Script to check connection (and restart network if down)
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Routing, network cards, OSI, etc. Anything is fair game.
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the network will get restarted even if it's up. Removing the "!" seems to have the desired effect, but it just looks incorrect. What is going on here? Possibly our versions of the "ping" program have different implementations?
Last edited by VibeOfOurTribe; 12-09-2004 at 12:57 PM.
Yes, it seems there is something slightly wrong with the script.
My network connection usually dies about once every three weeks. I've been running this script nonstop for about five days, and it has restarted my network at least 15 times. So it is giving some false positives for the network being down.
Hande: If it's not too late, here's something I just wrote for my own use. It should be simple to modify such that it tests packet loss for multiple IP's and acts based on the average. Run using the crontab examples posted previously.
# Script to monitor and restart wireless access point when needed
maxPloss=10 #Maximum percent packet loss before a restart
# Add any commands need to get network back up and running
#only needed if your running a wireless ap
# First make sure we can resolve google, otherwise 'ping -w' would hang
if ! $(host -W5 www.google.com > /dev/null 2>&1); then
#Make a note in syslog
logger "wap_check: Network connection is down, restarting network ..."
# Initialize to a value that would force a restart
# (just in case ping gives an error and ploss doesn't get set)
# now ping google for 10 seconds and count packet loss
ploss=$(ping -q -w10 www.google.com | grep -o "[0-9]*%" | tr -d %) > /dev/null 2>&1
if [ "$ploss" -gt "$maxPloss" ]; then
logger "Packet loss ($ploss%) exceeded $maxPloss, restarting network ..."
the simplest way to do what you want would be to install
wicd and set it to aoutmaticly reconnect BUT you need to go back to the out of the box net work settings for the network
interface you use to connect to the inter net
it will work for eather net connections
I use it for wifi it's so fast at reconneccting that videos
on youtube don't even buffer befor the connection is back up