[Progress Communities] [Progress OpenEdge ABL] Forum Post: RE: PASOE: sticky sessions for APSV and failover

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dbeavon

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Roy, I can confirm that it is the StateFree/SessionFree connections from the .Net openclient that are the most negatively affected when an HTTP session is lost. The sessions are easily lost when a PASOE instance behind the load-balancer is removed from service. Our openclients that use "SessionFree" connections will all start throwing exceptions, and many will crash, depending on the error-handling in that part of the app. The exception is often a very generic communication error and is not easily identified in code (ie its not a "SessionLostPleaseTryReconnectingException"). Interestingly, if the exception can be caught without crashing the app, the next attempt to use the same "SessionFree" connection will re-initialize properly and add a fresh HTTP session to the pool (which is now connected to a different PASOE instance behind the load-balancer) As a side note, It is somewhat counter-intuitive that an operating mode called "SessionFree" is the one that has the most problems when the underlying sessions are lost. ;)

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