Horizon Clients (2012, 8.2.10, Windows10) reporting irregular black screens

[MatthiasPohl]

We have a clustered Horizon 7.13.0 environment, with several manual desktop pool. All machines are running Windows 10 with agent 7.13.0-16975066 installed.

Our clients connect via Devoltions RDP Manager to the machines. They are reporting irregular black screens. In some cases the problem is solved by rebooting the machine, in some cases a client reboot solves the problem. 

Any hints or recommendations? 

[fabio1975]

Ciao 

Usually, this problem is generated from a network problem (TCP/UDP PORTS not open etc..), do you have multiple Horizon Connection Server? Use the Unified Access Gateway? Do you have checked the Horizon Agent Log?

For the log check this: 

https://docs.vmware.com/en/VMware-Horizon-7/7.13/horizon-client-agent-security/GUID-2845973D-BE67-47...

[MatthiasPohl]

Hi Fabio,

we have two Connection Servers, and no UAG. We use a simple linux load balancer.

I´ve downloaded the debug*.txt, but found no problem, so far. 

Kind regards,

Matthias

[fabio1975]

Ciao 

A test, if it is possible for you, could be to stop one of the two connection servers and check if the problem exists (perform the stop on both connection servers in turn) so we understand if it is a problem with one of the two connection servers. Otherwise, simply connect not using the FQDN attested on the load balancer but using the name of the single connection server (also in this case trying on both)

[MatthiasPohl]

Hi Fabio,

I´ve disabled one Connection Server and after a few minutes we get "HTTP 500 - Internal Server Error". After re-enabeling the server everything works fine again.

When I disable the other connection server, we didn´t get the error message. I have disabled one connection server know, and monitor if we´re still facing black screen problems....

[MatthiasPohl]

Update: If we have one connection server disabled (it doesn´t matter wich) some colleagues get the error message "HTTP-Fehler 500" but not all colleagues.

[fabio1975]

Hi
is the load balancer, that you have in front of the connection servers, intelligent? realizes that one of the connection servers is down and does not send connections to it?

Bye 

[MatthiasPohl]

No, it is just a "stupid" debian system with a nginx load balancer

[sjesse]

How do you have it setup, if I had to guess users are not getting back to the correct server, you need some sort of session stickyness setup like mentioned here

https://warlord0blog.wordpress.com/2018/11/21/vmware-horizon-load-balancing/

[MatthiasPohl]

We plan to test some VMs connecting directly to one connection server. If this works fine, the loadbalancer is the problem. Then we´ll investigate on the load balancer.

[MatthiasPohl]

Okay, we don´t have a problem with our load balancer. The VMs with a direct connection via one connection server, behave the same way.

We always get a black screen, when we log off from windows (VM side) and try to open a new session. Then we close the session (close the horizon window), reconnect and everything works fine. 

So: no blackscreen when we only close the session, always blackscreen when we log off from windows. So perhaps we have to configure something inside the VM on windows side?

[Hmunning]

Hi Matthias,

Which VM Tools version do you have installed? VM Tools version 11.1.5 and higher installs an SVGA driver that is newer than the version that comes with the Horizon agent. We saw similar problems with multi-monitor setups.

Horizon agent 7.13 should have SVGA driver 8.16.7.8 5/14/2020 installed.

Take a look at this KB:

https://kb.vmware.com/s/article/2078739

[MatthiasPohl]

Hi,

we have VMware Tools 11.2.5.17337674 and SVGA driver 8.16.7.8 5/14/2020 installed

I followed the steps mentioned in the KB, but still the same problem.

Everytime the user logs off from windows, and tries to open a new session, we get a black screen. If we then close (just closing the horizon window) the session and reconnect, everything works fine...

[Ahelio]

I am dealing with the same issue across several of my clients.
View agent version 7.12 and 7.13.
We can't seem to find anything logical that makes sense, the machines freeze at random when a user logs off and tries to log back in the next morning. Black or blank screen and frozen VDI. 
I'm going to start digging through SVGA driver versions to see if that makes any sense, but if we have the user disconnect rather than log off, everything is fine.
It only occurs at log off / log on

[Yorick1]

Hello all,

We have exactly the same problem in our Horizon environment. The employees describe the procedure as the same as yours. After logging off or even shutting down the VM, they get a black screen the next day.

After upgrading to Horizon 8.2, the problems with random black screens started. The upgrade also included updating VMware Tools from 11.0.5 -> 11.2.5.

Have you already found a solution?

I have opened a case with VMware and hope to find a solution.

[MatthiasPohl]

Hi Yorick1,

no, we haven´t found a solution so far. But we opened a VMware SR. Could you please send me the SR-Number of your case? Perhaps it would be helpful, if the Support Engineer is aware of the other SR.

Kind regards,

Matthias

[Yorick1]

Hi Matthias,

the problem has disappeared for about a week, although we have not made any changes. I will leave the VMware case open until Monday.
I gladly send you the case number SR 21221332605.
Maybe it will help you.

Cheers,
Chris