Topic: Citrix XenApp

[ddougan]

A new client of mine has SME Server in server/gateway mode. I had a call that they were having a problem downloading. It transpires that they are attempting to connect to a Citrix XenApp server hosted by a supplier, but were getting an error when trying to connect.

I emailed the company's support staff and was given two ports to open (1494/TCP and 1604/UDP); however, opening these did not resolve the issue. This evening, I connected a PC to my cable modem and ran Wireshark while attempting to connect to the application (which connected OK). Reviewing the Wireshark log shows port numbers in the 49000 range being the destination on my side of the communication - and of course, different attempts see different ports used.

Has anyone any experience with Citrix and the best way to configure for it? Opening ports willy-nilly appeals not... What I find odd is that none of the information I came across on the Citrix site mentions high ports - and in fact seems to indicate that XenApp should use only 80 and 443.

Thanks,

Des

[kruhm]

In my experience, there's probably something else going on that we're not aware of & you need to look in a different direction. Something is hindering communication that isn't the standard SME.

A client pc behind a sole SME GATEWAY should have no issues connecting to Citrix. SME doesn't block any outgoing ports (so "opening" ports isn't going to help).

This type of issue will happen with a double firewall or similar (local-->sme_gateway-->sonicwall). Or, on rare occasions, a router in between the client's network and the supplier's network has issues, dropping packets and causing a lack of connectivity.

[ddougan]

Thanks for your reply. The testing I did was on my own LAN - there is nothing between the cable modem and SME Server and therefore when I connected the modem directly to my test PC, Wireshark was monitoring point-to-point traffic.

As I noted, the remote Citrix box was attempting to connect to high-numbered ports on the client when monitored using Wireshark. That would indicate to me that the Citrix server is not well configured; however, not having any Citrix experience, that may not be the case. I'm still waiting to hear back from the company hosting the Citrix box.

Regards,

Des