LinuxQuestions.org - KVM guest with 2 network interfaces in diferrent VLANs

Hi all,

I would like to configure a guest VM which will have two network interfaces in different VLANs (106,711).

the host configuration looks as follows:
/etc/sysconfig/network-scripts/ifcfg-eth0 (connected to a trunk port)

Code:

DEVICE=eth0

BOOTPROTO=none

HWADDR=00:22:19:D4:25:A8

IPV6INIT=no

IPV6_AUTOCONF=no

ONBOOT=yes

TYPE=Ethernet

/etc/sysconfig/network-scripts/ifcfg-eth0.106

Code:

DEVICE=eth0.106

BOOTPROTO=none

HWADDR=00:22:19:D4:25:A8

ONBOOT=yes

TYPE=Ethernet

VLAN=yes

/etc/sysconfig/network-scripts/ifcfg-eth0.711

Code:

DEVICE=eth0.711

BOOTPROTO=none

HWADDR=00:22:19:D4:25:A8

ONBOOT=yes

TYPE=Ethernet

VLAN=yes

Then I added two bridges for both VLANs

Code:

brctl addbr br0

brctl addif br0 eth0.711

ifconfig br0 10.56.2.2 netmask 255.255.255.240 up

brctl addbr br1

brctl addif br1 eth0.106

ifconfig br1 10.238.22.8 netmask 255.255.255.0

and created two tap interfaces and added them to the corresponding bridges.

Code:

tunctl -b -u root

ifconfig tap0 up

brctl addif br0 tap0

tunctl -b -u root

ifconfig tap1 up

brctl addif br1 tap1

The brctl show command output looks fine:

Code:

brctl show

bridge name        bridge id                STP enabled        interfaces

br0                8000.002219d425a8        no                tap0

                                                        eth0.711

br1                8000.002219d425a8        no                tap1

                                                        eth0.106

The virtual machine is started

Code:

/usr/libexec/qemu-kvm -hda /data/disk.raw  -smp 2 -m 2G -net nic,macaddr=52:54:00:12:34:55 -net tap,ifname=tap0,script=no  -net nic,macaddr=52:54:00:12:34:75 -net tap,ifname=tap1,script=no

The guest has 2 interfaces (eth0=tap0,eth1=tap1)
The problem I have is that even though the tap1 interface is bridged to the VLAN 106 the eth1 interface in the guest still gets an IP address from the VLAN 711. Is my setup correct or am I missing anything?

I use CentOS 5.6 as the host system.

Thanks for your help

Tomas