Marcus Junius Brutus's questions

I have two postgresql installations:

$ sudo /etc/init.d/postgresql status
9.1/main (port 5432): online
9.2/main (port 5433): online

I was used to restarting the postgres database doing a:

$ sudo /etc/init.d/postgresql restart

... but now that there's two of them, how to choose which one to restart?

UPDATE: following the answer I received from Micah Yoder I did a:

/usr/lib/postgresql/9.2/bin/pg_ctl -D /var/lib/postgresql/9.2/main restart

which was met with "could not open PID file /var/lib/postgresql/9.2/main/main/postmaster.pid permission denied". When I tried to run pg_ctl in a sudo-i session I was met with:

pg_ctl: cannot be run as root
Please log in (using, e.g., "su") as the (unprivileged) user that will
own the server process.

How am I supposed to run the pg_ctl program? Also I don't see why I have to indicate the data file for a restart. Doesn't the process know which data file it is using?

UPDATE 2 Finally I gave up on the pg_ctl and did a:

sudo /etc/init.d/postgresql restart 9.2

.. as per the accepted answer.

I am developing a web application and I have a requirement to use LDAP for authentication / authorization purposes.

I have limited experience with LDAP and I would like to understand how one goes about defining models, or using existing models if any are established to store authorization information in an LDAP server. By looking at various LDAP servers it seems to me that although authentication is handled, more or less, in the same way, authorization is LDAP server-specific, and perhaps even application-specific.

For instance I've seen an Oracle Internet Directory model where groups are used to indicate roles and a group's users appeared as a multiple-value attribute in that group's (i.e. role's) entry. I've also seen models where the symmetric method is used in a Microsoft Active Directory installation, i.e. the groups and permissions a user belongs to are indicated as a multiple-value attribute in the user's entry. So my questions are:

[1] are there any established/prominent models on how to organize authorization information on an LDAP server?

[2] if such exist can I then rely on existing tools for managing roles, permissions and users? The idea being that I hand that tool over to the client's administrator without having to also develop a custom groups/roles/privilleges/users management front-end module myself.