[Samba] Demote a dead PDC: residuals in "DNS" console

[Ole Traupe]

Hi,

I demoted my PDC (DC1) forcefully, because replication (among others) 
wasn't working anymore due to hard disk failure and I was afraid of 
spending a lot of time on nothing.

With DC1 offline I seized the FSMO roles on DC2 (4.2.5), restarted 
Samba, and found errors in the samba log due to the missing DC1.

I removed the two DNS entries created according to this site:
https://wiki.samba.org/index.php/Check_and_fix_DNS_entries_on_DC_joins
I applied the script suggested here:
https://wiki.samba.org/index.php/Demote_a_Samba_AD_DC
This removed the DC1 entry in ADUC and "Active Directory Sites and 
Services".

However, the error persists (10 minute interval; sanitized):
# /usr/local/samba/sbin/samba_dnsupdate: couldn't get address for 
'dc1.my.domain.de': not found

Likely due to further DNS entries, the last-mentioned site suggests to 
remove them by hand. Most of the containers in the DNS console have only 
duplicate entries for DC1/2, so no problem. However, 3 don't:


(removed subfolder and client PC entries; sanitized, translated where 
necessary GR->EN)


*DNS/DC2/Forward-Lookupzones/my.domain.de*

Name    Type    Data    Time stamp
(identical to parent folder)    Source of Authority (SOA)    [3], 
dc1.my.domain.de., hostmaster.my.domain.de.    ?28.?10.?2015 15:00:00
(identical to parent folder)    Nameserver (NS) dc1.my.domain.de.    Static
(identical to parent folder)    Host (A)    IP__of__DC1    Static
(identical to parent folder)    Host (A)    IP__of__DC2    Static
DC2    Host (A)    130.149.34.118    ?29.?07.?2015 13:00:00


*DNS/DC2/Forward-Lookupzones/_msdcs.my.domain.de*

(identical to parent folder)    Source of Authority (SOA)    [3], 
dc1.my.domain.de., hostmaster.my.domain.de.    ?28.?10.?2015 15:00:00
(identical to parent folder)    Nameserver (NS) dc1.my.domain.de.    Static
objectGUID__of__DC2    Alias (CNAME)    DC2.my.domain.de. ?29.?07.?2015 
13:00:00


*DNS/DC2/Forward-Lookupzones/_msdcs.my.domain.de/pdc/_tcp*

_ldap    Service Identification (SRV)    [0][100][389] 
dc1.my.domain.de.    Static


What to do in these cases? Is it safe to open the properties of the 
non-duplicate entries and replace DC1 with DC2?

Ole