Failover instead of Load Balancing Pool members?

The easiest way to get it done from my perspective works without an iRule.

Just apply destination address affinity to the virtual server.

Now check the persistence table:

watch -d -n 1 tmsh show ltm persist persist-records   

You will notice a single entry only. Traffic to the virtual server (persistence key) is balanced to selected pool member. No matter who the client is.

As soon as the pool member fails all incoming traffic will be directed to the alternative pool member and the persistence record will be updated.

That´s it. Obviously the feature was intended to be used in another context but it works pretty well for this particular purpose.

I actually started using it this way in BIG-IP v4.2. 🙂

Thanks, Stephan