Re: installing multiple databases on one host

Remigiusz Boguszewicz <zebra640_at_poczta.onet.pl> wrote:

> Other Pros I have noticed:
> + I can temporary disable selected database from outside world by
> removing tnsnames.ora, which is impossible with scenario 1.

It's not a valid argument. You can use the TNS_ADMIN variable if you want to have several tnsnames.ora

> + More and more I like the idea of many users, with man .profile files

I don't think it's a valid argument. You should install the Oracle binaries with a dedicated user (used only for the install). And you should this user only for the installation of patch. So having several .profiles files is, IMHO, useless.

> Cons:
> - I still do not know if I need a common dba group. At first I have
> tried with different one but to no avail. (I got "ORA-01031:
> insufficient privileges" after sqlplus "/ as sysdba")

You choose the group which will give you the "privilege" when you install the binaries. If you have several installation, you can have several dba group.

And I think that's the main Pro for having several installation : Each instance will use a different user for running the background processes. As the oracle binary has a setuid bit, the user executing the database processes is the user used for the installation of the binaries (and not the one which has launched the database). So the database will be completely independant each other. Having different user will allow to identify easily which database use which resource. Instead of having several shared memory owned by only one user (and not being able to know which instance own which shared memory segment), you will immediately know, by the owner of the segment, the associated instance.

So, if you have enough disk (for the several binaries installation) and enough RAM (the processes will not share readonly memory segment between the instance), so yes, I think it can be a good idea to have several binaries. Received on Thu Sep 30 2004 - 14:14:53 CDT