Aggregate Link in standby mode

[pquiring]

I was adding a new VLAN today when our aggregate link between our two backdone switches designed to go into standby mode.  What would cause that?  Caused a "GREAT" deal of frustration today.  I've added other VLANs in the past without incident.

Our backdone switches are A5800.  The distribution switches vary.  All are HP.

I was trying to add a Guest VLAN that should NOT be routed.  How would I do that?  There needs to be an option to specify whether each VLAN should be routed.  I think I need ACLs or something?  Is there an easy way to do it in the web interface or should I just run seperate fibers for the guest network.  Kinda defeats the purpose of VLANs.

Thanks.

[16again]

On your only create the guest VLAN, but do not assign an IP addressing to it.
You'll end up with a good old layer2 VLAN without L3 routing capability

[Vince-Whirlwind]

Show us the core switch log for the period when this "standby mode" happened.