Bug 1790443

From the information provided by jgrulich, I gathered this reproducer for the verification:

Some important notes:
1) You cannot start a service for a user who is currently logged in
(graphically)

2) Make sure you remove old service files which previously had to be copied to
/etc/systemd/system as these will be loaded first and it will obviously fail.
The new service file is in /usr/lib/systemd/system.

Setup:
1)
$ sudo semodule -i /usr/share/selinux/packages/vncsession.pp
$ sudo restorecon /usr/sbin/vncsession /usr/libexec/vncsession-start

2) Add displays and usernames to /etc/tigervnc/vncserver.users
# echo ":22=test" >> /etc/tigervnc/vncserver.users
# cat /etc/tigervnc/vncserver.users
....
:11=test
:22=test2

3) Set desktop for GNOME
# echo "session=gnome" >> /etc/tigervnc/vncserver-config-defaults

4) start the vnc server for user test2
$ sudo systemctl daemon-reload 
$ sudo systemctl start vncserver@:22

5) Verify the service is running
$ sudo systemctl status vncserver@:22

Then was able to connect via vncviewer. I tested the lockscreen and it worked for me. 
Logging out via gnome-shell terminates the vncservice.

Hopefully I did not miss anything.

The new HOWTO doc is in the wrong directory:

~]# rpm -q tigervnc-server
tigervnc-server-1.10.1-4.el8.aarch64

~]# rpm -ql tigervnc-server | grep HOWTO
/usr/share/doc/HOWTO.md


I think it should be in /usr/share/doc/tigervnc/HOWTO.md

Also, removing the /usr/bin/vncserver command is rather jarring to users (it was to me, at least!).  Maybe you can create a new /usr/bin/vncserver script which points users to the new HOWTO doc?  Something like this:

~]$ cat /usr/bin/vncserver
#!/bin/bash
echo "vncserver has been replaced by a systemd unit."
echo "Please read /usr/share/doc/tigervnc/HOWTO.md for more info."

(In reply to Jeff Bastian from comment #8)
> Also, removing the /usr/bin/vncserver command is rather jarring to users (it
> was to me, at least!).  Maybe you can create a new /usr/bin/vncserver script
> which points users to the new HOWTO doc?  Something like this:
> 
> ~]$ cat /usr/bin/vncserver
> #!/bin/bash
> echo "vncserver has been replaced by a systemd unit."
> echo "Please read /usr/share/doc/tigervnc/HOWTO.md for more info."

That's quite a good idea. I will add something like that and fix installation of the HOWTO.md file.

There is now a new build of tigervnc, which:
1) Fixes installation of the HOWTO.md file
2) Installs /usr/bin/vncserver script which will tell the user to read the HOWTO.md file

The new build looks good.  Thanks!

[root@ci-vm-10-0-137-119 ~]# rpm -q tigervnc-server
tigervnc-server-1.10.1-5.el8.x86_64

[root@ci-vm-10-0-137-119 ~]# rpm -ql tigervnc-server | grep -e HOWTO -e bin/vncserver
/usr/bin/vncserver
/usr/share/doc/tigervnc/HOWTO.md

[root@ci-vm-10-0-137-119 ~]# vncserver
vncserver has been replaced by a systemd unit.
Please read /usr/share/doc/tigervnc/HOWTO.md for more information.

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (tigervnc bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2020:4683