Red Hat Bugzilla – Bug 238393
network unreachable with qemu/kvm
Last modified: 2007-11-30 17:12:03 EST
Description of problem:
If I start a qemu guest OS in rawhide it seems the network connection
on eth0 is unreachable. I guess the bridge is not working correctly.
Steps to Reproduce:
1. try to install FC6 via http as a guest OS
Can't connect to http mirror.
Network connection to work like under xenbr.
I configure the qemu guest network to be "Virtual network -> default"
since "Shared physical device" shows no devices.
Can you tell me what kernel version is being used in the guest OS ? The most
likely reason for the broken connectivity is a kernel bug todo with checksumming.
You can verify this theory by doing:
In the host:
ethtool -K virbr0 tx off
And in the guest:
ethtool -K eth0 tx off
With both those disabled, networking should work. The real fix will be done in
the kernel-xen RPM.
(BTW I am running qemu with kernel-2.6.21-1.3116.fc7.x86_64 and kvm.)
Yum upgrading to the latest rawhide today pulled in dnsmasq and networking
is working now. :)
However I am still not able to do a network install of guests for qemu.
BTW is kernel-xen required for networking with qemu?
(I ran "ethtool -K virbr0 tx off" on the host but
couldn't run "ethtool -K eth0 tx off" on a rhel5 qemu guest.)
> However I am still not able to do a network install of guests for qemu.
Actually after rebooting again everything *is* working now. <shrug/>