GTM & LTM implementation troubles

Just thinking through what I think you are trying to accomplish:

 

 

create two virtual servers: Global Traffic->Servers->LTM->Virtual Servers->Add

 

 

name ISP1, address 100.100.100.10, translation 10.10.10.11

 

name ISP2, address 200.200.200.20, translation 10.10.10.11

 

 

Create pool with both virtual servers, create wip with the pool.

 

 

Obviously this needs to be tested, but if GTM complains or doesn't work due to mapping to the same LTM vip, you could always create a duplicate vip on the LTM for the server pool.