|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: [Xen-users] a lot of packet loss
I commented out the resolv.conf, but nothing changed. I also tried the tcpdump issue. I experienced this: root@test5:~# ping 172.27.68.28 PING 172.27.68.28 (172.27.68.28) 56(84) bytes of data. 64 bytes from 172.27.68.28: icmp_seq=10 ttl=64 time=0.189 ms 64 bytes from 172.27.68.28: icmp_seq=11 ttl=64 time=0.218 ms --- 172.27.68.28 ping statistics --- 16 packets transmitted, 2 received, 87% packet loss, time 15004ms rtt min/avg/max/mdev = 0.189/0.203/0.218/0.020 ms On the host: root@test6:~# cat dom0tcpdump > dom0tcpdump root@test6:~# cat dom0tcpdump | grep ICMP 01:03:19.108715 IP 172.27.68.114 > 172.27.68.28: ICMP echo request, id 7461, seq 10, length 64 01:03:19.108754 IP 172.27.68.28 > 172.27.68.114: ICMP echo reply, id 7461, seq 10, length 64 01:03:20.108733 IP 172.27.68.114 > 172.27.68.28: ICMP echo request, id 7461, seq 11, length 64 01:03:20.108770 IP 172.27.68.28 > 172.27.68.114: ICMP echo reply, id 7461, seq 11, length 64 On the guest: root@test-vm2:~# tcpdump > domutcp root@test-vm2:~# cat domutcp | grep ICMP 01:03:19.142677 IP 172.27.68.114 > 172.27.68.28: ICMP echo request, id 7461, seq 10, length 64 01:03:19.142677 IP 172.27.68.28 > 172.27.68.114: ICMP echo reply, id 7461, seq 10, length 64 01:03:20.108578 IP 172.27.68.114 > 172.27.68.28: ICMP echo request, id 7461, seq 11, length 64 01:03:20.108578 IP 172.27.68.28 > 172.27.68.114: ICMP echo reply, id 7461, seq 11, length 64 It is very interesting, because it seems that the ICMP packets even dont reach the host OS, but If I ping the host OS, each ICMP echo request got an ECHO reply. I read about this network problem in another forums, and someone had the same problem. He tought it is scheduling problem. On Sat, May 2, 2009 at 12:49 AM, Bhasker C V <bhasker@xxxxxxxxxxxxx> wrote: > On Fri, 1 May 2009, Attila Szamos wrote: > >> I've fix-ed the timesyncronization problem. But I don't know where to >> start with the network problem. >> If I ping the VM a lot of packet didn't get an echo reply. >> >> root@test6:~# ping perftest-vm2 >> PING test-vm2 (172.27.68.28) 56(84) bytes of data. >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=1 ttl=64 time=0.346 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=2 ttl=64 time=0.048 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=3 ttl=64 time=0.039 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=4 ttl=64 time=0.041 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=6 ttl=64 time=0.032 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=7 ttl=64 time=0.044 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=8 ttl=64 time=0.038 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=43 ttl=64 time=8.05 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=56 ttl=64 time=0.042 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=57 ttl=64 time=0.036 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=58 ttl=64 time=0.041 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=59 ttl=64 time=0.038 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=60 ttl=64 time=0.041 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=61 ttl=64 time=0.038 ms >> 64 bytes from test-vm2 (172.27.68.28): icmp_seq=62 ttl=64 time=0.033 ms >> >> --- test-vm2 ping statistics --- >> 64 packets transmitted, 15 received, 76% packet loss, time 63064ms >> rtt min/avg/max/mdev = 0.032/0.594/8.056/1.995 ms > > Does the ping directly to IP address too gives the same issue ? > sometimes DNS is a pain... > also on the domU side, try commenting out the complete resolv.conf > just to take DNS out of the way and try direct IP ping. > > you can also on the domU side run a tcpdump and check why the particular > icmp sequence number is missing. you can see the replies from domU and > if the reply does not come to the dom0, then there could be a problem with > xen. > else > ... > >> >> I've tried to switch the networking to 'route' from 'bridge', but it >> didn't help. Any suggestions? >> >> _______________________________________________ >> Xen-users mailing list >> Xen-users@xxxxxxxxxxxxxxxxxxx >> http://lists.xensource.com/xen-users >> > > Bhasker C V > Registered linux user #306349 > > > _______________________________________________ Xen-users mailing list Xen-users@xxxxxxxxxxxxxxxxxxx http://lists.xensource.com/xen-users
|
 |
Lists.xenproject.org is hosted with RackSpace, monitoring our |