samba - Oct 2024 - AD/DNS: Cannot Create a CNAME record with a blank name...

...as recommended on the Samba Wiki here: 
https://wiki.samba.org/index.php/Active_Directory_Naming_FAQ#I_have_to_Use_Different_Names_to_Resolve_Host_Names_Internally_and_Externally

I'm trying to use the "clever trick" to make a certain internal
server
resolve to the name I'm forced to use to resolve it externally. I 
successfully created the new zone (fictionalizing the names for 
inclusion here):

~ # samba-tool dns zonecreate "dc1" "myserver.example.com"
-U administrator
Zone myserver.example.com created successfully

...but I get a runtime error when I try to create the CNAME record in 
the zone "...leaving the name of the record blank." Here's what I
did:

~ # samba-tool dns add "dc1" "myserver.example.com"
"" CNAME
"myserver.samdom.example.com"? -U Administrator
ERROR(runtime): uncaught exception - (1383, 'WERR_INTERNAL_DB_ERROR')
 ? File "/usr/lib/python3.12/site-packages/samba/netcmd/__init__.py", 
line 279, in _run
 ??? return self.run(*args, **kwargs)
 ?????????? ^^^^^^^^^^^^^^^^^^^^^^^^^
 ? File "/usr/lib/python3.12/site-packages/samba/netcmd/dns.py", line 
1186, in run
dns_conn.DnssrvUpdateRecord2(dnsserver.DNS_CLIENT_VERSION_LONGHORN,
 ? File "/usr/lib/python3.12/site-packages/samba/netcmd/dns.py", line 
119, in f
 ??? return attr(*args)
 ?????????? ^^^^^^^^^^^
Have I misinterpreted the instructions and done it wrong? Thanks in 
advance for the help.

- John

On Fri, 11 Oct 2024 20:25:00 -0400
"John R. Graham via samba" <samba at lists.samba.org> wrote:
> ...as recommended on the Samba Wiki here: 
>
https://wiki.samba.org/index.php/Active_Directory_Naming_FAQ#I_have_to_Use_Different_Names_to_Resolve_Host_Names_Internally_and_Externally
> 
> I'm trying to use the "clever trick" to make a certain
internal
> server resolve to the name I'm forced to use to resolve it
> externally. I successfully created the new zone (fictionalizing the
> names for inclusion here):
> 
> ~ # samba-tool dns zonecreate "dc1"
"myserver.example.com" -U
> administrator Zone myserver.example.com created successfully
> 
> ...but I get a runtime error when I try to create the CNAME record in 
> the zone "...leaving the name of the record blank." Here's
what I did:
> 
> ~ # samba-tool dns add "dc1" "myserver.example.com"
"" CNAME
> "myserver.samdom.example.com"? -U Administrator
> ERROR(runtime): uncaught exception - (1383,
'WERR_INTERNAL_DB_ERROR')
>  ? File
"/usr/lib/python3.12/site-packages/samba/netcmd/__init__.py",
> line 279, in _run
>  ??? return self.run(*args, **kwargs)
>  ?????????? ^^^^^^^^^^^^^^^^^^^^^^^^^
>  ? File "/usr/lib/python3.12/site-packages/samba/netcmd/dns.py",
line
> 1186, in run
> dns_conn.DnssrvUpdateRecord2(dnsserver.DNS_CLIENT_VERSION_LONGHORN,
>  ? File "/usr/lib/python3.12/site-packages/samba/netcmd/dns.py",
line
> 119, in f
>  ??? return attr(*args)
>  ?????????? ^^^^^^^^^^^
> Have I misinterpreted the instructions and done it wrong? Thanks in 
> advance for the help.
> 
> - John
> 
You might just be the first to try this, I wasn't really aware of that
particular faq, but now I look at it, I wonder if it ever worked ?

I think your problem lies in that 'samba-tool dns add' requires 5
arguments:

'server' 'zone' 'name' 'rtype' 'data'

Because you are supplying 'name' as "", it is being treated as
if it
isn't there, so 'samba-tool' is seeing:

'server' 'zone' 'rtype' 'data'

Which is wrong. 
This may have worked with python2, but it doesn't appear to work with
python3 (I know, I tried and got the same error as you).

The thing is, your AD domain shouldn't be accessible externally, so
what is the 'certain internal server' you need to access ?

Rowland

On 12-10-2024 02:25, John R. Graham via samba wrote:
> ...as recommended on the Samba Wiki here: 
>
https://wiki.samba.org/index.php/Active_Directory_Naming_FAQ#I_have_to_Use_Different_Names_to_Resolve_Host_Names_Internally_and_Externally
>
> I'm trying to use the "clever trick" to make a certain
internal server
> resolve to the name I'm forced to use to resolve it externally. I 
> successfully created the new zone (fictionalizing the names for 
> inclusion here):
>
> ~ # samba-tool dns zonecreate "dc1"
"myserver.example.com" -U
> administrator
> Zone myserver.example.com created successfully
>
> ...but I get a runtime error when I try to create the CNAME record in 
> the zone "...leaving the name of the record blank." Here's
what I did:
>
> ~ # samba-tool dns add "dc1" "myserver.example.com"
"" CNAME
> "myserver.samdom.example.com"? -U Administrator
> ERROR(runtime): uncaught exception - (1383,
'WERR_INTERNAL_DB_ERROR')
> ? File
"/usr/lib/python3.12/site-packages/samba/netcmd/__init__.py",
> line 279, in _run
> ??? return self.run(*args, **kwargs)
> ?????????? ^^^^^^^^^^^^^^^^^^^^^^^^^
> ? File "/usr/lib/python3.12/site-packages/samba/netcmd/dns.py",
line
> 1186, in run
> dns_conn.DnssrvUpdateRecord2(dnsserver.DNS_CLIENT_VERSION_LONGHORN,
> ? File "/usr/lib/python3.12/site-packages/samba/netcmd/dns.py",
line
> 119, in f
> ??? return attr(*args)
> ?????????? ^^^^^^^^^^^
> Have I misinterpreted the instructions and done it wrong? Thanks in 
> advance for the help.
I have a similar need, but I create an A record at zone level with:

samba-tool dns add localhost myserver.example.com myserver.example.com A 
10.2.3.4 -U Administrator

The trick is to specify zone-name and record-name with the same value.
I have not tried to create a CNAME but given the syntax above that 
should be:

samba-tool dns add localhost myserver.example.com myserver.example.com 
CNAME?myserver.samdom.example.com -U Administrator

If it turns out that it does not work with a CNAME record, I would guess 
an A record also solves the issue.

- Kees.
>
> - John
>
>
>