5 Replies Latest reply on Apr 17, 2008 6:08 PM by Uke-kun

    "Losing" bridged interface frequently?

    chort Enthusiast

      So far I've found network performance of guest (EL 5.1) to be pretty terrible... I keep seeing what I would call "ARP storms" from the guest, like this:


      09:13:59.082739 arp who-has (ff:ff:ff:ff:ff:ff) tell

      09:13:59.082785 arp reply (0:c:29:c3:27:27) is-at 0:c:29:c3:27:27

      09:14:00.084042 arp who-has (ff:ff:ff:ff:ff:ff) tell

      09:14:00.084089 arp reply (0:c:29:c3:27:27) is-at 0:c:29:c3:27:27

      09:14:01.197812 arp reply is-at 0:c:29:c3:27:27 (0:c:29:c3:27:27)

      09:14:03.625920 arp who-has (ff:ff:ff:ff:ff:ff) tell

      09:14:03.625965 arp reply (0:c:29:c3:27:27) is-at 0:c:29:c3:27:27

      09:14:52.996788 arp who-has (ff:ff:ff:ff:ff:ff) tell

      09:14:52.996832 arp reply (0:c:29:c3:27:27) is-at 0:c:29:c3:27:27

      09:14:53.998528 arp who-has (ff:ff:ff:ff:ff:ff) tell

      09:14:53.998576 arp reply (0:c:29:c3:27:27) is-at 0:c:29:c3:27:27

      09:14:55.107729 arp reply is-at 0:c:29:c3:27:27 (0:c:29:c3:27:27)

      09:14:57.152002 arp who-has (ff:ff:ff:ff:ff:ff) tell

      09:14:57.152047 arp reply (0:c:29:c3:27:27) is-at 0:c:29:c3:27:27

      09:16:04.724552 arp who-has tell

      09:16:04.724600 arp reply is-at 0:d0:b7:2c:57:3e


      ( is the guest)


      All TCP traffic seems to be extremely sluggish, it will go in bursts, and then grind to a halt again.  (removed bit on UDP, on closer inspection that seems to be affected too)


      Anyone else having problems with stability of bridged interfaces?


      PS I have disabled debugging on the guest.

        • 1. Re: "Losing" bridged interface frequently?
          Paul Thomas Master

          What OS are you using as a host?  I tried a performance test on beta1 using the following guests ubuntu, vista, server 2003.  I used sysoft sandra to performance test various guests on each host, however the performance figures were not very consistant between tests, so I wasn't able to draw too many conclusions.  One thing I did notice is that the network performance was much slower when using ubuntu as a host compared to the 2 windows OS's.

          • 2. Re: "Losing" bridged interface frequently?
            chort Enthusiast

            Host is Oracle Enterprise Linux 5.1 with a PAE kernel.  Guest is based on CentOS, either 5.0 or 5.1, can't tell exactly.


            Another note is that the host is running a software RAID5 across 3 physical 10k SCSI drives.  Host disc access doesn't seem too bad, but from the guest it's absolutely abysmal.

            • 3. Re: "Losing" bridged interface frequently?
              yackip1 Enthusiast


              I've been having some odd network problems as well. I'm using Ubuntu 8.04 LTS Beta as my host, my guest is Windows Server 2008. I seem to lose the network every few hours and it requires a reboot. I'm investigating further what's really going on. Any help or thoughts would be greatly appreciated.









              • 4. Re: "Losing" bridged interface frequently?
                Uke-kun Lurker

                I'm using two bridged interfaces on a CentOS VM (one private and one public) and whereas the private interface works fine, I sometimes get no connectivity at all through the public interface. I have tried an Ubuntu guest, and have found no issues at all with networking. I'm running on a Windows Server 2008 host, so I'm guessing the problem lies in CentOS

                • 5. Re: "Losing" bridged interface frequently?
                  yackip1 Enthusiast

                  I found that there were a few issues with only the BRIDGED adapters,

                  including that in W2k8 the os would forget the gateway address (bad) and

                  then also the adapter would stop sending any packets after some time. No

                  idea why yet, but I am looking into it.