KVM: Slow host network; fast guest network


#1

I am in the process of virtualizing (KVM) my server at school (I’m a math teacher). I have a guest Ubuntu 11.04 server running fine. The network performance of the guest is great. But, I am having trouble with the host (Ubuntu 11.04) network performance. It is very slow. Sometimes I can ping the host from the guest and sometimes I cannot. Also, I have “destroyed” and “undefined” the virbr0, as I am using the bridge and not NAT.

I will be administering this server remotely and need independent ssh access to both the host and the vm.

Host network interface:
auto eth0
iface eth0 inet manual

auto br0
iface br0 inet static
address 128.236.28.20
network 128.236.28.0
netmask 255.255.255.0
broadcast 128.236.28.255
gateway 128.236.28.254
bridge_ports eth0
bridge_fd 9
bridge_hello 2
bridge_maxage 12
bridge_stp off

Guest network interface:
auto eth0
iface eth0 inet static
address 128.236.28.22
network 128.236.28.0
netmask 255.255.255.0
broadcast 128.236.28.255
gateway 128.236.28.254

I’ve spent a week trying to find an answer, but to no avail. Could one of you kindly point me in the right direction? If more info is needed, please let me know what you need to see.

Thanks for any help you can give.


#2

I still haven’t found any answers. Any help?