Is the server running on host "localhost" (::1) and accepting TCP/IP connections on port 5432?

Question

Before anything, please note that I have found several similar questions on Stack Overflow and articles all over the web, but none of those helped me fix my issue:

• PG Error could not connect to server: Connection refused Is the server running on port 5432?
• PG::ConnectionBad - could not connect to server: Connection refused
• psql: could not connect to server: Connection refused

Now, here is the issue:

• I have a Rails app that works like a charm.
• With my collaborator, we use GitHub to work together.
• We have a master and an mvp branches.
• I recently updated my git version with Homebrew (Mac).
• We use Foreman to start our app locally.

Now, when I try to launch the app locally, I get the following error:

PG::ConnectionBad at / could not connect to server: Connection refused     Is the server running on host "localhost" (::1) and accepting     TCP/IP connections on port 5432? could not connect to server: Connection refused     Is the server running on host "localhost" (127.0.0.1) and accepting     TCP/IP connections on port 5432? 

I tried to reboot my computers several times.

I also checked the content of /usr/local/var/postgres:

PG_VERSION      pg_dynshmem     pg_multixact    pg_snapshots    pg_tblspc       postgresql.conf base            pg_hba.conf     pg_notify       pg_stat         pg_twophase     postmaster.opts global          pg_ident.conf   pg_replslot     pg_stat_tmp     pg_xlog         server.log pg_clog         pg_logical      pg_serial       pg_subtrans     postgresql.auto.conf 

As you can see, there is no postmaster.pid file in there.

Any idea how I could fix this?

Answer 1

run postgres -D /usr/local/var/postgres and you should see something like:

 FATAL:  lock file "postmaster.pid" already exists  HINT:   Is another postmaster (PID 379) running in data directory "/usr/local/var/postgres"? 

Then run kill -9 PID in HINT

And you should be good to go.

Answer 2

You most likely ran out of battery and your postgresql server didn't shutdown correctly.

The easiest workaround is to download the official postgresql app and launch it: it will force the server to start (http://postgresapp.com/)