[Samba] Device ends up with multiple dns records and IP addresses

[Sebastian Arcus]

On 09/11/2021 14:29, Rowland Penny via samba wrote:
> On Tue, 2021-11-09 at 13:08 +0000, Sebastian Arcus via samba wrote:
>>
>> I have just checked this server today, and the printer has two IP
>> addresses again:
>>
>>
>> # host SEC001599AB9439
>> SEC001599AB9439.ihs-uk.lan has address 192.168.51.235
>> SEC001599AB9439.ihs-uk.lan has address 192.168.51.229
>>
>>
>> There are some other hosts with multiple IP's - an iPhone has 5 IP
>> addresses.
>>
>> I then went to test manually adding a record with two IP addresses
>> to
>> the dns server using the dhcp-dyndns.sh script:
>>
>>
>>
>> /etc/dhcpd.d# ./dhcp-ddns.sh add 192.168.51.200 abcdef test1
> 
> What OS is this running on ?
> I do not recognise '/etc/dhcpd.d'
> 
>>
>> However, by inserting debug statements, I discovered that the line
>> above
> 
> Can you supply the script line that crashes for you.

Ok - I might have a bit more useful information. I've added lots of 
debug lines in the script and the source of the error messages seems to 
be two fold: if there is already an A record in the dns back-end with 
multiple IPs, and/or a PTR record with multiple hostnames, both the 
corresponding "samba-tool dns delete ..." statements fail with those 
errors. Then everything snowballs down the hill, as every time the 
device gets a new IP address, the script keeps on adding more multiple 
records to the database, with no chance of recovering from there.

I still don't know for sure how did the multiple records happen in the 
first place. I do know however why I was still getting the error after 
deleting all the IPs in the dns back-end for this printer - it's because 
I didn't realise that there was also a PTR record with multiple 
hostnames, as well as the A record with multiple IPs.

Does the above help a bit? I don't know if the script should be changed 
to recognise multiple IP's / hostnames being returned when querying the 
dns back-end - and cope with that scenario? Or maybe that should just 
never ever happen in the first place?