What is wrong with this design?

The management port cannot be on the same network as load-balanced traffic. It is a NIC and not part of the switch fabric. So that's the first problem. You'll need to move the mgmt IP off the 10.6.100.x network.

 

 

Ideally, you should have the LTM set up as a Layer 3 device with it having an external and an internal VLAN, with the servers on the internal VLAN, and the LTM's internal self-IP as the server's gateway.

 

 

If that is not possible due to the need to re-IP servers and such, you could tag VLAN 100 on one of the switch ports (1.1 - 1.4) and set it up as a "one-armed" configuration, such that the virtual servers are also on the 10.6.100.x network with the real servers. However you will need to SNAT to get the routing to work in that configuration (SNAT Automap is usually easiest).

 

 

That should get you started, take a look on AskF5 for more configuration guides or post back if you need more help from that point.

 

 

Denny