Strange Network Failure On C6

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Hi all!

I’m running C6 (up to date) on x86-64. have been running on the same system for over a year.

a couple of times lately access to the outside network has suddenly stopped working for reasons that I didn’t figure out until it happened again yesterday.

I had the time to fool with it, yesterday, so after quite a bit of head-banging I found that it had no default route set up (to make this story less long…).

An appropriate route command “fixed” it and all was well, but… I had rebooted several times, among other drastic actions, such as rebooting the router and cable modem, and none of those things helped. so whatever it was that lost the default route was persistent across boots, while the manual route command to re-add it was NOT persistent across boots.

At some point in fooling with it, I did something–and right now I have no idea what it was–that suddenly caused routes to persist across boots. I know I did not change any of /etc/sysconfig/network*, but I did look at them and saw that ifcfg-eth0 DID contain a line for default route, even though the route command did not reflect it.

So, if anyone has any good guesses on what the heck happened here, I’d like to hear them.

thanks in advance!

3 thoughts on - Strange Network Failure On C6

  • I’ve been running mine for three + years and have had this randomly occur only over the last year or so Not sure what I did to fix it but check these:
    Do you have a GATEWAY2.168.1.1 in the /etc/sysconfig/network file?
    plus in the ifcfg-eth0 file make sure DEFROUTE=yes I actually have a GATEWAY line in this file too plus DNS1= and DNS2and in case it wasn’t obvious NM_CONTROLLED=”no”

    After all this my network comes up about 29 times out of 30, randomly it doesn’t and then I just “sudo service network restart” and all is well. Just fyi, I also find randomly that the gnome login list sometimes sorts alphabetically rather than the default of by UID, no major difficulty but I am sure this kind of randomness is a fairly recent occurrence.

  • actually, GATEWAY is already set in both places. I looked there while the problem was occurring and saw it in both places, and I
    just looked again and yes, its still there. I am, however, allowing NM to manage the network, and I don’t know where it stores its settings.