[Qemu-devel] Lost network with rtl8139 / qemu-kvm 1.2.0

[Peter Lieven]

Hi all,

I have a strange problem with a few old VMs running with Windows XP (and in 
this case a Win2008 R2 Server) that occasionally loose network connectivity.

The tap device shows increasing drops:
tap36     Link encap:Ethernet  HWaddr b2:84:23:c0:e2:c0
          inet6 addr: fe80::b084:23ff:fec0:e2c0/64 Scope:Link
          UP BROADCAST RUNNING PROMISC MULTICAST  MTU:1500  Metric:1
          RX packets:5816096 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3878744 errors:0 dropped:13775 overruns:0 carrier:0
          collisions:0 txqueuelen:500
          RX bytes:5161769434 (5.1 GB)  TX bytes:380415916 (380.4 MB)

I see this kinf of error only with Windows XP. All other VMs running fine. If I 
live migrate the VM to another
Node connectivity is restored. Rebooting the VM does not help.

The vServer still uses qemu-kvm-1.2.0, but all recent fixes to rtl8139 have 
been backported. The tap device
is also already running with IFF_ONE_QUEUE.

Any ideas?

Thank you,
Peter