Postgres DB not starting on Mac OSX: ERROR says: connections on Unix domain socket [closed]

Solution 1:

I had the same problem today on Mac Sierra. In Mac Sierra you can find postmaster.pid inside /Users/<user_name>/Library/Application Support/Postgres/var-9.6. Delete postmaster.pid and problem will be fixed.

Solution 2:

This can happen if the database did not shut down correctly. To fix it simply delete the postmaster.pid file. The location differs based on your OS:

MacOS:

 rm /Users/<user_name>/Library/Application\ Support/Postgres/var-9.6/postmaster.pid

or using Postgres.app:

 rm /Users/<user>/Library/Application\ Support/Postgres/var-10/postmaster.pid

Linux:

 rm /usr/local/var/postgres/postmaster.pid

Solution 3:

I have the database working now.

Here are the steps I took:

1. I rebooted my computer
2. I opened the terminal and ran cd /
3. Then I did ls -la
4. Ensured that I could get to MackintoshHD/usr/local/var/postgres
5. Then did ls -la
6. Here I saw the postmaster.pid file
7. I ran this command cp postmaster.pid ~/Desktop which copied the file to my desktop.I like to do this if I am deleting files. If something does wrong i can put it back
8. Then I ran this command to remove the file from the postgres directory rm -r postmaster.pid
9. I went to my pgadmin3 gui and fired it up. and Voila it worked :)

Thanks to @Craig Ringer for his help

Solution 4:

I'm using Postgres.app, and the below worked for me:

I entered the commands into my terminal below, locating the Postgres folder beforehand and not using "justin".

$declare -x PGDATA="/Users/justin/Library/Application Support/Postgres/var-9.4"

$pg_ctl restart -m immediate

As Justin explains in his post, the output after this was:

waiting for server to shut down……………………………………………………… failed pg_ctl: server does not shut down

After entering the command again:

$pg_ctl restart -m immediate

It worked and I got this message:

pg_ctl: old server process (PID: 373) seems to be gone starting server anyway server starting LOG: database system was interrupted; last known up at 2015-07-28 18:15:26 PDT LOG: database system was not properly shut down; automatic recovery in progress LOG: record with zero length at 0/4F0F7A8 LOG: redo is not required LOG: database system is ready to accept connections LOG: autovacuum launcher started

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