[Samba] Remove stale DRS replication partner

[Johannes Engel]

Dear list,

After (almost) successfully removing a dead DC from my domain I am left
with only one visible symptom:
samba-tool drs showrepl shows two stale outbound link for one of the
remaining 2 DCs:
DC=DomainDnsZones,DC=subdom,DC=mydom,DC=com
        NTDS DN: CN=NTDS
Settings\0ADEL:09210f3d-dab9-4a69-92ca-b11e93845367,CN=DC3\0ADEL:591e8395-a414-4bca-99a0-8cb195417493,CN=Servers,CN=Location,CN=Sites,CN=Configuration,DC=subdom,DC=mydom,DC=com
                DSA object GUID: 09210f3d-dab9-4a69-92ca-b11e93845367
                Last attempt @ Mon Jun 26 17:26:27 2017 CEST failed, result
2 (WERR_FILE_NOT_FOUND)
                2001797 consecutive failure(s).
                Last success @ Sat Jan  7 15:22:31 2017 CET

I tried already the samba-tool emergency way using
DC2# samba-tool domain demote
--remove-other-dead-server=09210f3d-dab9-4a69-92ca-b11e93845367
ERROR: Demote failed: DemoteException: 09210f3d-dab9-4a69-92ca-b11e93845367
is not an AD DC in subdom.mydom.com

Same using the server's name instead of the GUID.
How can I remove this connection from the replication?

Any help appreciated.

Best regards
Johannes