This issue can be seen mostly if the initial connection is going through Load Balancer to VIP.

If the connection is made directly to the Connection server IP / FQDN or UAG IP, it work fine.

Lets understand:

• The client sent "Last User Activity" parodically to the connection sever after specific set of time.
• Assume the LB as session timeout of 15 mins and Connection server or UAGs are being Load balanced.
• Client made Connection VIP and request goes to UAG1 or Connection Server1.
• After 15 mins, LB session timeout happened.
• At 25th min client send last user activity or heart beat to VIP. This time VIP re-route to Connection server2.
• Connection server 2 is not aware of the initial session and say, session expired.

Please give kudos if it help
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