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nineheadbird_67's avatar
nineheadbird_67
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Nov 11, 2009

multiple subnets within a vlan not allowed?

We have 6900 LTM connected to Cisco router, on cisco end, there are four subnets on interface vlan 299(see below). Tagged interface 299 from cisco to F5 configured as vlan external on F5, and there ar...
config
design
boomchke_11156's avatar
boomchke_11156
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Aug 03, 2011
Looks like Im a little late to the conversation but Jason seems to have hit the nail on the head. I've being doing Cisco for a long time and have never found a good use for the 'secondary IP address' command. Its bad design in my mind. The configuration should be a trunk between the two either with SVI interfaces (VLAN interfaces) on the switch or sub interfaces on a router (router on a stick) if your Cisco doesnt support L3 switching. The general rule of thumb shoudl always be one subnet per one vlan.

 

 

Wintrode - Multiple subnets can exist on the same VLAN however its poor design. When you say 'TAG' are you referring to the Cisco side of things or the F5 side of things?