Part 12: Working with Citrix XenApp 6.5 – Managing Sessions [2/2]

Session Reliability
Session reliability helps improve the connection for users. The reason why we would use session reliability is if the users who access the XenApp applications are in a remote location with poor internet connectivity, wireless connections that might drop from time to time, and so on. What session reliability does, is if the user looses network access temporarily, the session is kept active until the user reconnects and it does so without prompting the user for his/her credentials.
We can manage session reliability through Citrix Computer Policies

These polices are:

• Session reliability connections – Keeps sessions active when network connectivity is interrupted
• Session reliability port number – TCP port number for incoming session reliability connections
• Session reliability timeout – The length of time in seconds the session reliability proxy waits for a client to reconnect before allowing the session to be disconnected

Client Reconnection
We can configure Auto Client Reconnect so that if the sessions are monitored by the Citrix plugins and if the connection gets disconnected or breaks, the plugin will automatically fix the issue by reconnecting the session without having to involve the user. We do have policies in place to control Auto Client Reconnect

The policies are:

• Auto Client Reconnect – Allows or prevents automatic reconnection by the same client after a connection has been interrupted
• Auto client reconnect logging – Records or prevents recording auto client reconnections in the event log

ICA Keep-Alive Packets
We can configure ICA Keep-Alive packets which prevents some connections from disconnecting. What happens is XenApp server will send what is called a Keep-Alive packet every couple of seconds to make sure the session is alive, kind of like we do with some VPN connection. Now, if the session is not active, in other words the user left home for the day and forgot to log-off his/her session, then XenApp is smart enough to know, that the session can be disconnected. It is worth noting that if Session Reliability is enabled, then Keep-Alive won’t work as Session Reliability has its own mechanism for doing this. Again, just like other session options, we can configure Keep-Alive settings within the policies of the servers

The description of the polices are:

• ICA keep alive timeout – Seconds between successive ICA keep-Alive messages (60 seconds by default)
• ICA keep alives – Sends or prevents sending ICA keep-alive messages periodically

It’s important to note that the ICA settings override the Windows Group Policy settings