LTM Connection to Dual Switches

You'd also have to check if LACP is supported across the two separate switches that you're using... Most likely not though. Very few do.

 

 

However if you're using something like Cisco 3750 series switches (e.g. 2x 3750E's) you can stack them to make a single LOGICAL switch, AND you can perform LACP across both of them... (LACP balancing modes on the 3750 are a bit limited though. Most of the 'cheaper' ones default to mac headers rather than using IP src/dest/ports and full IP hashing may not be available - Can't remember the complete list the 3750 supports).

 

 

However assuming you have the extra ports on the BigIP units you could do diagram 1 WITH lACP to each port... best of both worlds and rely on spanning tree for link availability (However that does mean you need a reconvergence when you lose a link which may be more disruption than you think is worth it).

 

 

I'l re-iterate what Nathan and Aaron said above.. use VLAN failsafe to ensure the units LTM failover if you lose VLAN connectivity for any reason.

 

 

 

[Note. You don't specify whether the switches are Layer-2 only, or if you have SVI's on them. You may want to think about GLBP vs HSRP for instance. Or even whether spending extra on something like a 6506 would be better economy than two separate switches in data centre, or even 2x6506's :) ].

 

 

H