Multilink Interface using e/0 and e/1

[snootalope]

Is it possible/supported to create a multilink interface that can utilize both Ethernet ports on say a 2811 ISR?

Here's my dilemma, I've got design at a remote office where everything in that office has redundant paths to two different switches. So, in the event one switch dies, they can always use the other switch to get out. If I do this, I'd have to have two paths to the gateway. So, here's my thinking; I run a cat from e/0 and e/1 - one port to one switch and the other port to the other switch. Set the Multilink interface with my sub-interface IP's and add both e/0 and e/1 to the Multilink group.

This doable?

 

[burtsbees]

Why not a floating static route?

Burt

 

[Minue]

Hello
The multilink will need PPP encapsulation which isn't compatable with Ethernet.Are the switches layer 3 or 2 ? If they are layer 2 the closes you can get to achieving what you want to do,is stacking the switches and trying etherchannel.

Regards

 

[NetworksMD]

Is the office a flat network that you are trying to set redundancy into layer 2? The other question would be what if your router fails? I have designed a remote office with 2 2811 routers with layer 3 switch modules and set up one SVI for each vlan on each switch, then set HSRP where every other vlan used the alternate switch as the primary, which worked quite well. You could do the same by setting up two interfaces on two different routers and setting up HSRP for one flat network.

 

[snootalope]

Good point there networks, what if the router fails? Fortunately, the 2811 we've been using for quite some time now has been very solid, no issues at all. However it would be nice to eliminate the single point of failure here.. might utilize a spare 1751 we've got sitting around here.

Burt, can you elaborate a bit on these floating static routes? I'm not familiar with them. Will that allow me to use both interfaces on the router? I have to keep two different sub-interfaces setup as well. Got a data subnet and a voice subnet that'll both use this device as their set gateway.

For example, here's what I got now, just the one interface active. I'd like to make a multilink and group the two e's together, everything data uses the Data interface as their gateway and everything voice uses the Voice interface as its gateway:

!
interface FastEthernet0/0
no ip address
no ip redirects
no ip unreachables
no ip proxy-arp
ip route-cache flow
speed auto
no cdp enable
!
interface FastEthernet0/0.1
description Data
encapsulation dot1Q 1 native
ip address 10.10.1.1 255.255.255.0
no ip redirects
no ip unreachables
no ip proxy-arp
no cdp enable
!
interface FastEthernet0/0.172
description Voice
encapsulation dot1Q 172
ip address 172.16.1.1 255.255.255.0
no ip redirects
no ip unreachables
no ip proxy-arp
no cdp enable
!
interface FastEthernet0/1
no ip address
speed auto
!

 

[snootalope]

ok..just sitting here looking at this, i've already got the subinterfaces setup, why couldn't I run one cable from e0/0 to one switch, and e0/1 to the other, wouldn't that accomplish my goal here? (and then I'd bind the switches as well)