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

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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
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