vlan on Cisco 3845

[anitagaur]

Is configuring vlans supported on cisco 3845 router?

[Giuseppe Larosa]

Hello Anita,

it makes sense to define Vlans only if you have some type of etherswitch module installed in the C3845.

In that case you can and actually you need to define L2 Vlans to use the ports of the module. You can also define L3 SVI vlans interfaces.

If you have only normal routed ports you can define Vlan based subinterfaces as

int f0/0

no ip address

int f0/0.100

enc dot1q 100

ip address 10.10.100.1 255.255.255.0

int fas0/0.110

enc dot1q 220

ip address 10.10.110.1 255.255.255.0

on the other side of f0/0 there is usually a L2 trunk on an external lan switch

Hope to help

Giuseppe

[anitagaur]

Hi Giuseppe,

I have a NME-X-23ES-1G network service module installed on the 3845 but I do not see interface vlan command option in the router. IOS is 12.4(18b)

[Giuseppe Larosa]

Hello Anita,

your module is so smart that it has its own IOS image.

you need to telnet to the module and to configure it.

see

Cisco EtherSwitch service modules do not have a physical console interface, but are accessible for software configuration and other operational procedures through console sessions between the Cisco EtherSwitch service module and the host router.

http://www.cisco.com/en/US/docs/routers/access/interfaces/nm/hardware/installation/guide/conneths.html#wp1124297

So in your case the switch module is hosted by the router but has its own IOS image and configuration.

I've used only the dumb etherswitch modules that are configured from the router.

Hope to help

Giuseppe

[turnera]

Yes they are, I am using NME-X-23ES-1G modules in our network. Get rid of (upgrade) the IPBASE IOS and you can accomplish much more with these modules.