[Samba] Error changing server IP address: ERROR: Connecting to DNS RPC server

[Rowland penny]

On 08/05/2020 17:38, Lorenzo Milesi via samba wrote:
> Samba Version 4.12.1
>
> I'm trying to change server IP address from 10.0.0.69 to .3 on a single AD DC running also as fileserver (very small situation). I'm following this [1] guide, I have no interface restrictions in samba or in bind. I stop samba, change IP address, restart bind, start samba, but when I run samba_dnsupdate I get some messages until:
Double check that you do not have the old ipaddress anywhere.
> 5 DNS updates and 5 DNS deletes needed
> Failed to get Kerberos credentials, falling back to samba-tool: kinit for FILESERVER$@WDC.MYDOMAIN.IT failed (Cannot contact any KDC for requested realm)
>
> update (samba-tool): A fileserver.wdc.MYDOMAIN.it 10.0.0.69
> Calling samba-tool dns for A fileserver.wdc.MYDOMAIN.it 10.0.0.69 (delete)
> Calling samba-tool dns delete -k no -P ['10.0.0.3', 'wdc.MYDOMAIN.it', 'fileserver', 'A', '10.0.0.69']
> ERROR: Connecting to DNS RPC server 10.0.0.3 failed with (3221225653, '{Device Timeout} The specified I/O operation on %hs was not completed before the time-out period expired.')
> Failed 'samba-tool dns' based update of A fileserver.wdc.MYDOMAIN.it 10.0.0.69
> update (samba-tool): A wdc.MYDOMAIN.it 10.0.0.69
> Calling samba-tool dns for A wdc.MYDOMAIN.it 10.0.0.69 (delete)
> Calling samba-tool dns delete -k no -P ['10.0.0.3', 'wdc.MYDOMAIN.it', '@', 'A', '10.0.0.69']
>
> And here starts looping between different records update, failing with the same timeout error.
>
>
> /etc/resolv.conf:
> nameserver 127.0.0.1
> search wdc.mydomain.it
Change '127.0.0.1' to 10.0.0.3
>
> /etc/krb5.conf
> [libdefaults]
>          default_realm = WDC.MYDOMAIN.IT
>          dns_lookup_realm = false
>          dns_lookup_kdc = true
You only need the above in /etc/krb5.conf
> /usr/local/samba/var/log.samba
> [2020/05/08 18:30:05.360609,  0] ../../source4/dsdb/dns/dns_update.c:86(dnsupdate_nameupdate_done)
>    dnsupdate_nameupdate_done: Failed DNS update with exit code 110
That is a timeout

If all else fails try running the 'samba-tool dns' commands manually for 
the DC.

Rowland