Comment 5 for bug 1881642

According to man pages https://linux.die.net/man/8/pam_nologin - this occurs if the /etc/nologin file exist and is readable. I don't see this file nor the /etc/pam.d in [0] and [1]. Maybe not all files from /etc are collected, so this needs to be reproduced to troubleshoot more.

[0]: https://logserver.rdoproject.org/openstack-periodic-latest-released/opendev.org/openstack/tripleo-ci/master/periodic-tripleo-ci-centos-8-ovb-1ctlr_2comp-featureset020-ussuri/10d4b2a/logs/overcloud-novacompute-0/
[1]: https://logserver.rdoproject.org/openstack-periodic-latest-released/opendev.org/openstack/tripleo-ci/master/periodic-tripleo-ci-centos-8-ovb-1ctlr_2comp-featureset020-ussuri/10d4b2a/logs/overcloud-novacompute-1