I am quite new in Arch and a total beginner in PostgreSQL, so this may be a very basic question.
I installed postgresql 11.5-4 from extra and pgadmin 4 from AUR, both seem to be running well.
I created a test DB with the following command:
initdb -D /home/lg/test-db
I got the answer:
You can start the db-server using:
pg_ctl -D /home/lg/test-db -l logdatei start
I tried that and got:
pg_ctl -D /home/lg/test-db -l logdatei start
waiting for serer to start.... stopped
pg_ctl: could not start the server
check the log.
The log only says that the lockfile »/run/postgresql/.s.PGSQL.5432.lock« could not be created, because the folder could not be found. Under /run is no folder called "postgresql". I suppose postgresql can not create this folder, because it does not have the permission. Several posts online posts suggest to change the user/owner of the db to sudo, however. Postgresql prevents this, however. When I try any command as sudo, postgresql tells me that this command can't be run as root. There must be some very basic error in my thinking here, but I have not worked it out for 3 hours.
You'll have to remove /run/postgresql from unix_socket_directories in postgresql.conf before starting the server.
Probably You have /var/run symlinked to /run and run is on tmpfs. You should add something like d /run/postgresql 0755 postgres postgres - into /usr/lib/tmpfiles.d/postgresql.conf
I'm work with postgresql over large datasets and I move my database from the same HDD were is Ubuntu 18.04 installed to a other HDD.
I did the same process and move the data_directory to "Home" (which is at same HDD of the Ubuntu, but in other partition), in this location the postgresql works fine. The problem is I need a big space to upload my data (like 2 TB HDD) because that I try to move to another HDD, empty and formmated exclusive for the DB.
I follow to this tutorial Link of change Data Folder. Using the follow commands in Ubuntu terminal:
su postgres
/usr/lib/postgresql/10/bin/pg_ctl -D /media/path/postgresql/10/main -l logfile start
sudo systemctl stop postgresql
sudo systemctl status postgresql
sudo rsync -av /var/lib/postgresql /media/path/postgresql
sudo mv /var/lib/postgresql/10/main /var/lib/postgresql/10/main.bak
sudo gedit /etc/postgresql/10/main/postgresql.conf (change "data_directory")
sudo systemctl start postgresql
sudo systemctl status postgresql
In addition, I pass to the postgres the ownership of the folder as
chown -R postgres:postgres /media/path/postgresql/10/main
I write the modifications in "/path/postgresql.conf" to adjust to new data directory, reestart the server and I can't connect to server.
At terminal I get this message if I try to connect
"could not connect to server: No such file or directory Is the server running locally and accepting connections on Unix domain socket "/var/run/postgresql/.s.PGSQL.5432"?"
At Pgadmin client I get the problem is manifested as no connection.
In my case, rsync did not copied several files for some reason. May be they were not ready yet after the server stopped or something else.
After I made it once more next day, it started well:
sudo rsync -av /var/lib/postgresql/10/main.bak/ /media/disk1/postgres/postgresql/10/main/
Also try to check log for the actual reason:
tail -n 100 /var/log/postgresql/postgresql-10-main.log
At my case it was
postgres: could not find the database system
Expected to find it in the directory "/media/disk1/postgres/postgresql/10/main",
but could not open file "/media/disk1/postgres/postgresql/10/main/global/pg_control": No such file or directory
pg_ctl: could not start server
Examine the log output.
I have recently installed PostGIS on my Mac (El Capitan 10.11.4, Postgres is version 9.5.1) using Homebrew, and I am following these instructions - http://morphocode.com/how-to-install-postgis-on-mac-os-x/
When I try to start Postgres using
pg_ctl -D /usr/local/var/postgres start
I get the following error:
$ FATAL: lock file "postmaster.pid" already exists
HINT: Is another postmaster (PID 280) running in data directory "/usr/local/var/postgres"?
So I spent a few hours researching how to address this, but to no avail.
Notably, I tried to kill the PID as recommended in an answer on Superuser - https://superuser.com/questions/553045/fatal-lock-file-postmaster-pid-already-exists- (in the case above, I ran kill 208), but as soon as I tried to start Postgres again, I got the same error, albeit with a different PID number. I saw a few people recommended deleting the postmaster.pid file, but I feel like maybe I should save that as a last resort...
Admittedly part of the reason I'm not sure how to fix this is that I'm not really clear on what the postmaster even is - I'm just starting to learn about all of this.
Hopping into a Postgres database via the psql db_name command works just fine, for what it's worth.
Posting this in case it helps someone else:
I was having this same problem as the OP after a hard reboot when my laptop crashed. What helped me was running the following command to see what PID was associated with postmaster.pid:
cat /usr/local/var/postgres/postmaster.pid
The first number that appears will be the PID. Looking in Activity Monitor, I was able to see that Postgres was running, but without a PID number that matched the one shown.
Instead of the steps outlined in the answer referenced on Superuser, I restarted my laptop properly and then opened up Terminal and ran
brew services restart postgresql
This worked without having to remove postmaster.pid, which I saw a few other posts recommend. Sometimes it's the simple solutions that work.
I add here what worked for me, after a long time of searching:
Delete the postmaster.pid file:
rm /usr/local/var/postgres/postmaster.pid
Restart your postgres:
brew services restart postgresql
Hope this helps someone ...
Update 8/2022:
As Mike commented, for M1 Mac you would replace stage 1 with:
rm /opt/homebrew/var/postgresql/postmaster.pid
With M1 and specify Postgres Version # 14
rm -rf /opt/homebrew/var/postgresql#14/postmaster.pid
It often happens to me in OSx, when my system shutdown unexpectedly.
You can just remove the file postmaster.pid.
cd Library/Application Support/Postgres/var-{postgres-version}
and remove the postmaster.pid file
in case you use brew then your path should be something like:
/usr/local/var/postgres/postmaster.pid
restart the Postgres by using this command
pg_ctl -D /usr/local/var/postgres restart
Since you can connect to the database, you don't need to start the server again - it's already running.
pg_ctl is used to control the PostgreSQL server. Since your server is already started, your command:
pg_ctl -D /usr/local/var/postgres start
Returns an error, saying that there is a lock on postmaster.pid - which is true since there is already a server running under that PID.
There are two ways:
The most basic way - skip that step, your server is already running!
Executing a needless operation - stopping the server, and then starting it again.
You could stop your server doing :
pg_ctl -D /usr/local/var/postgres stop
So that you won't have the lock on postmaster anymore and you could use your command to start it again.
Postmaster is the main PostgreSQL process. You're trying to start PostgreSQL that's already running (and you're saying yourself you can connect to it). Just skip that step of your process.
When the system shutdown unexpectedly, my postgres crashs and i'm unable to connect to it.
What worked for me was:
1˚ Check postgres log:
tail -n 10000 /usr/local/var/log/postgres.log
2˚ Find the PID of postgress, should look like this:
FATAL: lock file "postmaster.pid" already exists
HINT: Is another postmaster (PID 707) running in data directory "/usr/local/var/postgres"?
3˚ Kill that process:
kill 707
4˚ Restart your postgres
brew services restart postgresql
After those steps i was able to connect to the database within my rails application.
If you got no important data to lose :
sudo killAll postgres
brew services restart postgresql
AGAIN : You could get data corrupted by doing this !
do it at your own risk !
I am using mac and these step work for me:-
step1: cd Library/Application\ Support/Postgres
(most commonly your Postgres installation will be located here)
step2: cd var-13
(if you are using version 12 then use cd var-12. Hope got the point)
step3: ls
(As you can see among the files you find the postmaster.pid, perfect.)
step4: rm postmaster.pid
When you have removed the stale postmaster.pid file you can restart PostgreSQL and everything should work as normal.
My OSX laptop had shutdown unexpectedly, and I was getting a stale postmaster.pid error in the PostgresApp. Shutting down my laptop and turning it back on again solved the problem.
After running the following commands
rm /usr/local/var/postgres/postmaster.pid
brew services restart postgresql
The error lock file "postmaster.pid" already exists comes up again.
When we run launchctl list | grep postgres
28618 0 homebrew.mxcl.postgresql
The existing file "postmaster.pid" was created by this daemon process hosted by launchctl.
We try to stop the homebrew.mxcl.postgresql through
sudo launchctl stop homebrew.mxcl.postgresql
launchctl disable homebrew.mxcl.postgresql
Unfortunately, none of them could stop the homebrew.mxcl.postgresql.
The reason is Disable and enable an agent using (persists between boots)
https://apple.stackexchange.com/questions/105892/disable-services-in-osx-services-msc
launchctl enable <name> or launchctl disable <name>
Two ways to solve it when the error lock file "postmaster.pid" already exists comes up again
In order to stop an agent immediately through
launchctl kill homebrew.mxcl.postgresql
Restart your desktop and run brew services start postgresql#14. Now, PostgreSQL could start successfully.
Hope it could help someone who met the same issue again.
This worked for me. First locate postmaster.pid (for me it was in the var directory as seen below, although it will be different on depending on your operating system). Then get rid of postmaster.pid, then kill the postgres process, then start/restart postgres service.
cd /var/lib/pgsql/data/
rm postmaster.pid
sudo pkill -u postgres
sudo systemctl start postgresql.service
If you have installed postgres with brew then simply run the following command and it will manage everything
brew services restart postgresql
I cannot "service postgresql start" by root:
Startup Log: /usr/bin/postmaster: error while loading shared
libraries: libz.so.1: failed to map segment from shared object:
Permission denied
I cannot "service postgresql start" by postgres:
Startup Log:runuser: cannot set groups: Operation not permitted
But I can start it by postgres user with command:
postmaster -D /usr/local/pgsql/data
Why?
When I installed, I used
initdb -D /usr/local/pgsql/data
not
service postgresql initdb
So I afterwards changed init.d/postgresql script with the new path. Is this causing problem?
Caused for me by creating the DB with
/etc/init.d/postgresql-9.3 initdb
Recreating with
service postgresql-9.3 initdb
solved the issue.
As Craig said this is either a file permission issue or a selinux issue. If it is a file permissions issu, that is easy enough to fix (give read/execute perms).
If it is an selinux issue your best option is to run audit2allow to identify the problem and ensure that selinux is configured to allow the correct access.
I receive error
FATAL: could not create lock file "postmaster.pid": Permission denied
when trying to execute command
pg_ctl restart --pgdata "D:\Program Files\PostgreSQL\8.3\data"
Full rights for postgres user to D:\, D:\Program Files\, D:\Program Files\PostgreSQL\ and D:\Program Files\PostgreSQL\8.3\data are set. What else I need to do?
I set full access to D:\Program Files\PostgreSQL\8.3\data to Users group and now it works. Detail are at
http://forumserver.twoplustwo.com/114/pokertracker/cant-connect-db-422617/
(last post).
You need to ensure that the user postgres has write permission to the postgres data_directory configured in postgresql.conf file. In my case /var/lib/postgresql/9.5/main/ if not add permission with:
chmod u+w /var/lib/postgresql/9.5/main/
You have to make ensure that the user postgres has right to write & execute /var/run/postgresql
sudo chmod 765 /var/run/postgresql
sudo chown postgres /var/run/postgresql
I had this issue due to installing postgres-xc and the solution was to remove it.
pg_ctl is the most common (and recommended) way used to start/stop/etc postgres.
For some reason it was not part of my postgres install.
After duckduckgo'ing a little, I installed postgre-xc which includes pg_ctl.
postgres-xc changed the owner of /var/run/postgresql from postgres to postgres-xc.
This caused lots of headaches and warnings about being unable to lock the pid file.
So, I removed postgres-xc (and reverted the owner of /var/run/postgresql to postgres).
Instead of using pg_ctl, I control postgres using
service postgresql status
or
/etc/init.d/postgresql status.
Hopefully this will help someone.
postgresql serviceis logined in NETWORK SERVICE, so you must needed make data dir(ie: "D:\Program Files\PostgreSQL\8.3\data") is full control over to NETWORK SERVICE group.
I just added my username to group "postgres"; all went fine
sudo adduser your-user-name postgres
Ciao