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AlannY wrote:
> Hi there.
>
> I'm using PostgreSQL as my main database engine. Everything works.
>
> I have one server for PostgreSQL, and space on it are lowing down.
>
> I want to buy a new server and somehow connect it with first one, that
> PostgreSQL will use this new server's HDD. I don't want to buy new HDD
> for the first server, because I don't have a space in server box.
>

For the requirements you've given above, buy an external storage array
instead of a new server  put a SAS card in your server, and a SAS/SATA
bay as large as you need for additional disks.    once these additional
disks are formatted and mounted as a file system, which I'm going to
call /u00 here, I'd do something like...

    1) shut down postgres
    2) mv /var/lib/pgsql/data /u00/pgdata
    3) ln -s /u00/pgdata /var/lib/pgsql
    4) restart postgres

and poof, LOTS of space.

example such enclosure, this one holds 12 3.5" SAS/SATA drives in a 2U
chassis, and is strictly something I googled, I have no experience with
the vendor or OEM
http://www.aicipc.com/ProductDetail.aspx?ref=XJ1100%20series%20-%202U%2012-bay
I would format a unit like this as raid10 using your OS's native raid
(mdadm on linux, zpool on solaris, etc).

for the SAS card, I'd lean towards a LSI Logic, such as
http://www.lsi.com/storage_home/products_home/host_bus_adapters/sas_hbas/external/sas9200-8e/index.html