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After upgrading my MacMini home server from OS-X 10.7 (Lion) Server to OS-X 10.8 (ML) +, I saw PostgreSQL 9.1.4 was released.

Unfortunately, the setup process for PostgreSQL 9.1.4 has created these brand new databases: collab, webauth, postgres, tempalte0, template1; all the other databases and roles created by me seem to have been deleted!

To better understand what has happened:

> Which postgres

OSX 10.7.4: /usr/bin/postgres
OSX 10.8: /Applications/

$PGDATA is now on:

OSX 10.7.4: "/var/pgsql"
OSX 10.8 "/Library/Server/PostgreSQL/Data"

After the update the /var/pgsql folder is gone.

Since I do not want to repeat this experience in future updates, I think it is a good idea to create my database on a separate cluster/instance.

How would advise me from here?

  • Is there any other way to avoid losing my databases?
  • Where and how should I create my own databases without interfering with Apple's databases?
  • How can I configure and start a second instance of PostgreSQL on the same OS-X server?
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Is it at all remotely possible that you have two instances running? – swasheck Aug 6 '12 at 13:22
@swasheck definitely, only one instance running, checked by: ps -ef | grep postgress – Franco Rondini Aug 7 '12 at 10:16
up vote 1 down vote accepted
"all others databases and roles created by my own are lost!"

I can't speak to the best practices for creating a new database, but as part of the Mountain Lion Server upgrade all of the "old" Postgres data should have been backed up to a subdirectory under /Library(/Server?) Unfortunately as soon as I discovered this I moved-and-renamed the directory for safekeeping so I don't have the exact name!

I have a completely separate install of Postgres that I built myself for webapp purposes, but I certainly wouldn't call what my approach a "best practice". Largely what I did was build a "stock" install using a very similar set of configure parameters as Apple did (discovered by running pg_config) but with a different install location and default port setting. Following that I coptied-and-tweaked /Applications/ and that's worked fine for me so far.

share|improve this answer
Thanks you for the support, /Library/Server/Previous it's a very usefull hint, for example I found the old plists in /Library/Server/Previous/System/Library/LaunchDaemons and the old PGDATA in /Library/Server/Previous/private/var/pgsql/. Shame Library/Server/Previous/Library/Server/PostgresSQL/Backup is empty (btw: I had not activated TimeMachine). Now I'm wondering that maybe it would be possible to restart, even the old instance (9.0.4) possibly on another port. – Franco Rondini Aug 7 '12 at 10:34
The idea of having a completely separate install of Postgres I think it's great, nevertheless a checklist or link to some pretty good story that explains how to do it step by step would be very welcome. The problem primarily is: how to determine which path on filesystem to use to be sure that the next system updates do not impact on our instance. – Franco Rondini Aug 7 '12 at 10:48

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