如何获得Postgres服务器以创建并关闭？

Question

I have an instance of a Postgres server running that I've started with the command:

pg_ctl -D /usr/local/var/postgres/data -l /usr/local/var/postgres/data/server.log start

Running the command createdb test prompts me for my password twice, then I get this error:

createdb: could not connect to database template1: FATAL:  password authentication failed for user "joey" 

Also, when I try to stop the server using

pg_ctl -D /usr/local/var/postgres/data stop -m smart

I get this error message:

pg_ctl: PID file "/usr/local/var/postgres/data/postmaster.pid" does not exist
Is server running?

Is there something I'm missing or forgot to initialize/install? I used these instructions to install.

I checked this answer and this answer and neither of the two fixed my problem.

Answer 1

From the log file you added in your comment, it looks as if either there is another postgresql instance running on the machine (or possibly something else which is using the same port as postgresql wants to use):

LOG:  could not bind IPv6 socket: Address already in use
HINT:  Is another postmaster already running on port 5432? If not, wait a few seconds and retry.
LOG:  could not bind IPv4 socket: Address already in use
HINT:  Is another postmaster already running on port 5432? If not, wait a few seconds and retry.
LOG:  could not bind IPv6 socket: Address already in use
HINT:  Is another postmaster already running on port 5432? If not, wait a few seconds and retry.
WARNING:  could not create listen socket for "localhost"
FATAL:  could not create any TCP/IP sockets

This is stopping the database from starting up to begin with.

To see what process that could be, you can use lsof:

$ sudo lsof | grep -i listen
...
postmaste 19732  postgres    3u     IPv6            1194355       0t0        TCP localhost:postgres (LISTEN)
postmaste 19732  postgres    4u     IPv4            1194356       0t0        TCP localhost:postgres (LISTEN)
...

In the above sample, from a Linux host, you can see that a process called postmaster (it is truncated in the printout) listens on localhost:postgres, meaning the localhost address port 5432 (lsof is translating the port 5432 into 'postgres' via the file /etc/services which contains a mapping between well known port numbers and corresponding services).

The fact that createdb is prompting for your password implies that it is connecting to a database somewhere, although I could not spot it the ps printout you sent.

The other part of your question was why createdb could not connect to your database (or whatever database is running on your machine). If it is a freshly created database cluster then it will not have any users defined other than the default 'postgres' user. You must issue commands with this user:

createdb -U postgres test

Without the -U option it will try to connect using your current login user, which won't exist in the database.

It might also be that you will need to authenticate as the postgres user. The file pg_hba.conf in the postgresql data directory controls what kind of authentication will be needed.

In general the postgresql documentation is excellent; I suggest you read through the section Server Setup and Operation to check that you have a valid configuration.