Image upload fails for undercloud because swift object server cannot start when X server is running in Red Hat OpenStack Platform

Issue

Issue summary

We've noticed that the X Window Server is erroneously listening on port 6000, whereas it didn't in previous releases.

The X Window server is not honoring DisallowTCP=true set in /etc/gdm/custom.conf, can this be fixed?

Security scan is failing against xorg as it is now listening on port 6000.

I can't disable port 6000 listening on xorg.

The X Window server is conflicting with the Swift service on the undercloud of my Red Hat OpenStack Platform.

Issue details

One can see that image upload fails for undercloud because swift object server cannot start when X server is running in Red Hat OpenStack Platform

openstack overcloud image upload --image-path /home/stack/images/
500 Internal Server ErrorFailed to upload image <UUID>   (HTTP 500)

systemctl list-units shows:

* openstack-swift-object.service                                                                                                   loaded failed failed    OpenStack Object Storage (swift) - Object Server

And journalctl reports a port conflict for port 6000:

swift-object-server[50698]: Exception: Could not bind to 172.16.50.1:6000 after trying for 30 seconds

netstat -lntp | grep 6000 shows:

tcp        0      0 0.0.0.0:6000            0.0.0.0:*               LISTEN      0          93641      25107/X              off (0.00/0/0)