We are having an intermittent connection issue and have gone through several troubleshooting steps with our vendor, Citrix and Wyse support. We are running out of ideas and are hoping it's not a firmware issue on the Wyse client. I thought I'd put it out to the experts and see if any of you can help. Here's what's going on:
We have a new Citrix Xendesktop 7 deployment for nonpersistant VDI desktops (workstation OS) and a few applications (server OS). We are using the newest Citrix Storefront to server up the web interface connections. We have 2 Storefront servers and 2 Delivery Controllers that are load balanced using round robin dns entries. We also use Profile Unity to manage several profile, registry and GPO options. Citrix servers are built on Windows Server 2012 r2 and the clients are Windows 7 x64.
All connections originating from a browser on a fat client work 100% of the time. Chrome, IE, and Firefox on Windows 7, 8 and 8.1 work every time. Fast and reliable.
The problem is when we connect using one of 250 Wyse Xenith c00x zero clients. Intermittently, when connecting on the latest firmware (and the previous one) after entering login credentials the connection never happens and the terminal reboots (which is it set to do at logoff). I'd say about 80% of the time we have no issue, but that's obviously unacceptable for a production environment. There are no errors in the Citrix Servers event logs, none in the Wyse terminal and no errors on the screen for the user. after a failed attempt future attempts will continue to fail. this will last anywhere from 1 minute up to 20 minutes of repeated failed login attempts and then suddenly it will work. If the user has a failed login and then goes to a fat client and logs in it will be successful and they can then log out and return to the Wyse client and log in successfully. Weird I know.
When a failed connection happens there is no record in the Delivery Controller (checked using Get-BrokerConnectionLog -Sortby establishmenttime). Also, there is no record in the Director Studio of a hung session or connection attempt.
We have tried firmware versions 2.0_105 and 2.0_210 which are the only 2 that support Citrix Xendesktop 7 and Storefront. The issue is present in both firmware versions. We are not running Storefront in Legacy mode, but we have tried that too, to no avail. We have checked, double checked, triple and quadruple checked the .ini file for the Wyse terminals and the settings have been confirmed as correct by Wyse. We also tried several settings and combinations that seemed to make sense but they all made no difference.
We have removed one of the Storefront servers and Delivery Controllers to eliminate the possibility of a load balancing issue, even though EVERY connection though the web interface yields a positive result.
We have tried several other things that escape me currently but I will be glad to give more specifics to any questions you may have.