Обсуждение: Moving database cluster
An Ubuntu install creates a postgres cluster automatically on /var/lib/postgresql/8.4/main Whats the best procedure for moving this cluster to an other location? Should I just rerun initdb? What happens then with the default cluster or how could I delete it? Thanks, Fernando.
Le 14/01/2010 21:40, Fernando Hevia a écrit : > > An Ubuntu install creates a postgres cluster automatically on > /var/lib/postgresql/8.4/main > Whats the best procedure for moving this cluster to an other location? > Should I just rerun initdb? What happens then with the default cluster or > how could I delete it? > If you don't have any data on it, the best way is to drop it with pg_dropcluster, and create a new one with pg_createcluster. -- Guillaume. http://www.postgresqlfr.org http://dalibo.com
On Thursday 14 January 2010, Fernando Hevia elucidated thus: > An Ubuntu install creates a postgres cluster automatically on > /var/lib/postgresql/8.4/main > Whats the best procedure for moving this cluster to an other > location? Should I just rerun initdb? What happens then with the > default cluster or how could I delete it? The easiest way is to shut down Pg, move the 'main' directory somewhere else, and then point a symlink to the new location. j -- Joshua Kugler Part-Time System Admin/Programmer http://www.eeinternet.com PGP Key: http://pgp.mit.edu/ ID 0x14EA086E
> -----Mensaje original----- > De: Guillaume Lelarge [mailto:guillaume@lelarge.info] > > Le 14/01/2010 21:40, Fernando Hevia a écrit : > > > > An Ubuntu install creates a postgres cluster automatically on > > /var/lib/postgresql/8.4/main Whats the best procedure for > moving this > > cluster to an other location? > > Should I just rerun initdb? What happens then with the > default cluster > > or how could I delete it? > > > > If you don't have any data on it, the best way is to drop it > with pg_dropcluster, and create a new one with pg_createcluster. > > Sound advice. Thanks!!
> -----Mensaje original----- > De: > > On Thursday 14 January 2010, Fernando Hevia elucidated thus: > > An Ubuntu install creates a postgres cluster automatically on > > /var/lib/postgresql/8.4/main Whats the best procedure for > moving this > > cluster to an other location? Should I just rerun initdb? > What happens > > then with the default cluster or how could I delete it? > > The easiest way is to shut down Pg, move the 'main' directory > somewhere else, and then point a symlink to the new location. > Thanks for your reply. I had considered this first but then I wasn't sure if there would be any performance penalty. The current main directory sits on a 'slow' RAID 1 volume while the new one will sit on a 'fast' 12 disk RAID 10 volume. I guess the symlink shouldn't be troublesome but I don't know if some PG process will continually be reading this link encumbering somehow the RAID 1 disks. Regards, Fernando.
On Thursday 14 January 2010, Fernando Hevia elucidated thus: > > The easiest way is to shut down Pg, move the 'main' directory > > somewhere else, and then point a symlink to the new location. > > Thanks for your reply. > I had considered this first but then I wasn't sure if there would be > any performance penalty. > The current main directory sits on a 'slow' RAID 1 volume while the > new one will sit on a 'fast' 12 disk RAID 10 volume. > I guess the symlink shouldn't be troublesome but I don't know if some > PG process will continually be reading this link encumbering somehow > the RAID 1 disks. I'm not sure how Pg does it, but I remember reading several years ago that MySQL would, upon startup, "resolve" the symlink, and use the real path name for the rest of its execution. I would assume Pg does something similar. j -- Joshua Kugler Part-Time System Admin/Programmer http://www.eeinternet.com PGP Key: http://pgp.mit.edu/ ID 0x14EA086E
On Thu, Jan 14, 2010 at 06:21:14PM -0300, Fernando Hevia wrote: - - - > -----Mensaje original----- - > De: Guillaume Lelarge [mailto:guillaume@lelarge.info] - > - > Le 14/01/2010 21:40, Fernando Hevia a écrit : - > > - > > An Ubuntu install creates a postgres cluster automatically on - > > /var/lib/postgresql/8.4/main Whats the best procedure for - > moving this - > > cluster to an other location? - > > Should I just rerun initdb? What happens then with the - > default cluster - > > or how could I delete it? - > > - > - > If you don't have any data on it, the best way is to drop it - > with pg_dropcluster, and create a new one with pg_createcluster. - > - > - - Sound advice. Thanks!! in SLES, assuming you have no data in the DB, I'd go to /etc/sysconfig/postgresql modify POSTGRES_DATADIR="/my/new/path" and then (logout/log back in to get your PGDATA set correctly and ) initdb No need to mess with symlinks. I'm sure ubuntu has something similar to sysconfig Dave