vpnc auto-reconnect script

#!/bin/ksh

# This script was developed on OpenBSD with ksh as the primary shell.

# set INT_SERVER to a list of 5 ping-able machines behind your vpn gateway
# ip addresses can be repeated if you have less than five machines.
set -A INT_SERVER 192.168.1.16 192.168.1.201 192.168.1.205 192.168.1.230 192.168.1.129

# this script expects vpnc to be properly configured beforehand with a working profile.
# this script only handles detecting a dropped tunnel and re-establishing the tunnel.
VPNC=/usr/local/sbin/vpnc
DISC=/usr/local/sbin/vpnc-disconnect
TUN=tun0

debug=0 # automatically tuned if vpnc fails...

while [ 1 -eq 1 ]; do # main loop

        echo "Connecting to vpn gateway at `date`...";
        [ $debug -gt 3 ] && debug=3
        $VPNC --debug $debug
        [ $? -gt 0 ] && { echo "connection failed!"; debug=`expr $debug + 1`; $DISC; ifconfig $TUN destroy; sleep 1; continue; } || echo "Connected!"

        sleep 1; # let the VPN "settle" before testing connectivity

        checks=0
        while [ $checks -lt 5 ]; do

                server=${INT_SERVER[$checks]}
                checks=`expr $checks + 1`
                success=0

                while ping -c 1 -w $checks -i $checks $server >/dev/null 2>&1; do

                        sleep $checks
                        success=`expr $success + 1`
                        [ $success -gt 60 -a $checks -gt 4 ] && { checks=0; echo "Resetting failure count."; }

                done

                echo "Failed check #$checks - $server"
        done

        echo "Tunnel dropped at `date`...resetting!"
        $DISC 2>/dev/null;
        ifconfig $TUN destroy;
        sleep 1;
done