While applying patch to primary the replica did not take authentication requests

[JamesAschinger]

We recently deployed a replica instance and today I applied 8.4 patch 14 to both servers. I started with the primary and while that was upgrading we were unable to authenticate to the replica. However it appears the replication is "Synchronized" and everything else appears good. 

[GeorgeMaher]

Hello James,

If we are dealing with Radius Authentications, you needed to make sure that the Ip of the replica is configured on the third party side, else it will not redirect the authentications,

Can you clarify more what was the agent type and if you are sure that the replicas are configured on the third party clients 

Thanks,

Gee