I've just installed Postgressql (9.5.4 vc14_0) and Psycopg2 (2.7.5 py36h74b6da3_0) and I'm trying to use them within my Anaconda environment on Windows 10.
Whenever I run psycopg2.connect("host=localhost user=postgres") in a python interpreter or just psql on the command line I get this error:
could not connect to server: Connection refused (0x0000274D/10061) Is the server running on host "localhost" (127.0.0.1) and accepting TCP/IP connections on port 5432?
I've looked at other Stackoverflow questions regarding this, some answers say to look into a pg_hba.conf file although I haven't be able to find any. Where can I find a pg_hba.conf file for my Postgresql in my Anaconda Environment for Windows? If I have to make one, what should go in it? I haven't seen another SO question that uses the same Postgresql-Anaconda-Windows setup that I'm using.
Also I've looked into services.msc but haven't seen a service regarding postgresql.
I just ran into this error as well. Similar to what you did, I followed the installation page, ran conda install -c anaconda postgresql and received the same error in your post.
I have used postgresql through direct installation before, in osx and as far as I can recall, you could just psql into the database once the installation is complete.
Maybe this isn't the case for anaconda installations. I overcame this by initializing a new database system in a new, empty folder. In my case, I created a new folder in "\AppData\Local\conda\"
-- Initialize the database system
pg_ctl init -D <path_to_your_database_system>
-- Start the database
C:/Users/kerwei/AppData/Local/Continuum/anaconda3/envs/py36/Library/bin/pg_ctl -D <path_to_your_database_system> -l logfile start
NOTE: After playing around with for awhile, I realized that once you exit the conda environment, the database instance gets terminated too - without properly shutting down. As I don't use it for production stuffs, it doesn't really bother me. However, further steps can be taken to include the database booting and shutting down during conda activate or conda deactivate to make it less cumbersome.
I am attempting to start a Postgres SQL server on amazon Linux using the command
sudo service postgresql start
I installed the server using this method. I have added it here for simplicity
sudo rpm -i https://download.postgresql.org/pub/repos/yum/9.6/redhat/rhel-6-x86_64/pgdg-ami201503-96-9.6-2.noarch.rpm
and then
sudo yum install postgresql96-server.x86_64
after which i did this to install the command line tools for postgres
sudo yum install postgresql96.x86_64 postgresql96-libs.x86_64
Any suggestions on how I can start the server ? I usually start the server using
the command
sudo service postgresql start
however its not working in this case as it says "Unrecognized service"
I then tried this
postgres -D /usr/local/pgsql/data
postgres: could not access directory "/usr/local/pgsql/data": No such file or directory. Run initdb or pg_basebackup to initialize a PostgreSQL data directory.
Having the same issue, or similar. May be I installed pgsql from source, don't remember. We could make our own service start files. How? Let's find out! >>RTFM<< starting with what we already know:
man service
which leads us to chkconfig(8), so
man chkconfig
and it gives us an option
chkconfig --add ${svcname}
to add a brand new service under a name we choose!
But before we do, we might actually want to check what's already there. With
service --status-all
we get a list of all known services and their run status. And I found "postmaster" in my list, and as you might know, the PostgreSQL master server to connect to used to be called "postmaster". Yet, when I try
service postmaster status
it also tells me it doesn't know such service. OK, forget it -- for now -- just let's move on with making our own! But I still want to peek what there is in run-level 3 (normal server run level). So I go
ls -1 /etc/rc.d/rc3.d |fgrep post
and there I find: "K36postgresql95"! So, accordingly our service name should be "postgresql95". Trying that:
service postgresql95 status
it says now "postmaster is stopped". Confusingly the name the service reports for itself both in service --status-all and when we individually inquire for it is different than the name used to actually address it in the service command. Good to know. Easy enough to search /etc/rc.d for the name of interest.
service postgresql95 start
now starts the service. And check with
psql -U ${pguser} ${pgdb}
and I find that working. So now all I need to do is enable that service at system boot to auto-start
chkconfig --levels 3 postgresql95 on
and that works, doesn't it?
PS: It doesn't matter that I happen to run version 9.5
I recently installed PostgreSQL 9.2.24 on Amazon Linux 2 and I had to initialize the database manually before being able to create ROLE and DATABASE as I normally would on Ubuntu.
// initialize database after installing with yum
$ sudo postgresql-setup initdb
// start
$ sudo systemctl start postgresql.service
I am trying to use postgres on my machine and realized that some time ago I had installed the database software after running brew install postgres and receiving Error: postgresql-9.4.5_2 already installed. From there I decided to install homebrew/services to be able to run postgres in the background and successfully launched and closed the background job with
brew services start postgresql==> Successfully startedpostgresql(label: homebrew.mxcl.postgresql)
However, when I run postgres I received the error of:
postgres does not know where to find the server configuration file.
You must specify the --config-file or -D invocation option or set the PGDATA environment variable.
When I followed an answer on SO, cat /usr/local/var/postgres/server.log I received the following error:
LOG: skipping missing configuration file "/usr/local/var/postgres/postgresql.auto.conf"
FATAL: database files are incompatible with server
DETAIL: The data directory was initialized by PostgreSQL version 9.3, which is not compatible with this version 9.4.5.
Which makes me think that I had an older version of PostgreSQL installed that needs to be removed.
I then tried psql and received:
psql: could not connect to server: No such file or directory
Is the server running locally and accepting
connections on Unix domain socket "/tmp/.s.PGSQL.5432"?
And finally decided to init a new db with initdb /usr/local/var/postgres, but that didn't fix it, which resulted in following the original message and setting an env varible: export PGDATA=/usr/local/var/postgres. After trying postgres again, I receive
LOG: skipping missing configuration file "/usr/local/var/postgres/postgresql.auto.conf"
FATAL: database files are incompatible with server
DETAIL: The data directory was initialized by PostgreSQL version 9.3, which is not compatible with this version 9.4.5.
What this tells me is that there is clearly a version compatibility issue, which needs to be resolved in order to launch my postgres server, but I'm not sure what file paths need to be cleared or the proper way to clear them. Can anyone provide some guidance?
I had the same problem and I got it to work by running:
pg_ctl -D /usr/local/var/postgres start && brew services start postgresql
(this guide was good).
I'm trying to run psql on my Vagrant machine, but I get this error:
psql: 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"?
Note: Vagrant 1.9.2
Box: ubuntu/trusty64, https://atlas.hashicorp.com/ubuntu/boxes/trusty64
EDIT
Commands I've used in order to install and run postgres:
sudo apt-get update
sudo apt-get install postgresql
sudo su postgres
psql -d postgres -U postgres
I've had this same issue, related to the configuration of my pg_hba.conf file (located in /etc/postgresql/9.6/main). Please note that 9.6 is the postgresql version I am using.
The error itself is related to a misconfiguration of postgresql, which causes the server to crash before it starts.
I would suggest following these instructions:
Certify that postgresql service is running, using sudo service postgresql start
Run pg_lsclusters from your terminal
Check what is the cluster you are running, the output should be something like:
Version - Cluster Port Status Owner Data directory
9.6 ------- main -- 5432 online postgres /var/lib/postgresql/9.6/main
Disregard the '---' signs, as they are being used there only for alignment.
The important information are the version and the cluster. You can also check whether the server is running or not in the status column.
Copy the info from the version and the cluster, and use like so:
pg_ctlcluster <version> <cluster> start, so in my case, using version 9.6 and cluster 'main', it would be pg_ctlcluster 9.6 main start
If something is wrong, then postgresql will generate a log, that can be accessed on /var/log/postgresql/postgresql-<version>-main.log, so in my case, the full command would be sudo nano /var/log/postgresql/postgresql-9.6-main.log.
The output should show what is the error.
2017-07-13 16:53:04 BRT [32176-1] LOG: invalid authentication method "all"
2017-07-13 16:53:04 BRT [32176-2] CONTEXT: line 90 of configuration file "/etc/postgresql/9.5/main/pg_hba.conf"
2017-07-13 16:53:04 BRT [32176-3] FATAL: could not load pg_hba.conf
Fix the errors and restart postgresql service through sudo service postgresql restart and it should be fine.
I have searched a lot to find this, credit goes to this post.
Best of luck!
I had the same issue but non of the answers here helped.
How I fixed it (mac)
Try to start postgresql with pg_ctl -D /usr/local/var/postgres start
Look for the Error Message that says something like FATAL: could not open directory "pg_tblspc": No such file or directory.
Create that missing directory mkdir /usr/local/var/postgres/pg_tblspc
Repeat from step one until you created all missing directories
When done and then trying to start postgresql again it might say FATAL: lock file "postmaster.pid" already exists
Delete postmaster.pid: rm /usr/local/var/postgres/postmaster.pid
Start postgres with: pg_ctl -D /usr/local/var/postgres start
Done ✨
These two steps solved it for me on Mac:
rm /usr/local/var/postgres/postmaster.pid
brew services restart postgresql
For M1 Macs:
rm /opt/homebrew/var/postgres/postmaster.pid
brew services restart postgresql
In case you face this issue (reported by #luckyguy73): psql: FATAL: database "postgresql" does not exist
You can run
brew postgresql-upgrade-database
to fix it.
I am just posting this for anyone who is feeling lost and hopeless as I did when I found this question. It seems that sometimes by editing some psotgresql-related config files, one can accidentally change the permissions of the file:
Note how pg_hba.conf belongs to root, and users cannot even read it. This causes postgres to not be able to open this file and therefore not be able to start the server, throwing the error seen in the original question.
By running
sudo chmod +r pg_hba.conf
I was able to make this file once again accessible to the postgres user and then after running
sudo service postgresql start
Was able to get the server running again.
WARNING: This will remove the database
Use command:
rm -rf /usr/local/var/postgres && initdb /usr/local/var/postgres -E utf8
WARNING: This will remove the database
Within zsh:
rm -rf /usr/local/var/postgres && initdb /usr/local/var/postgres -E utf8
This is the only thing that worked for me after countless hours trouble shooting.
Does the /etc/postgresql/9.6/main/postgresql.conf show that port being assigned? On my default Xubuntu Linux install, mine showed port = 5433 for some reason as best as I can remember, but I did comment out the line in that same file that said listen_addresses = 'localhost' and uncommented the line listen_addresses = '*'. So maybe start and check there. Hope that helps.
This works for me:
pg_ctl -D /usr/local/var/postgresql#9.6 stop;
brew services stop postgresql#9.6;
brew services start postgresql#9.6;
I was able to solve the issue by running:
sudo systemctl start postgresql#9.5-main
In my case Postgres was managed through Homebrew Services (i.e. started via brew services start postgresql#10 Terminal command for the Postgres 10 that I use), and for that setup I had to discover a couple of essential steps to do before I could apply any advice in this thread. So I want to share just that piece as it may help someone who has the same setup.
NOTE: all the commands below are to be run in Terminal.
To give a quick background: After upgrading to macOS Big Sur I discovered that Postgres wasn't working and running psql results in the error mentioned in the original question above. I tried to start Postgres (via the brew services start postgresql#10 command), this resulted in a message Service postgresql#10 already started. If I tried to restart it (via the brew services restart postgresql#10) I got a message that it was stopped and then started successfully. But! This was a misleading message, and I spent quite some time searching for config issues etc. before discovering that the service was not started successfully in reality.
So, the way to investigate this is:
Make sure the service is started by running the brew services start postgresql#10 (the latter argument may be different depending on what your Homebrew package name is e.g. postgresql#12 or plain postgresql).
Run brew services list. This is the command that gives you the true state of the service. In my case it said that Postgres' status is error:
Name Status User Plist
postgresql#10 error Denis /Users/Denis/Library/LaunchAgents/homebrew.mxcl.postgresql#10.plist
redis started Denis /Users/Denis/Library/LaunchAgents/homebrew.mxcl.redis.plist
To investigate further open the config shown in the same command output in Plist column (I used nano /Users/Denis/Library/LaunchAgents/homebrew.mxcl.postgresql#10.plist to check it).
In the config look for the StandardErrorPath key, and open the file located in the value of that key, i.e. in the <string> tag following the key. In my case it was /usr/local/var/log/postgresql#10.log.
Open that log and check the latest error (I used nano /usr/local/var/log/postgresql#10.log and then Alt+/ to go to the end of the file).
Voila. That is the real error to investigate, which you can then look for in the previous answers or google for. I'm not covering the rest here, as the goal of this answer is to show how to find the real error if you use Homebrew Services to run Postgres. (In my case it was the lock file "postmaster.pid" already exists already covered in the previous answers, plus the path to check right in the error message, in my case /usr/local/var/postgresql#10).
In my case it was the lockfile postmaster.id that was not deleted properly during the last system crash that caused the issue. Deleting it with sudo rm /usr/local/var/postgres/postmaster.pid and restarting Postgres solved the problem.
I recommend you should clarify port that postgres.
In my case I didn't know which port postgres was running on.
lsof -i | grep 'post'
then you can know which port is listening.
psql -U postgres -p "port_in_use"
with port option, might be answer. you can use psql.
If non of the above answers are not working for you, then please try this one,
Many people have mentioned many solutions to this problem! But all of them forgot that, the same problem will arise when your disk don't have enough space or the space you are assigned for postgres is full
Check your system storage, if its full free up some space! then restart your postgres by sudo service postgresql restart or do a stop and start sudo service posgresql stop then sudo service postgresql start
This will solve the issue, it solved for me
I occasionally have the same issue but mostly after macOS upgrades. Shutting down and migrating to the new version usually fixes it for me(make changes according to your version). So first upgrade your postgresql
brew services stop postgresql#12
brew services start postgresql#12
brew postgresql-upgrade-database
This is mostly a temporary fix but since I couldn't find a better solution this works for me.
Update: If the issue says that another postmaster is running then try removing it from that location(your postmaster.pid location will be displayed to you)
rm /usr/local/var/postgres/postmaster.pid
Open your database manager and execute this script
update pg_database set datallowconn = 'true' where datname = 'your_database_name';
I had the same error when I create the SQL db in a VM. I had changed the default value of /etc/postgresql/9.3/main/postgresql.conf shared_buffers = 200MB to 75% of my total RAM. Well, I forgot to actually allocate that RAM in the VM. When I gave the command to make a new database, I received the same error.
Powered off, gave the baby its bottle (RAM) and presto, it worked.
The same thing happened to me as I had changed something in the /etc/hosts file. After changing it back to 127.0.0.1 localhost it worked for me.
just reinstall your pgsql with direct version sudo apt-get install postgresql-9.5 (u must remove the package before install new one)
I had similar problems just a while ago. After trying more than 5 suggestions I decided to go back to the basics and start from the beginning. Which meant removing my postgresql installation and following this guide upon re-installing postgresql. https://help.ubuntu.com/lts/serverguide/postgresql.html
Ubuntu 20
This Problem happened to me, as ubuntu pre-installed version of Postgresql-9.6 server was always down and after trying all the above answers it didn't start.
Solution:
I installed another version of Postgresql which is postgresql-13, using this command: sudo apt install postgresql it will install the latest version of postgresql.
I see if the server is online or down using this command: pg_lsclusters if the new version of postgresql is online, we will proceed to remove the old version of postgresql.
we will see all packages that are installed related to postgresql, using this command: dpkg -l | grep postgresql
Remove the old version, which is here postgresql-9.6. Using this command:
sudo apt-get --purge remove postgresql-9.6 postgresql-client-9.6 replace 9.6 with your old version number. Final remaining packages related to the latest Version 13:
Restart your postgresql latest version server, which is here postgresql-13. Using this command: sudo systemctl restart postgresql#13-main replace 13 in the command with your latest version number.
Now, if you try psql command you will get an error related to your user, as in the image:
To Remove the above error, The installation procedure created a user account called postgres that is associated with the default Postgres role, to switch over to the postgres account use this command: sudo -u postgres psql this command will log you into the interactive Postgres session. You can also set your password for this user using this command \password postgres.
Then change the Port to the deafult port of postgresql, which is 5432 as all application will try to connect to postgresql using this port by default, using this command: sudo nano /etc/postgresql/13/main/postgresql.conf, it will open postgresql configuration file, then search for port and change it to 5432. After that you need to restart the server using this command sudo systemctl restart postgresql#13-main. Note, Replace 13 in the command with your latest version.
If you want to create your own User/Role, use this command: sudo -u postgres createuser --interactive. The script will prompt you with some choices, as in the image and based on your responses, it will execute the correct Postgres commands to create a user to your specifications.
Tutorial: For more information on postgresql related commands
I couldn't connect using the psql command and kept getting the error Cannot connect to Server: No such file or directory.
Step 1: Check the status of the Postgres cluster
$ pg_lsclusters
Step 2: Restart the Postgres cluster
$ sudo pg_ctlcluster 12 main start
Make sure to replace 12 with your version of Postgres
Step 3: Check again and connect
$ pg_lsclusters
$ sudo -i -u postgres
$ psql
I got this error when I restored my database from last pg_basebackup backup file. After that when I tried to connect database(psql), I was getting the same error. The error was resolved, when I updated pg_hba.conf file and wherever "peer" authentication was there I replaced that with "md5" and then restarted postgres services. After that, the problem was resolved.
This error happened to me after my mac mini got un-plugged (so forced shutdown), and all I had to do to fix it was restart
I have the same issue with postgres 11 on my mac. I get this error every time after restart
psql: 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"?
As a temporary fix I do
brew services stop postgresql#11
brew services start postgresql#11
My problem happened after a brew update so I've ran
pg_ctl -D /usr/local/var/postgres start
and I've got this result:
FATAL: database files are incompatible with server 2021-07-07 13:27:21.692 CEST [70896] DETAIL: The data directory was initialized by PostgreSQL version 12, which is not compatible with this version 13.2. stopped waiting
I've ran
brew postgresql-upgrade-database
FATAL: could not load server certificate file "/etc/ssl/certs/ssl-cert-snakeoil.pem": No such file or directory
LOG: database system is shut down
pg_ctl: could not start server
I have a missing ssl-cert-snakeoil.pem file so i created it using make-ssl-cert generate-default-snakeoil --force-overwrite And it worked fine.
In my case, I had to run journalctl -xe, and it showed that my disk was full. I then deleted some .gz items from /var/log and I could again restart the postgresql.
I'm on Kali Linux. I had to remove the brew version of postgresql with
brew uninstall postgresql
sudo -u postgres psql got me into root postgres
Simply running these commands from the installation steps in the official PostgreSQL docs worked for me (I'm on Fedora 33):
# Optionally initialize the database and enable automatic start:
sudo /usr/pgsql-13/bin/postgresql-13-setup initdb
sudo systemctl enable postgresql-13
sudo systemctl start postgresql-13
RHEL Installation link
kali users pls do this
sudo service postgresql restart
I find I have the wreckage of two old PostgreSQL installations on Ubuntu 10.04:
$ pg_lsclustersVersion Cluster Port Status Owner Data directory Log file
Use of uninitialized value in printf at /usr/bin/pg_lsclusters line 38.
8.4 main 5432 down /var/lib/postgresql/8.4/main /var/log/postgresql/postgresql-8.4-main.log
Use of uninitialized value in printf at /usr/bin/pg_lsclusters line 38.
9.1 main 5433 down /var/lib/postgresql/9.1/main /var/log/postgresql/postgresql-9.1-main.log
$
Attempts to perform basic functions return errors, for instance:
createuser: could not connect to database postgres: 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"?
More information comes when I try to start the database server:
$ sudo /etc/init.d/postgresql start
* Starting PostgreSQL 9.1 database server
* Error: The cluster is owned by user id 109 which does not exist any more
...fail!
$
My question: how do I completely remove both clusters and set up a new one? I've tried removing, purging, and reinstalling postgresql, following the advice here: https://stackoverflow.com/a/2748644/621762. Now pg_lsclusters shows no clusters in existence, but the No such file or directory error persists when I try to createuser, createdb or run psql. What have I failed to do?
First, that answer you linked to was pretty unsafe - hand-editing /etc/passwd ?!? dselect where an apt wildcard would do? Crazy stuff. I'm not surprised you're having issues.
As for the no such file or directory messages: You need to make sure you have a running PostgreSQL server ("cluster") before you can use admin commands like createdb, because they make a connection to the server. The No such file or directory message is telling you that the server doesn't exist or isn't running.
Here's what's happening:
Ubuntu uses pg_wrapper to manage multiple concurrent PostgreSQL instances. The issues you're having are really with pg_wrapper.
Ideally you would've just used pg_dropcluster to get rid of the unwanted clusters. Unfortunately, by following bad advice it sounds like you've got your system into a bit of a messed-up state where the PostgreSQL packages are half-installed and kind of mangled. You need to either repair the install, or totally clean it out.
I'd clean it out. I'd recommend:
Verify that pg_lsclusters lists no database clusters
apt-get --purge remove postgresql\* - this is important
Remove /etc/postgresql/
Remove /etc/postgresql-common
Remove /var/lib/postgresql
userdel -r postgres
groupdel postgres
apt-get install postgresql-common postgresql-9.1 postgresql-contrib-9.1 postgresql-doc-9.1
It's possible that the apt-get --purge step will fail because you've removed the user IDs, etc. Re-creating the postgres user ID with useradd -r -u 109 postgres should allow you to re-run the purge successfully then delete the user afterwards.
This answer is not directly about removing a postgres instance, rather, about resoliving the issue,
Error: The cluster is owned by user ...
I got this error while trying to spin up a docker container pointed to a postgres data directory that was produced via a different container (on a different host machine).
The error is directly related to directory ownership. In my case, the system was unable to find the user that certain postgres directories was owned by in the current environment. By re-owning those directories to the right user resolves the issue. Following is an example mapping (that worked for me):
chown -R postgres:postgres /var/lib/postgresql
chown -R postgres:postgres /etc/postgresql
chown -R postgres:postgres /var/log/postgresql
chown -R postgres:postgres /var/run/postgresql