With Lua just about anything is possible in this scenario, but the question should be:
what are you going to do with sticky session data when it falls over?
Stickiness is used to maintain and be consistent for one data session and its backend processor, a backup server may very well not know what to do with a session it knows nothing about or may even process the wrong data...
I'd suggest using Lua to perform health checks on your Sticky pool AND all active sticky sessions to each pool member, once a member is down you must expire all sticky sessions and maybe even do a rollback on sticky database sessions or implement a post completion mechanism.
The use of Sticky is explicit in its purpose and come with a few digital health warnings.
what are you going to do with sticky session data when it falls over?
Stickiness is used to maintain and be consistent for one data session and its backend processor, a backup server may very well not know what to do with a session it knows nothing about or may even process the wrong data...
I'd suggest using Lua to perform health checks on your Sticky pool AND all active sticky sessions to each pool member, once a member is down you must expire all sticky sessions and maybe even do a rollback on sticky database sessions or implement a post completion mechanism.
The use of Sticky is explicit in its purpose and come with a few digital health warnings.