VLAN trunking and fragmentation

[Andrew Thompson]

On Wed, Mar 12, 2008 at 12:38:06PM -0700, Sean Chittenden wrote:
>> interface ethernet 1/g1
>> switchport mode trunk
>> switchport trunk allowed vlan add 10
>> exit
>
> I think this is an issue with default VLAN membership.  I have this config 
> running on *hundreds* of servers without issue.  Since Dell should be a 
> cisco rip-off, on your switchport config, throw in (haven't tested this, on 
> dell's CLI):
>
>  switchport trunk encapsulation dot1q
>
> then change your ifconfig foo to:
>
> cloned_interfaces="vlan10 vlan11"
> ifconfig_re0="media 100baseTX mediaopt full-duplex"
> ifconfig_vlan10="vlan 10 vlandev re0"
> ifconfig_vlan10_alias0="inet 192.168.60.1 netmask 255.255.255.0"
> ifconfig_vlan11="vlan 11 valndev re0"
> ifconfig_vlan11_alias0="inet 192.168.100.1 netmask 255.255.255.0"
>
> FWIW, I think you'll find fewer gray hairs if you stick to the convention 
> of using a vlan device that has the same VLAN tag.  You may be able to have 
> a default VLAN, but I consider it poor practice to rely on default VLAN 
> membership.

Even nicer is using <interface>.<number> autoconfig, the following is
equivalent to above:

cloned_interfaces="re0.10 re0.11"
ifconfig_re0="media 100baseTX mediaopt full-duplex"
ifconfig_re0.10="inet 192.168.60.1 netmask 255.255.255.0"
ifconfig_re0.11="inet 192.168.100.1 netmask 255.255.255.0"



Andrew