stuart test blog

This is a bit old, but as I recently learned, when Citrix released Metaframe Presentation Server 3 they introduced a new feature called Session Reliability. Briefly, Session Reliability allows your ICA sessions to remain active even when the network connectivity drops out. It seems like a good feature so why would you not use it? Well, there’s no reason not to use it – but you need to be aware that if you enable Session Reliability, any client that is version 8.1 or newer will now use port 2598 instead of 1494.

This is a huge change and unfortunately it doesn’t seem to be that well documented, or if it is documented it should be clearly highlighted in huge, bold, red letters! The reason why this is so important..? Most Citrix environments need to know the ICA port numbers in use so that the ICA traffic can be prioritised and also to be able to open ports on the firewall if necessary. If you’ve recently upgraded from MetaFrame XP to PS3 or PS4 then you should definitely ensure that you have the correct ports in use on your firewalls.

Brian Madden has a brief write up in this article too: Goodbye 1494, Hello 2598!