Обсуждение: connect postgresql to a different cluster
Hi, My question refers to a newly installed postgresql 9.4 on ubuntu 15.04. Is it possible to mount a file system with an existing 9.4 version postgresql cluster onto a new machine and get a fresh postgresql install to connect to that cluster? When I installed postgresql it created a /var/lib/postgrersql/9.4/main cluster, and pointed to it via /etc/postgresql/9.4/main I then mounted a HD with an existing v9.4 postgresql cluster called gisdata at /mnt/geo_pgsql/postgres. Note that I have no /etc/postgresql/9.4/gisdata directory. (I forgot to back it up before reinstalling ubuntu) initdb -D /mnt/geo_pgsql/postgres will clobber my existing gisdata cluster, will it not? So is there a way to move a cluster to another (same version) postgreql installation? Just for giggles I tried copying the /etc/postgresql/9.4/main folder to /etc/postgresql/9.4/gisdata and hacking the contents therein, but that never worked. Googling around and reading installation guides only comes up with creating new clusters. I doubt if setting the PGDATA variable (where is that set???) will help as the /etc/postgresql/9.4/gisdata is missing. A thought is to change the name of this cluster to xxx, create the cluster again, delete it and mv xxx back to this name. But maybe there is an elegant way to "import" a cluster? TIA, Zoltan -- =========================================== Zoltan Szecsei PrGISc [PGP0031] Geograph (Pty) Ltd. GIS and Photogrammetric Services P.O. Box 7, Muizenberg 7950, South Africa. Mobile: +27-83-6004028 Fax: +27-86-6115323 www.geograph.co.za ===========================================
But maybe there is an elegant way to "import" a cluster?
It should possible to accomplish your goal without performing "initdb" - though you may find it easier to forgo the Ubuntu utilities and just write the necessary pg_ctl commands yourself. You indeed need to use either "$PGDATA" or explicit command line parameters and just point directly at the cluster data directory that you mounted - with pg_ctl, not initdb.
Whether that is easier than a simple pg_dump/pg_restore "import" it up for you to decide.
You might be able to rename things to match the expected structure for the Ubuntu cluster commands.
David J.
> > Hi, > My question refers to a newly installed postgresql 9.4 on ubuntu 15.04. > > Is it possible to mount a file system with an existing 9.4 version > postgresql cluster onto a new machine and get a fresh postgresql install > to connect to that cluster? > > When I installed postgresql it created a /var/lib/postgrersql/9.4/main > cluster, and pointed to it via /etc/postgresql/9.4/main > > I then mounted a HD with an existing v9.4 postgresql cluster called > gisdata at /mnt/geo_pgsql/postgres. > Note that I have no /etc/postgresql/9.4/gisdata directory. (I forgot to > back it up before reinstalling ubuntu) > > initdb -D /mnt/geo_pgsql/postgres will clobber my existing gisdata > cluster, will it not? Use: pg_ctl -D /mnt/geo_pgsql/postgres -l /tmp/logfile start Saludos, Gilberto Castillo ETECSA, La Habana, Cuba --- This message was processed by Kaspersky Mail Gateway 5.6.28/RELEASE running at host imx3.etecsa.cu Visit our web-site: <http://www.kaspersky.com>, <http://www.viruslist.com>
Hi,
Thanks to David and Gilberto for the input.
All sorted and working.
Kind regards,
Zoltan
On 2015/05/07 20:02, Gilberto Castillo wrote:
Thanks to David and Gilberto for the input.
All sorted and working.
Kind regards,
Zoltan
On 2015/05/07 20:02, Gilberto Castillo wrote:
Hi, My question refers to a newly installed postgresql 9.4 on ubuntu 15.04. Is it possible to mount a file system with an existing 9.4 version postgresql cluster onto a new machine and get a fresh postgresql install to connect to that cluster? When I installed postgresql it created a /var/lib/postgrersql/9.4/main cluster, and pointed to it via /etc/postgresql/9.4/main I then mounted a HD with an existing v9.4 postgresql cluster called gisdata at /mnt/geo_pgsql/postgres. Note that I have no /etc/postgresql/9.4/gisdata directory. (I forgot to back it up before reinstalling ubuntu) initdb -D /mnt/geo_pgsql/postgres will clobber my existing gisdata cluster, will it not?Use: pg_ctl -D /mnt/geo_pgsql/postgres -l /tmp/logfile start Saludos, Gilberto Castillo ETECSA, La Habana, Cuba--- This message was processed by Kaspersky Mail Gateway 5.6.28/RELEASE running at host imx3.etecsa.cu Visit our web-site: <http://www.kaspersky.com>, <http://www.viruslist.com>
-- =========================================== Zoltan Szecsei PrGISc [PGP0031] Geograph (Pty) Ltd. GIS and Photogrammetric Services P.O. Box 7, Muizenberg 7950, South Africa. Mobile: +27-83-6004028 Fax: +27-86-6115323 www.geograph.co.za ===========================================