The question is in regards to the Transmission Control Protocol (TCP) reconnect timeout. We have two Data-centers with APM pairs at each site and the DNS on the GTM. The issue is when both the APM's fails the edge-client is talking 15 minutes to before it makes a new DNS call to the GTM. Unless the new request is made the edge client will be in the Reconnect state.
After the site switch-over, i was able to connect to the other with the new connections. However , the issue is for the users who doesnt disconnect the edge client manually when the site is completely down.
As per the F5 documentation,
Transmission Control Protocol (TCP) reconnect timeout—The maximum amount of time BIG-IP Edge
Client can attempt to reconnect a VPN tunnel using a valid session. The period is hard-coded to 15