This week’s Post of the Week is based on the post GTM and IP selection by poster cknail.  He was looking for a solution to hand out the same IP address for LTM virtual servers in different data centers, in support of devices that don’t honor the short TTL asserted by GTM.  After an interesting discussion by several F5 engineers regarding the interplay between LTM and GTM regarding monitoring VS status, it turns out that the best solution is LTM only with the ARM (Advanced Routing Module) licensed and configured to provide Route Health Injection based on LTM monitoring results for virtual server peers on a BGP or OSPF peering network.

F5 Solutions Architect Nathan McMahon explains Election Hash Load Balancing And Persistence (find the iRule in the codeshare here).  He developed this Election Hash solution to address the limitations of the Cache Array Routing Protocol, and it provides a nice alternative to any typical  hash solution that are vulnerable to re-factoring on changes to the server pool.  The complete solution is written up here: Hash Load Balancing and Persistence on BIG-IP LTM

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