Postgress allow local connections uring trust.
for remote connections need to configure the pg_hba.conf to have entry like :


# TYPE  DATABASE    USER        CIDR-ADDRESS          METHOD

# IPv4 local connections:
host    all         all         127.0.0.1/32          md5
host    all        all          10.97.0.0/16          md5

To know more about CIDR address please visit http://en.wikipedia.org/wiki/Classless_Inter-Domain_Routing

taking backup:
c:\PostgresPlus\8.3\bin\pg_dump.exe -h localhost -p 5432 -U postgres -F p -v -f "C:\test.backup" "JA"

Installing and configuring in Linux

External Articles

Postgres Sever Configuration Tuning