Wired Intelligent Edge

In this scenario.. i see the interfaces connected between the switch pairs are showing up as LACP block.  They are configured as multichasis lag ports.

To make MC-LAG work, you need to meet certain requirements. One of it being VSX configured correctly with a common system-mac per VSX cluster. Furthermore, VSX shall be in-sync and MC-LAG interfaces need to have the correct physical interfaces as members. 

None of these things can be confirmed by just the diagram. So, kindly, post the output of the following commands (from all 4 switches):

• show vsx status
• show lacp interfaces
• show run vsx
• show run int lag XX (<-- where XX represents the LAG number of the links between the clusters)
• show run int 1/x/y (where 1/x/y represents the physical interfaces between the two clusters)
• show lldp neighbor

You may sanitize/strip down the output to relevant parts. 

Moreover, maybe that discussion can help, too: https://community.arubanetworks.com/discussion/arubaos-cx-switches-vsx-and-mc-lag

Regards, 
Thomas

If VSX and MC-LAGS on switches and port aggregations on servers are correctly configured and use the same protocol (LACP), then this scenario will work. Also check cabling as in my experience a lot of LACP block problems originate in wrong cable connections.

Best, Gorazd 

Please check your VSX system-mac! In most cases they are copied from one VSX cluster to another and in case of LACP it becomes a problem!

They have to be unique on each cluster.

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Greez,
Uli
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