ipa-server-upgrade fails when running the ipaload_cacrt plugin. The plugin
finds all CA certificates in /etc/httpd/alias and uploads them in LDAP
below cn=certificates,cn=ipa,cn=etc,$BASEDN.
The issue happens because there is already an entry in LDAP for IPA CA, but
with a different DN. The nickname in /etc/httpd/alias can differ from
$DOMAIN IPA CA.
To avoid the issue:
1/ during upgrade, run a new plugin that removes duplicates and restarts ldap
(to make sure that uniqueness attr plugin is working after the new plugin)
2/ modify upload_cacert plugin so that it is using $DOMAIN IPA CA instead of
cn=$nickname,cn=ipa,cn=etc,$BASEDN when uploading IPA CA.
https://pagure.io/freeipa/issue/7125
Reviewed-By: Fraser Tweedale <ftweedal@redhat.com>