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Strange networking behavior

DISCUSSION Peter Osuchowski 2 participants 2 messages Jan 11, 2008 1 message not in the archive KVM

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Peter Osuchowski

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Hello,

I've noticed this strange networking behavior while running kvm-59 modules and qemu on a custom-compiled 2.6.24-rc5 kernel on x86_64 (2 x Opteron 2210). When I ping a VM from the host it's running on, I get the following result:

talithaA ~ # ping 10.0.1.1
PING 10.0.1.1 (10.0.1.1) 56(84) bytes of data. 64 bytes from 10.0.1.1: icmp_seq=1 ttl=64 time=850 ms 64 bytes from 10.0.1.1: icmp_seq=2 ttl=64 time=389 ms 64 bytes from 10.0.1.1: icmp_seq=3 ttl=64 time=0.353 ms 64 bytes from 10.0.1.1: icmp_seq=4 ttl=64 time=0.366 ms 64 bytes from 10.0.1.1: icmp_seq=5 ttl=64 time=0.361 ms 64 bytes from 10.0.1.1: icmp_seq=6 ttl=64 time=739 ms 64 bytes from 10.0.1.1: icmp_seq=7 ttl=64 time=740 ms 64 bytes from 10.0.1.1: icmp_seq=8 ttl=64 time=741 ms 64 bytes from 10.0.1.1: icmp_seq=9 ttl=64 time=1742 ms 64 bytes from 10.0.1.1: icmp_seq=10 ttl=64 time=731 ms 64 bytes from 10.0.1.1: icmp_seq=11 ttl=64 time=0.373 ms 64 bytes from 10.0.1.1: icmp_seq=12 ttl=64 time=0.380 ms 64 bytes from 10.0.1.1: icmp_seq=13 ttl=64 time=0.383 ms

--- 10.0.1.1 ping statistics ---
14 packets transmitted, 13 received, 7% packet loss, time 13005ms rtt min/avg/max/mdev = 0.353/456.630/1742.288/509.780 ms, pipe 2

On the other hand, when I ping something on the network from the VM, I get:

talithaA-v00 ~ # ping 172.16.1.1
PING 172.16.1.1 (172.16.1.1) 56(84) bytes of data. 64 bytes from 172.16.1.1: icmp_seq=1 ttl=64 time=1011 ms 64 bytes from 172.16.1.1: icmp_seq=2 ttl=64 time=2.81 ms 64 bytes from 172.16.1.1: icmp_seq=3 ttl=64 time=1000 ms 64 bytes from 172.16.1.1: icmp_seq=4 ttl=64 time=1.37 ms 64 bytes from 172.16.1.1: icmp_seq=5 ttl=64 time=1000 ms 64 bytes from 172.16.1.1: icmp_seq=6 ttl=64 time=1.37 ms 64 bytes from 172.16.1.1: icmp_seq=7 ttl=64 time=1000 ms 64 bytes from 172.16.1.1: icmp_seq=8 ttl=64 time=1.37 ms

--- 172.16.1.1 ping statistics ---
9 packets transmitted, 8 received, 11% packet loss, time 8007ms rtt min/avg/max/mdev = 1.375/502.390/1011.591/500.668 ms, pipe 2

The two networks above (10.0.0.0/8 and 172.16.1.0/24) are on seperate Qemu VLANs. The hardware is a Dual Quad-Core Opteron 2210 server and I'm using the default (NE2000) virtual NICs. The host machines have no networking problems.

If anyone could offer any advice, I would be most grateful.

Thanks,
Peter

Signature · 11 lines
Peter Osuchowski
Hosting Operations Engineer
Turtol, LLC.
[email protected]
http://www.turtol.com

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#2 lore raw
Quoted 7 lines · Peter Osuchowski

talithaA ~ # ping 10.0.1.1
PING 10.0.1.1 (10.0.1.1) 56(84) bytes of data. 64 bytes from 10.0.1.1: icmp_seq=1 ttl=64 time=850 ms 64 bytes from 10.0.1.1: icmp_seq=2 ttl=64 time=389 ms 64 bytes from 10.0.1.1: icmp_seq=3 ttl=64 time=0.353 ms 64 bytes from 10.0.1.1: icmp_seq=4 ttl=64 time=0.366 ms 64 bytes from 10.0.1.1: icmp_seq=5 ttl=64 time=0.361 ms

...

Quoted 3 lines

The two networks above (10.0.0.0/8 and 172.16.1.0/24) are on seperate Qemu VLANs. The hardware is a Dual Quad-Core Opteron 2210 server and I'm using the default (NE2000) virtual NICs. The host machines have no networking problems.

The NE2000 code appears to be very broken. Use rtl8139 instead and you should get better results.

-jim

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