Hi all,

we want to use a F5 loadbalancer in front of two nginx instances, which balance the load to our app-nodes.

The F5 loadbalancer distributes incoming requests via round-robin algorithm to the two nginx instances.

The nginx instances should be configured to use ip_hash to distribute the requests to the addnodes ensuring sticky sessions. Specific customer requirements make the use of cookies to ensure sticky sessions impossible.

I understand, that all nginx instances use the same function to hash the IP adress. But i am not sure if the distribution of the hash values to the appnodes happens in a consistent way.

I came across the following discussion on github which indicates that the same IP address may be forwarded to different appnodes in the scenario described above:

http://serverfault.com/questions/511763/do-multiple-nginx-servers-load-balance-the-same-ip-address-to-the-same-backend-w

Long story short / tl;dr:

Will different nginx instances forward requests from the same IP always to the same appnode when using ip_hash as a load balancing method?

Thanks,