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'password authentication failed for user "postgres"'

I have installed PostgreSQL 8.4, Postgres client and Pgadmin 3. Authentication failed for user "postgres" for both console client and Pgadmin. I have typed user as "postgres" and password "postgres", because it worked before. But now authentication is failed. I did it before a couple of times without this problem. What should I do? And what happens?

psql -U postgres -h localhost -W
Password for user postgres: 
psql: FATAL:  password authentication failed for user "postgres"
FATAL:  password authentication failed for user "postgres"
In my case the connection fails because the password is too complex ...
Be sure to read all the way down this page. I had to do several things to get this working. First, the ALTER step, then editing my pg_hba.conf file, then restarting postgres.
Also ensure that you have not two Postgres instances running: one on Windows, one in Docker. Docker did not report to me that the port was already taken. So, the tool connected to the Windows machine Postgres, whereas in the Docker postgers, everything was fine.

B
Brian

If I remember correctly the user postgres has no DB password set on Ubuntu by default. That means, that you can login to that account only by using the postgres OS user account.

Assuming, that you have root access on the box you can do:

sudo -u postgres psql

If that fails with a database "postgres" does not exists error, then you are most likely not on a Ubuntu or Debian server :-) In this case simply add template1 to the command:

sudo -u postgres psql template1

If any of those commands fail with an error psql: FATAL: password authentication failed for user "postgres" then check the file /etc/postgresql/8.4/main/pg_hba.conf: There must be a line like this as the first non-comment line:

local   all         postgres                          ident

For newer versions of PostgreSQL ident actually might be peer. That's OK also.

Inside the psql shell you can give the DB user postgres a password:

ALTER USER postgres PASSWORD 'newPassword';

You can leave the psql shell by typing CtrlD or with the command \q.

Now you should be able to give pgAdmin a valid password for the DB superuser and it will be happy too. :-)


Note, that pg_hba.conf must have the postgres user set to ident in order for the first steps to work. If you already set it to md5 or something else, you won't be able to auto-login.
Very nice one. To other new users, DON'T FORGET THE SEMICOLON at the end of the ALTER USER line.
@itsols You said: "Very nice one. To other new users, DON'T FORGET THE SEMICOLON at the end of the ALTER USER line"... You just ended a four hour ordeal!! I feel sooooo stupid and grateful right now. :-D
I'm not so new, I configured PostgreSQL dbs many times, but I FORGOT THE SEMICOLON! ;) AGAIN ;)
From the Comprehensive manual, postgresql.org/files/documentation/pdf/12/postgresql-12-A4.pdf, section 20.5: "If no password has been set up for a user, the stored password is null and password authentication will always fail for that user.". Thus, since the installation doesn't ask for a password, it is not set. This should be said in every tutorial, since it's one of the first things new users do, try to connect from a nice GUI...
D
Diego

The response of staff is correct, but if you want to further automate can do:

$ sudo -u postgres psql -c "ALTER USER postgres PASSWORD 'postgres';"

Done! You saved User = postgres and password = postgres.

If you do not have a password for the User postgres ubuntu do:

$ sudo passwd postgres


Careful if your password contains interesting characters like '!'
As you are having the trouble to change the password of the user, a good practice would be to create a new user and a new password: Insde the SQL prompt, it would be: postgres-# CREATE ROLE your_username WITH LOGIN CREATEDB ENCRYPTED PASSWORD 'your_password'; A discussion about the use of the postgres user can be found in stackoverflow.com/questions/2172569/…
The only solution that worked for me (Kali Linux 2020)
Worked for me!! Thanks. Note that we need to set the username and password as it is in the knex.ts or js file
A
Andronicus

This was frustrating, most of the above answers are correct but they fail to mention you have to restart the database service before the changes in the pg_hba.conf file will take affect.

so if you make the changes as mentioned above:

local all postgres ident

then restart as root ( on centos its something like service service postgresql-9.2 restart ) now you should be able to access the db as the user postgres

$psql
psql (9.2.4)
Type "help" for help.

postgres=# 

Hope this adds info for new postgres users


On ubuntu type: sudo service postgresql restart
for RHEL7 use sudo systemctl restart postgresql.service
What about on mac?
For mac, checkout this question on SO stackoverflow.com/questions/7975556/…
Thanks Miguel. I've cahnged the password manually, and my pgAdmin did not connect to the databese until I restart the postgres server.
s
stevek-pro

Edit the pg_hba.conf file, for Debian on /etc/postgresql/9.3/main/pg_hba.conf and for Red Hat/IBM derivates at /var/lib/pgsql/9.4/data/pg_hba.conf

Change all authentication methods to trust.

Change Linux Password for postgres user.

Restart Server.

Login with psql -h localhost -U postgres and use the just set Unix password.

If it works you should re-set the pg_hba.conf file to values with md5 or ident methods and restart.


If you get completely stuck, this is the only guaranteed method. Change all methods to trust, restart db, then as root: sudo su - postgres, next set/fix/unset password for postgres db (and in the shell, if necessary), then restore to secure md5 or ident methods and restart again so values stick. By the way, on Cent/RedHat 9.4 the file is located at: /var/lib/pgsql/9.4/data/pg_hba.conf
Thanks Papak, the file location on cent os was of great help.
J
Jose Kj

For those who are using it first time and have no information regarding what the password is they can follow the below steps(assuming you are on ubuntu):

Open the file pg_hba.conf in /etc/postgresql/9.x/main sudo vi pg_hba.conf 2.edit the below line local all postgres peer to local all postgres trust Restart the server sudo service postgresql restart Finally you can login without need of a password as shown in the figure

Ref here for more info


Getting an error W10 : Warning: Changing a readonly File Also can't open file for writing
yeah, forgot to add sudo, my bad .
A
Alvaro Rodriguez Scelza

When you install postgresql no password is set for user postgres, you have to explicitly set it on Unix by using the command:

sudo passwd postgres

It will ask your sudo password and then promt you for new postgres user password. Source


Funny how I've never seen this before! This is by far the easiest way to change the password in my opinion.
F
Francisco Puga

Try to not use the -W parameter and leave the password in blank. Sometimes the user is created with no-password.

If that doesn't work reset the password. There are several ways to do it, but this works on many systems:

$ su root
$ su postgres
$ psql -h localhost
> ALTER USER postgres with password 'YourNewPassword';

a
ardilgulez

As a rule of thumb: YOU SHOULD NEVER EVER SET A PASSWORD FOR THE POSTGRES USER.

If you need a superuser access from pgAdmin, make another superuser. That way, if the credentials for that superuser is compromised, you can always ssh into the actual database host and manually delete the superuser using

sudo -u postgres -c "DROP ROLE superuser;"

What's the reason for this rule of thumb?
So that you can never have all your superusers conpromised.
How can setting a password for postgres lead to having all superusers compromised?
setting password doesn't lead to having all superusers compromised but not setting the password will guarantee that you'll never have all superusers compromised. the reason is: when you don't set the password, any password login attempt to postgres user will be denied whereas you can still use it yourself by trust.
D
Dino

Once you are in your postgres shell, Enter this command

postgres=# \password postgres

After entering this command you will be prompted to set your password , just set the password and then try.


I
Iharob Al Asimi

If you are trying to login postgres shell as postgres user, then you can use following commands.

switch to postgres user

# su - postgres

login to psql

# psql

Hope that helps


su - postgres asks for a password on posgresql 9.5 on Ubuntu 16.04
su - postgres is the command that the official fedora documentation suggests, but I too get a password prompt. To get round that I followed this postgres forum email that uses the same command as the accepted answer here: sudo -u postgres psql. Don't forget to init and start the database server.
C
Chen Lim

Ancient thread, but I wasted half a day dealing with this in 2020, so this might help someone: Double-check your postgres port (on Ubuntu, it's in /etc/postgresql/9.5/main/postgresql.conf). The psql client defaults to using port 5432, BUT in my case, the server was running on port 5433. The solution was to specify the -p option in psql (e.g. psql --host=localhost --username=user -p 5433 mydatabase).

If you leave off the --host parameter, psql will connect via a socket, which worked in my case, but my Golang app (which uses TCP/IP) did not. Unfortunately, the error message was password authentication failed for user "user", which was misleading. The fix was to use a url connection string with the port (e.g. postgres://user:password@localhost:5433/mydatabase).

My setup was Ubuntu 18.04 on Digital Ocean, with postgres 9.5 installed via apt-get, so not sure why this happened. Hope this saves you some time.


J
Jitender Kumar

I faced the same error on Windows 10. In my case, when I setup the Postgres, my username was postgres by default. But when I ran the command psql, it as showing my the username as jitender which is my machine name, and I don't know why this username had been setup.

Anyway to solved it, I did the following steps: Run the command psql --help

In the output, look for the Connection Option, here you will see your default user, in my case it as jitender.

You will also get the command to set the anoter username, which should be psql --username postgres. You set the username whatever you require, and that's all, problem got solved.


I found that I have to use --username=postgres on everyone command. e.g. createdb --username=postgres mydb which is super annoying. I tried doing psql --username but this brought up a DB prompt and the default username was not changed.
S
Szeryf

If you see error

FATAL:  password authentication failed for user "postgres"

and you are sure that your password is correct, check that the password has any special characters, especially "%" or slashes. In my case, it was "%" in the password string. After removing this symbol, everything works fine.


looks like "!" in password causes same issues like "%" when connecting via psql
t
tokhi

Here are some combinations which I tried to login:

# login via user foo
psql -Ufoo -h localhost

sudo -u postgres psql postgres

# user foo login to postgres db
psql -Ufoo -h localhost -d postgres

f
frank

Time flies!

On version 12, I have to use "password" instead of "ident" here:

local   all             postgres                                password

Connect without using the -h option.


ö
ömer faruk

First of All password crate

ALTER USER postgres with encrypted password 'postgres';

then service restart:

sudo systemctl restart postgresql.service

End.


FYI - Inside pg db docker container running first command - alter User... is sufficient. No need to restart service
M
Mohamed Ahmed

Follow these steps :

sudo -u postgres -i psql \password postgres

After that, enter your password twice.

Then use that password in the pgAdmin4.


C
Community

I just wanted to add that you should also check if your password is expired.

See Postgres password authentication fails for details.


Please add some details and a summary of what that link provides in case in the future the link no longer exists. Otherwise this is likely to be flagged as a low-quality/link only answer.
s
sɐunıɔןɐqɐp

In my case, Ubuntu 20.04 Postgresql 12 was using the wrong port.

I've checked /etc/postgresql/12/main/postgresql.conf and realized it was 5433 instead of 5432.


N
Niyongabo Eric

The answer is @diego

I want to add some explanations of how I fixed error and I hope it will help other folks: ERROR: password authentication failed for user "postgres"

On Window

Make sure you download Postgres software, install it, create and confirm password and make sure its not complicated with some symbols and characters.

Open window, click SQL Shell (PSQL) and access it and create database

Create connection string like postgres://postgres:your_password@localhost:port/your_database

On WSL

Follow Microsoft documentation

After successful installation

 // Open postgres
 su postgres
 
 // Type psql and hit enter
 psql

 // Create a user postgres if not exist or any other user you want 
 CREATE USER your_user_db WITH PASSWORD 'match_password_with_db_password';
 

 // Give user password same as the one you set up for postgres db
 ALTER USER your_user_db WITH PASSWORD 'match_password_with_db_password';

 // Restart the server
 sudo service postgresql restart

D
David Uvm

i had a similar problem. Ubuntu was left me log in in console with any password for superuser. Except when i connected with -h localhost in psql line command.

I Observed too that "localhost:8080/MyJSPSiteLogIn" - showed: Fatal: autentication error with user "user".

pg_hba.conf was ok.

I noted had two versions of postgres running in the same service.

Solved - uninstalling inutil version.


a
amoljdv06

I had faced similar issue. While accessing any database I was getting below prompt after updating password "password authentication failed for user “postgres”" in PGAdmin

Solution:

Shut down postgres server Re-run pgadmin pgadmin will ask for password. Please enter current password of mentioned user

Hope it will resolve your issue

https://i.stack.imgur.com/FsLCZ.png


A
Aremu Ibrahim

This happens due to caching.

When you run, php artisan config:cache, it will cache the configuration files. Whenever things get change, you need to keep running it to update the cache files. But, it won't cache if you never run that command.

This is OK for production, since config don't change that often. But during staging or dev, you can just disable caching by clearing the cache and don't run the cache command

So, just run php artisan config:clear, and don't run the command previously to avoid caching.

Check original post

Password authentication failed error on running laravel migration


v
viggy28

In my case, its Password was longer than 100 characters. Setting it to a smaller character password worked.

Actually I am wondering is there a reference somewhere to that.


M
Muhammad

Please remember if you have two versions of Postgres installed you need to Uninstall one of them, in my case on MacOS I had one version installed via .dmg and one via brew.

What worked for me was to uninstall the one installed via .dmg using the following steps

Go to /Library/PostgreSQL/13. Open uninstall-postgres.app.

then try

psql postgres

it should work.


o
officialrahulmandal

Answer given is almost correct just missing some pointers which i'll be taking care of in my solution

First make sure your user have a sudo access if not you can use the below command to add your user as sudo user :-

sudo adduser <username> sudo

The change will take effect the next time the user logs in.

i) Now go to sudo vim /etc/postgresql/<your_postgres_version>/main/pg_hba.conf file and look for line that says :

local   all             postgres                                md5 #peer

and comment that. Just below that line there must be a commented line that says:

local   all             postgres                                peer

or for older versions it'll be :-

local   all         postgres                          ident

Uncomment that line.

ii) Now restart the postgres by using any of these commands :-

sudo /etc/init.d/postgresql restart

OR

sudo service postgresql restart

iii) Now you can simply log into postgres using the following command :

sudo -u postgres psql

iv) once you're in you can create any operation you want to in my case i wanted to create a new database you can do the same using below command :

CREATE DATABASE airflow_replica;

V
Vitor Oliveira

In my case it was so simple! I was taken error in application JAVA Spring because I needed remember the Database Superuser, it is showed during the install process PostgreSQL, in my case the datasource would be postgres. So, I added correctly the name and it works!


S
Sid

Open pg_hba.conf in any text editor (you can find this file in your postgres instalation folder); Change all the methods fields to trust (meaning you don't need a password for postgre); Run in your console this comand: "alter user postgres with password '[my password]';" | psql -U postgres (meaning to alter some user password for [my password] for the user as parameter -U postgres) Et voilà (don't forget to change back the method from trust for the one that should be best for you)

I hope this help someone someday.


C
Community

I hope this will help you short of time. You can change the password of postgres sql by using bellow command.

Command

sudo -u postgres psql

And next you can update the password

Command

Alter user postgres password 'YOUR_NEW_PASSWORD';


Your answer just contains information, that has already been added: stackoverflow.com/a/7696398/8283469