Before converting the data and updating the server, a PostgreSQL
server should be installed on the machine the pnfs server is
running on. In principle it is possible to run it on a separate
server, however, this will most likely result in degraded
performance and is not supported by this documentation. pnfs
might also use the same database server as other components of
the dCache instance. For a discussion of the usages of
PostgreSQL by dCache and its configuration see Chapter 23, PostgreSQL and dCache.
Warning
Please make sure that while doing the actual conversion as described below, the pnfs service it not active. So, shut it down first.
Prepare the PostgreSQL server by creating a database user for
the pnfs server. It has to have permissions to create
databases. We suggest to call it pnfsserver:
[root] #su - postgres[user] $createuser --no-adduser --createdb pnfsserver
Or use
[root] #su - postgres[user] $createuser --no-adduser --createdb --pwprompt pnfsserver
to set a password if PostgreSQL is configured more securely as described in Chapter 23, PostgreSQL and dCache.
The following procedure requires a downtime of the pnfs
server and therefore of the dCache system.