At 10:16 PM 5/27/02 +0200, Kiril wrote: >My ISP sometimes has short network outages (2-3 minutes). After such an >outage, I have to manually restart networking to get my router back online. > >Is there a simple and reliable way to test the status of a connection? a >script that can runs constantly, supervised by daemontools, and restarts >networking after some waiting period is what i am looking for
Assuming we are talking about a connection handled by an external device (e.g., a cable or DSL "modem" that connects to the LEAF router via an eth* interface, and NOT a ppp connection over a dialup modem), the only real way to see if the remote network is working is to try to make it do something. A ping is the lightest weight "something" there is. A one-per-minute ping to the ISP's default gateway really isn't much of a burden on it ... and since they are the ones causing the periodic interruptions, surely they can't with any sincerity claim your behavior to be "unfriendly". And its' a good host to pick for another reason too -- if it does go offline, that act cuts off your access to the Internet, so you won't be detecting a false failure. >ping somehow does not work best. the host that i am trying to ping could go >offline, dns could fail and constantly pinging some other host seems not >particularly friendly to me. > >i tried also ip addr show | grep eth0 | grep inet, but this also did not >really work out, because routing could fail. In any case, a failure at the ISP end won't cause your routing table to be rewritten, unless you are using a system that gets a new DHCP lease every few minutes. >one could always test all conditions, but before i do this, i would like to >ask the list if there is a more elegant way. Really, it depends on what the local symptoms of these brief connectivity failures are. I've been making some assumptions about that in my response, but a better approach is for you to characterize the failures a bit more exactly. -- -----------------------------------------------"Never tell me the odds!"-------------- Ray Olszewski -- Han Solo Palo Alto, California, USA [EMAIL PROTECTED] ------------------------------------------------------------------------------------------- _______________________________________________________________ Don't miss the 2002 Sprint PCS Application Developer's Conference August 25-28 in Las Vegas -- http://devcon.sprintpcs.com/adp/index.cfm ------------------------------------------------------------------------ leaf-user mailing list: [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/leaf-user SR FAQ: http://leaf-project.org/pub/doc/docmanager/docid_1891.html