directory.
/var/run probably doesn't persist from early boot.
So if necessary, store in in /lib/init/rw or somewhere else
that does persist.
Signed-off-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'mdmon.8')
| -rw-r--r-- | mdmon.8 | 52 |
1 files changed, 51 insertions, 1 deletions
@@ -5,7 +5,7 @@ mdmon \- monitor MD external metadata arrays .SH SYNOPSIS -.BI mdmon " CONTAINER [NEWROOT]" +.BI mdmon " CONTAINER [NEWROOT | PID]" .SH OVERVIEW The 2.6.27 kernel brings the ability to support external metadata arrays. @@ -148,6 +148,45 @@ will terminate any instances that are running in the current namespace, .IR chroot (2) to NEWROOT, and continue monitoring the container. + +Alternately the new +.I mdmon +can be started after the new root has been installed with +.I pivotroot +by passing +.B / +as the NEWROOT. For +.I mdmon +to be able to find and kill the old +.I mdmon +there must be some part of the filesystem that persists from before +the +.I pivotroot +to afterwards. This can be +.B /var/run/mdadm +or some other directory. The default other directory is +.B /lib/init/rw/mdadm +but this can easily be changed when +.I mdmon +is compiled. +If +.I mdmon +cannot store the pid file in +.B /var/run/mdadm +it will store it in the other directory until +.B /var/run/mdadm +becomes available, or until it is killed. +.TP +[PID] +If the second argument to +.I mdmon +does not start with a slash it is assumed to be the pid of a previous +instance of +.I mdmon +to kill. This is used internally by +.I mdmon +to pass the pid across a chroot/exec and should not be used otherwise. + .PP Note that .I mdmon @@ -159,6 +198,17 @@ RAID arrays. The only times it is run other that by is when the boot scripts need to restart it after mounting the new root filesystem. +.SH EXMAPLES + +.B " mdmon /proc/mdstat /" +.br +Any +.I mdmon +which is currently running is killed and a new instance is started. +This should be run early in the boot sequence after a +.I pivotroot +to the final root filesystem, but before that filesystem is remounted +read-write. .SH SEE ALSO .IR mdadm (8), .IR md (4). |