.\"
.\" -*- nroff -*-
.\"
.\"  Copyright (c) Thomas Andrews
.\"
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.TH LINKMON 1 "October 2009" Unix "User Manuals"
.\" Please adjust this date whenever revising the manpage.
.\"
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.SH NAME
linkmon \- Link Monitor
.SH SYNOPSIS
.B linkmon
.RI \-h\ HOST
.RI \-c\ COMMAND
.OP \-i\ INTERVAL
.OP \-n\ FAILURES
.OP \-t\ TIMEOUT
.OP \-d\ DEBUGLEVEL
.OP \-l\ SYSLOG_FACILITY
.SH DESCRIPTION
This program sends ICMP ECHO packets to the address of 
your choice and then listens for ICMP REPLY packets.
If there's no response after the specified period it will retry repeatedly
until the specified count is reached, after which it will execute
the command specified. You can specify the period between pings
and also the number of failed attempts to make before running the command.
The syslog 'facility' can be set to a numerical value.

It doesn't daemonise - it is meant to be run from inittab.
It has to be run with UID 0 (ie root privileges)

    \fIHOST\fP and COMMAND must be provided
    \fICOMMAND\fP must be put into quotes if it has more than one argument
    \fIINTERVAL\fP, \fIFAILURES\fP, \fITIMEOUT\fP, \fIDEBUGLEVEL\fP, and \fISYSLOG_FACILITY\fP are optional

    \fIINTERVAL\fP defaults to 5 seconds between pings
    \fITIMEOUT\fP defaults to 5 seconds (awaiting response)
    \fIFAILURES\fP defaults to 5 attempts
    \fIDEBUGLEVEL\fP defaults to level 2
    \fISYSLOG_FACILITY\fP defaults to 24

.SH OPTIONS
A summary of options is included below.
.TP
.B \-d
Debug verbosity. The following levels can be specified:
.P
.ds a \t0 off
.ds b \t1 panic
.ds c \t2 error
.ds d \t3 warning
.ds e \t4 info
.ds f \t5 verbose
.ta 1i 2i
\*[a]
.br
\*[b]
.br
\*[c]
.br
\*[d]
.br
\*[e]
.br
\*[f]
.br
.TP
.B \-h
IP address of hostname to send ICMP echo requests to.
.TP
.B \-c
Command to run once after n consecutive failed attempts.
.TP
.B \-i
Interval (seconds) between attempts.
.TP
.B \-n
Number of consecutive failed attempts before running command.
.TP
.B \-t
Timeout per request.
.TP
.B \-l
Syslog facility level (numeric)
.SH EXAMPLES
.sp
linkmon -h 169.254.1.1 -c 'killall pppd'
.sp
linkmon -h 169.254.1.1 -c 'killall pppd' -n10 -t5 -i5 -d3
.SH SEE ALSO
fping(1)
.SH AUTHOR
Written by Thomas Andrews