.\"
.\" sm-notify(8)
.\"
.\" Copyright (C) 2004 Olaf Kirch <okir@suse.de>
.TH sm-notify 8 "8 Mar 2004
.SH NAME
sm-notify \- Send out NSM reboot notifications
.SH SYNOPSIS
.BI "/sbin/sm-notify [-d] [-q] [-m " time "]
.SH DESCRIPTION
File locking over NFS requires a facility to notify peers in
case of a reboot, so that clients can reclaim locks after
a server crash, and/or
servers can release locks held by the rebooted client.
.PP
This is a two-step process: during normal
operations, a mechanism is required to keep track of which
hosts need to be informed of a reboot. And of course,
notifications need to be sent out during reboot.
The protocol used for this is called NSM, for
.IR "Network Status Monitor" .
.PP
Commonly, these two features are provided by the
.B rpc.statd
daemon.
The SuSE Linux Kernel includes a kernel level implementation
of
.BR statd ", "
which keeps track of the hosts that need notifications, and
accepts reboot notifications.
.PP
This is complemented by the
.B sm-notify
application, which is responsible for sending out the reboot
notifications.
.SS Operation
For each NFS client or server machine to be monitored,
the kernel level
.B statd
creates a file in
.BR /var/lib/nfs/sm ", "
and removes the file if monitoring is no longer required.
.PP
When the machine is rebooted,
.B sm-notify
iterates through these files and notifies the peer
.B statd
server on those machines.
.PP
Each machine has an
.I "NSM state" ,
which is basically an integer counter that is incremented
each time the machine reboots. This counter is stored
in
.BR /var/lib/nfs/state ,
and updated by
.BR sm-notify .
.SH OPTIONS
.TP
.BI -m " failtime
When notifying hosts,
.B sm-notify
will try to contact each host for up to 15 minutes,
and will give up if unable to reach it within this time
frame.
.IP
Using the
.B -m
option, you can override this. A value of 0 tells
sm-notify to retry indefinitely; any other value is
interpreted as the maximum retry time in minutes.
.TP
.BI -v " ipaddr
This option tells
.B sm-notify
to bind to the specified
.IR ipaddr ,
so that all notification packets originate from this address.
This is useful for NFS failover.
.TP
.BI -p " port
instructs
.B sm-notify
to bind to the indicated IP
.IR port
number. If this option is not given, it will try to bind to
a randomly chosen privileged port below 1024.
.TP
.B -q
Be quiet. This suppresses all messages except error
messages while collecting the list of hosts.
.TP
.B -n
Do not update the NSM state. This is for testing only.
.TP
.B -d
Enables debugging.
By default,
.B sm-notify
forks and puts itself in the background after obtaining the
list of hosts from
.BR /var/lib/nfs/sm .
.SH FILES
.BR /var/lib/nfs/state
.br
.BR /var/lib/nfs/sm/*
.br
.BR /var/lib/nfs/sm.bak/*
.SH SEE ALSO
.BR rpc.nfsd(8),
.BR portmap(8)
.SH AUTHORS
.br
Olaf Kirch <okir@suse.de>