Hello,

On a RHEL 5 server, we do have 4 NICs. Two vlan's (802.1q tagging) have to be configured on eth3, but the physical interface eth3 does not have an own IP!

Here's what I did so far:
- creating ifcfg-eth3.2548 at /etc/sysconfig/network-scripts:

DEVICE=eth3.2548
BOOTPROTO=none
ONBOOT=yes
TYPE=Ethernet
NETMASK=255.255.255.128
IPADDR=10.140.27.125
VLAN=yes

- creating ifcfg-eth3.2549 at /etc/sysconfig/network-scripts:

DEVICE=eth3.2549
BOOTPROTO=none
ONBOOT=yes
TYPE=Ethernet
NETMASK=255.255.255.128
IPADDR=10.140.27.253
VLAN=yes

- Note: There is no file ifcfg-eth3 at /etc/sysconfig/network-scripts !
- The other interfaces eth0, eth1 and eth2 are configured "normally"

But somehow this configuration leads to strange network behaviour. For example, I can't connect to an application from LAN via eth2 anymore. If I rename the ifcfg-eth3.xxxx files and restart the server, connection to the application from LAN works fine!

Is it possible to set vlan's on a physical interface that has no IP? Or did I forget something else?

Many thanks,
Peter

Is it possible to post here output of command: ifconfig -a, to see configuration of all available interfaces.

Thanks.

Hi,

Sorry, the error occured at a totally different place, nothing to do with VLANs...

I can confirm now that it is easily possible to define multiple VLANs at one physical interface that has no own IP.

Thanks & regards,
Peter