SMLT equivilent in Cisco

[trey.greenwell]

We have two Cisco 2811's in VRRP. Each with 4 FE switching interfaces. We are wanting to connect these to two Cisco 3560's which distribute down to a few VMWare host boxes. I was looking for a SMLT equivilent for Cisco but have not been able to come up with anything to connect the switches/routers in a "mesh" to provide redundancy without having to get tangled up too much with STP.

We had a crazy idea to add all the ports into one channel group just for fun but I'm not too confident on that.

Any suggestions or direction would be greatly appreciated.

[Flintstone]

Hi trey.greenwell and welcome to the forum,

Probably the best idea would be to connect the Cisco switches together via Etherchannel and turn off STP?  Etherchannel the Cisco 2811's to each switch, so only one 2811 is connected to one 3560.  Then connect your VMWare hosts over both switches assuming you have two interfaces.  I believe you can setup the VMWare interfaces to Tx on both and Rx on one and failover to a single interface if you lose one?

This should give you the best redundancy without using STP, whether you lose a 2811 or a 3560?

CheerZ and good luck

[Jon Hurtt]

Agree with Flintstones. You will be unable to get the level of redundancy that SMLT (or MLAG) would provide with the Cisco 2811.

The best option outside of STP/RSTP/MSTP would be to using Ether-channel (802.3ad) from Cisco 2811 to Cisco 3560 and make the VMWare Host do an active-standby connection into each 3560.  This design has one flaw, if the Cisco 2811 that is connected to the 3560 on the Active Link Path fails, not sure how the VMWare Host will know to fail the link, I guess you would need some type of remote fault indication or some type of heartbeat with the VRRP Interface to inform the VMWare Host that its L2 Path is down.

Would also think that Active-Active Links from your VMWare Host would cause the same MAC to be located on two different ports from the perspective of the Cisco 23811, if that is true not sure if that is good network design.

 The only way to get Active-Active MLAG (something similar to Avaya's SMLT) from Cisco would be upgrading to Cat6500 (VSS) or Nexus 7K (vPC).

[Flintstone]

This design has one flaw, if the Cisco 2811 that is connected to the 3560 on the Active Link Path fails, not sure how the VMWare Host will know to fail the link, I guess you would need some type of remote fault indication or some type of heartbeat with the VRRP Interface to inform the VMWare Host that its L2 Path is down.

As long as the Cisco 3560's are connected together then the VRRP IP will failover to the other Cisco 2811, so as far as the VMWare host/hosts are concerned they can still get to their default gateway?

CheerZ

[Jon Hurtt]

This design has one flaw, if the Cisco 2811 that is connected to the 3560 on the Active Link Path fails, not sure how the VMWare Host will know to fail the link, I guess you would need some type of remote fault indication or some type of heartbeat with the VRRP Interface to inform the VMWare Host that its L2 Path is down.

As long as the Cisco 3560's are connected together then the VRRP IP will failover to the other Cisco 2811, so as far as the VMWare host/hosts are concerned they can still get to their default gateway?

CheerZ

Didn't realize the 3560s were connected to each other. I retract that statement

[rjenk]

Cisco's version of SMLT is call vPC (Virtual Port Channel) and it is available mainly on their chassis switching lines. 

We have almost completed a migration from two 8600's to two Nexus 7000's in our core and we are using vPCs to connect to our edge switches.  So far it is working really well.

[gplante]

A hardware alternative to going to a 6500 series running VSS or the Nexus 7k would be to look at a stackable switch. It you here looking to get similar performance with a small price increase you could look at a pair of 3750's. These are in the same performance group as the 3560 but allow you to have similar fuctionality to VSS or VPC. You just have to configure the two using the Stackwise technology.

This will allow you create PagP or LACP link between the routers and the switches. Also you could configure the servers with aggragated link to the switches. This also simplifies the management as the switch will appear as one logical device.

Greg