Data location in PostgreSQL

Hi,
       I am using PostgreSQL7.3 in linux and i have
installed it in db/
folder into my account and also specified cluster area
as db/data at the
time of calling initdb.
       i want to take backup on another machine
whenever database
changes on primary server, then it should reflect on
backup server
also.but on the both machine (primary and backup)
directory structure
under /db/data/base is different.
       I want to know that how PostgrqSQL stores data
into file system
because both server had only one database which named
is nydb please let
me know that where data should be stored when i
defined cluster ara as
db/data and why different directory structure exist on
primary and
backup server even though they both have contains same
no. of tables and
same database and same contains of tables.
Thanks and regards,
Neelesh Vijaivargia.

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