Red Hat Satellite engineering is moving the tracking of its product development work on Satellite to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "Satellite project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs will be migrated starting at the end of May. If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "Satellite project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/SAT-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Description of problem:
Registration of CentOS 8 & RHEL 8 hosts that are already subscribed to another instance (or to cloud) fails with following error:
```
Unregistering from: satellite.example.com
Unable to verify server's identity: [SSL: TLSV1_ALERT_UNKNOWN_CA] tlsv1 alert unknown ca (_ssl.c:897)
```

Version-Release number of selected component (if applicable):
6.10

How reproducible:
* CentOS 8 and RHEL 8 only that are already subscribed somewhere else

Steps to Reproduce:
1. Try to register already subscribed CentOS 8 / RHEL 8 machine


Actual results:
Registration fails with error:
```
Unregistering from: satellite.example.com
Unable to verify server's identity: [SSL: TLSV1_ALERT_UNKNOWN_CA] tlsv1 alert unknown ca (_ssl.c:897)
```

Expected results:
Machine successfully registered.

Additional info:
Registration template should run `subscription-manager clean` command when `--force` parameter is `true`

Created redmine issue https://projects.theforeman.org/issues/33540 from this bug

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 (Moderate: Satellite 6.10 Release), 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/RHSA-2021:4702