Dumping data using pg_dump after chrooting to a different partition

Krishnamurthy Radhakrishnan <kradhak@xxxxxxxxx> · Mon, 24 Oct 2011 16:10:27 -0600



    Hi,

    
    I am new to PostgreSQL. We are using PostgreSQL 9.0.2 on our linux
    server. We have an instance of PostgreSQL 9.0 running using the
    primary partition on the server.

    
    We want to use the pg_dump and psql programs to migrate the data
    during our software upgrade process. For upgrade, we plan to do the
    following:

    
      chroot to a secondary partition on the server.
      install the software RPMs including PostgreSQL RPMs
      start a secondary instance of PostgreSQL DB server using a
        different port and data directory.
      run pg_dump to dump the data from the primary instance to a
        file.
      run psql to import the data from the file into the secondary
        instance.
    
    However when I tried to perform the pg_dump as mentioned above, I
    get the following error:

    pg_dump: [archiver (db)] connection to database "TestDB" failed:
    could not connect to server: No such file or
    directory|<LVL::Debug>

    Is the server running locally and accepting|<LVL::Debug>

    connections on Unix domain socket
    "/tmp/.s.PGSQL.5432"?|<LVL::Debug>

    
    pg_dump works before chrooting to the secondary partition. Can you
    please provide a way to dump the data after chrooting?

    
    Thanks for your help.

    
    Radha