[CentOS] routing problem?

Fri Feb 8 15:39:30 UTC 2013
Natxo Asenjo <natxo.asenjo at gmail.com>

hi,

at home I have setup a kvm virtualization lab. I have a layer 3
switch, a host with 3 nics and centos 6.3.

In the layer 3 switch I have setup a couple of vlans: vlan 1
(default), 5 (quarantaine) and 10 (out-of-band-management).

nic0 is configured in the switch as a trunk interface that sees all
vlans. nic2 is an access port on vlan 5 and nic1 is not yet in the
picture ;-)

eth0 is bridged to br0. It also has the host default gateway. I have
also created eth0.5, br0.5, eth0.10 and br0.10 interfaces to add vm's
to vlan 5 and 10 and that works, I can successfully create vms and
assign them to br0.5 or br0.10 and they get ip's from a dchp server in
the correct network and their traffic is correctly routed in the
switch (inter vlan routing works). I can access the vms from my
workstation on on vlan 1.

Now I configure eth2 with an ip address in the range of vlan 5 (in the
switch it is an access port in vlan 5). This is the ifcfg-eth2 file:

DEVICE="eth2"
HWADDR="00:15:17:51:B8:AB"
IPV6INIT="no"
BOOTPROTO=none
MTU="1500"
NM_CONTROLLED="no"
ONBOOT="yes"
IPADDR=192.168.5.10
NETMASK=255.255.255.0
# GATEWAY=192.168.5.254

The GATEWAY parameter is now commented out, but it does not matter.

The interface on the virtualization host comes up all right. But I
cannot access it from my workstation on vlan 1 when accessing it to
vlan 5.

>From the virtualization host I can reach the switch vlan 5 interface
which is its gateway. From the switch I can also ping the interface
eth2.

The routing table on the virt host:

# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
192.168.5.0     0.0.0.0         255.255.255.0   U     0      0        0 eth2
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 br0
169.254.0.0     0.0.0.0         255.255.0.0     U     1003   0        0 eth2
169.254.0.0     0.0.0.0         255.255.0.0     U     1016   0        0 br0
169.254.0.0     0.0.0.0         255.255.0.0     U     1018   0        0 br_v10
169.254.0.0     0.0.0.0         255.255.0.0     U     1020   0        0 br_v5
0.0.0.0         192.168.0.254   0.0.0.0         UG    0      0        0 br0

Do you have any tips on how to reach vlan 5 on the virt host from vlan 1?
--
Groeten,
natxo