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New Member


I have two 3550's (24 port each) and 2811 router. I have two gropus of users 16 and 32. My router is connected to the rmote site and it has two fast ethernet ports available.

Now i need to configure this in such a way that even if one switch failes at least somes users of both the groups should communacate. So waht I did is

I divided both the groups on the two switches like (8 and 16) on each. Connected the two swithes using a trunk. NOw I want to know how to connect my router.

Hall of Fame Super Bronze

Re: Redudancy

You should trunk each FastEthernet on the 2811 and connect each link to a different switch.

This should provide the required redundancy.

New Member

Re: Redudancy


Thanx for your response. BUt i ahve only one dhcp server which is in my vlan 2. One more question is should i create SVI's for both the vlans on each fastethernet interface.

Hall of Fame Super Bronze

Re: Redudancy

You can setup the ip helper-address in the 2811. That should address your DHCP issue.

I recommend letting the 2811 doing the routing between VLANs thus no need for SVIs on the 3550s.

New Member

Re: Redudancy

I have additional comment about configuring multiple VLANs on your 2811...

I don't believe you can configure VLAN interfaces on the 2811, out of the box. What you can do, however, is configure each built-in FE port on the router to use 802.1Q encapsulation. Here's what you do:

interface fa0/0

description Trunk To Switch no. 1, VLANs 10 & 20

no ip address

interface fa0/0.10

description Connected to VLAN 10

encapsulation dot1q 10

ip address

no shutdown

interface fa0/0.20

description Connected to VLAN 20

encapsulation dot1q 20

ip address

no shutdown

Do the same thing for Fa0/1.