Thread: 9.6.9 Default configuration for a default installation but differentwith-krb-srvnam

On Fri, 2019-04-26 at 13:18 +0000, Jean-Philippe Chenel wrote:
> 1. So my question is, how can I compile this version of postgresql (9.6.9) and have the same real things
> of the default previously installed version, but with the --with-krb-srvnam=POSTGRES_DEV to change the
> default user name? So one server will have the postgres user and the other one will have postgres_dev user.

You can run

  pg_config --configure

to see how PostgreSQL was configured.

> 2. I'm planning to shut down the postgresql service and then replace files generated by the make install
> command. After restarting the service, all will work  as expected with the same database objects that were running
before?

If you use the same major release and configured it identically on the same architecture, yes.

Yours,
Laurenz Albe
-- 
Cybertec | https://www.cybertec-postgresql.com

Greetings,

* Jean-Philippe Chenel (jp.chenel@LIVE.CA) wrote:
> I've configured the GSSAPI authentication with MS Active Directory and it works very well.

Glad to hear that.

> The problem is that we have a dev and prod environment and each server must be configured with gssapi again the
domaincontroller. The default user is "postgres" and it cannot be bound to both postgresql server at the same time to
thesame userPrincipalName on the Windows domain controller.
 

You should be able to just use a different user in AD for each server,
and then map 'postgres/dev.hostname@REALM' to the dev user and
'postgres/prod.hostname@REALM' to the prod user in AD and everything
should work just fine.

> 1. So my question is, how can I compile this version of postgresql (9.6.9) and have the same real things of the
defaultpreviously installed version, but with the --with-krb-srvnam=POSTGRES_DEV to change the default user name? So
oneserver will have the postgres user and the other one will have postgres_dev user.
 

You shouldn't need to compile with a different krb srvname (and I
wouldn't recommend that you do).  If you *really* want to have a
different srvname, you don't have to recompile anything if you update
your client and server side configs to match whatever you want the
srvname to be, but, again, you shouldn't need to do that and doing so is
just confusing (particularly building different binaries, since then
some binaries will think 'postgres' is the default srvname and some will
think 'whatever' is, while otherwise being the same...).

> 3. Maybe can we configure things differently, if something else can be done to make this work, I'm open to
suggestions.

Create different users in AD for each and then map to them.  You don't
need to have a different srvname.

Thanks,

Stephen

Greetings,

* Jean-Philippe Chenel (jp.chenel@LIVE.CA) wrote:
> If I understand, the mapping can be done in the pg_ident.conf file ?

No, you do the mapping in AD.

Look at the '/princ' and '/mapuser' options used in the ktpass command
here:

https://info.crunchydata.com/blog/windows-active-directory-postgresql-gssapi-kerberos-authentication

Thanks,

Stephen

Greetings,

* Jean-Philippe Chenel (jp.chenel@LIVE.CA) wrote:
> You're absolutely right, the mapping work very well.

Great, glad to hear it.

> I've created 2 "service user" on Active Directory (postgres and postgres_dev), and generated the keytab like this:
>
> ktpass -out postgres_pg1.keytab -princ postgres/PGDOMT1.ad.com@AD.COM -mapUser AD\postgres -pass 'UserPass1' -mapOp
add-crypto ALL -ptype KRB5_NT_PRINCIPAL 
>
> ktpass -out postgres_pg2.keytab -princ postgres/PGDOMT2.ad.com@AD.COM -mapUser AD\postgres_dev -pass 'UserPass2'
-mapOpadd -crypto ALL -ptype KRB5_NT_PRINCIPAL 

I would strongly suggest you use passwords that are randomly generated
and not sent to a public, archived, mailing list.  If someone knows the
password, they can impersonate the server.

Thanks!

Stephen