Has anyone seen this? we've been investigating a issue on our citrix farm, it's been there on 2308, 2311 and 2402. We have vdas going unregistered with failure reason Agent Requested. We're running pvs in this environment. The only error I see in eventviewer is The Citrix Desktop Service is re-registering with the DDC: 'NotificationManagerNotificationServiceThread WCF failure or rejection by broker

Which Windows version? We had this problem on Windows Server 2016 every time an administrator did an RDP reconnect.

We run server 2022 on the entire citrix environment, and it happens on servers without any admins logging on to them. I can see the events being logged in ControlUp

We've never been able to reproduce this issue on any version other than WS2016. So it's irrelevant 🙂

I would recommend to take CDF traces on the VDA and Delivery controller and open a support case

The challenge with getting cdf traces is that it happens randomly on any of the 150 CVAD servers we have, and at random times. I'll try to catch traces the next time I see it happen.

And when you reboot them they are fine? Sounds like they loose their trust with AD. Next time it happens see if you can still login to the session host

Don't need to reboot them, they only loose connection for about a second. It actually happened to a server 10 minutes ago, first at 222551. The Citrix Desktop Service is re-registering with the DDC: 'NotificationManagerNotificationServiceThread WCF failure or rejection by broker , then the same second The Citrix Desktop Service successfully obtained the following list of 2 delivery controller(s) with which to register and then The Citrix Desktop Service successfully registered with delivery controller. No issues logging on to the servers after the events. • I actually see in the release notes for 1912 CU1, the following is listed as fixed issue: Attempts to launch an application might fail. As a result, session details under Task Manager cannot be found and the following application status in Citrix Studio appears: application not running. When the issue occurs, the VDA might reregister and the following error message appears: • Event ID 1048: WCF Failure or Rejection by Broker • [CVADHELP-12856] https://docs.citrix.com/en-us/citrix-virtual-apps-desktops/1912-ltsr/whats-new/cumulative-update-1/fixed-issues.html Which is the same as I see in the logs, only problem is that we are running 2402.

Are you using the 2402 vda and broker or some other mix?

2402 all the way, brokers, vda, pvs, pvs agent, storefront, upm.

K ill search cases tomorrow to see what I can find

I've seen most of the cases too, noticed some blocks in our firewall earlier today, so going to investigate those further before I make a case