Hi Shweta,
> I have an active HTTP session serviced through the haproxy's virtual ip > and load balanced to one of the virtual servers. If the master haproxy > instance goes down in the middle of the active HTTP session, can the > backup haproxy instance that takes over the virtual ip ,know that the > session was terminated in the middle ? Will it try to initiate a new > session with the other backend server without the user having to > intervene and start a new session at the front end ? No, there is no simply and efficient way to do that. > I currently see that, when the master haproxy instance goes down, the > active session is terminated. The backup haproxy instance takes over > the virtual ip and only when the user tries to establish a new session, > the backup haproxy connects the user to the backend server. Is this the > expected behavior ? Yes. > What is achieved through the "peers" and "stick-table" command here ? The content of the stick table is synchronized between the 2 haproxy instances, so when the failover, or in a active-active design a request hits a different haproxy instance, the informations in the stick-table are available. What that means exactly depends on what you are using the stick-table for. In your case, it seems you configured stick-tables and peer synchronization, but are not actually using it. Please see this article for an example to use client-ip persistence using stick-tables: http://blog.exceliance.fr/2013/04/22/client-ip-persistence-or-source-ip-hash-load-balancing/ Regards, Lukas
