Incorrect checksum during recovery PostgreSQL database (32bits) from a backup on Mac Os X 64 bits

When I try to recover PostgreSQL database from a backup saved under my old version of Mac Os X 10.5 (32bits) on my new version 10.6 (64bits), I have this error :

# sudo -u postgres /opt/local/lib/postgresql82/bin/postgres -D defaultdb_backup
FATAL:  incorrect checksum in control file

This was due to the one server running a 32 bit version and the other one running a 64 bit.

How do I recover my old data ?

From serverfault Kevin Campion

• Install somewhere postgres in exactly the same version as before, on same architecture, compiles with the same options, then you can recover. doing backups by writing wal segments and/or copying data directory is not really portable.

  Kevin Campion : I can't install on the same architecture... I've not other alternative ?

  depesz : yes. load data from pg_dump output. otherwise you're hosed. what made you make a backup of files in their binary, architecture-and-compile-options-dependent format?
  From depesz

• As depesz said you will need to compile a 32bit version of Postgres to import the backup. You should be able to get the installer from the Postgres website and run the 32 bit version temporarily, even on a 64bit install of OS X.

  As an aside, in the future when doing backups I MUCH prefer using pg_dump --clean to get a full dump from the database. You can use a pg_dump --clean file on any version of postgres.

  From Josh Budde

• I found how to recover my datas.

  The postgresql executable is in 64 bits :

  # file /opt/local/lib/postgresql82/bin/postgres
  /opt/local/lib/postgresql82/bin/postgres: Mach-O 64-bit executable x86_64
  

  I verify the postgresql executable in my backup is in 32 bits :

  # file /Volumes/Backup/Backups.backupdb/MyMacBook/2009-09-23-004611/Macintosh\ HD/opt/local/lib/postgresql82/bin/postgres
  /Volumes/Backup/Backups.backupdb/MyMacBook/2009-09-23-004611/Macintosh HD/opt/local/lib/postgresql82/bin/postgres: Mach-O executable i386
  

  I copy it on my system :

  # sudo cp /Volumes/Backup/Backups.backupdb/MyMacBook/2009-09-23-004611/Macintosh\ HD/opt/local/lib/postgresql82/bin/postgres /opt/local/lib/postgresql82/bin/postgres_32
  

  And now when I do :

  # sudo -u postgres /opt/local/lib/postgresql82/bin/postgres_32 -D defaultdb_backup
  

  It works !

  Thank you all

  From Kevin Campion