Description of problem:

Uninstalling IPA after it was installed without DNS results in a failure because named group is missing:

# ipa-server-install --uninstall --unattended
Forcing removal of servername
Failed to cleanup servername DNS entries: no such entry
You may need to manually remove them from the tree
----------------------------------------------------------------------
Deleted IPA server "servername"
----------------------------------------------------------------------
Shutting down all IPA services
Unconfiguring CA
group 'named' not found
The ipa-server-install command failed. See /var/log/ipaserver-uninstall.log for more information


Version-Release number of selected component (if applicable):

# rpm -q ipa-server
ipa-server-4.9.0-0.5.rc3.module+el8.4.0+9124+ced20601.x86_64

# dnf module info idm
Updating Subscription Management repositories.
Unable to read consumer identity

This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.

Last metadata expiration check: 1:07:39 ago on Mon 21 Dec 2020 08:40:27 PM UTC.
Name             : idm
Stream           : DL1 [e] [a]
Version          : 8040020201211123410
Context          : 1f8cbe47
Architecture     : x86_64
Profiles         : adtrust, client, common [d], dns, server [i]
Default profiles : common
Repo             : rhel-8.4-appstream
Summary          : The Red Hat Enterprise Linux Identity Management system module


How reproducible:
seems consistent

Steps to Reproduce:
1. dnf -y module enable idm:DL1
2. dnf -y module install idm:DL1/server
3. ipa-server-install --realm=TESTRELM.TEST --ds-password=Secret123 --admin-password=Secret123 --unattended
4. ipa-server-install --uninstall --unattended

Actual results:
Fails with message:

group 'named' not found

Expected results:
ipa uninstalled cleanly with no failures.

Additional info:

simply adding the system user named before uninstall works around the issue.