Set password in postgreSQL

 The error is
Unable to connect to server: connection failed: connection to server at "127.0.0.1", port 5432 failed: FATAL: password authentication failed for user "postgres" connection to server at "127.0.0.1", port 5432 failed: FATAL: password authentication failed for user "postgres"

The "password authentication failed for user 'postgres'" error usually happens when:

• The password is incorrect.
• The PostgreSQL server is not configured properly.
• The pg_hba.conf file is blocking the connection.

---

✅ Fix the Error Step-by-Step:

1. Restart PostgreSQL Service

First, make sure PostgreSQL is running.

sudo systemctl restart postgresql
sudo systemctl status postgresql

If it's not running, start it:

sudo systemctl start postgresql

---

2. Login as postgres User and Reset Password

Switch to the postgres user:

sudo -i -u postgres

Now open psql:

psql

Reset the password:

ALTER USER postgres PASSWORD 'newpassword';

Exit psql:

\q

Exit user:

exit

---

3. Update Authentication Method

If the problem is still there, configure pg_hba.conf.

Open the configuration file:

sudo nano /etc/postgresql/*/main/pg_hba.conf

Find this line:

local   all             postgres                                peer

Replace peer with md5:

local   all             postgres                                md5

---

4. Restart PostgreSQL Again

sudo systemctl restart postgresql

---

5. Test the Connection

Try connecting again from pgAdmin with the new password.

---

🎯 Final Tip

If you still can't connect, check the PostgreSQL logs:

sudo journalctl -u postgresql

✅ This solution should fix the password authentication failed error!

Install pgAdmin in Ubuntu

 

✅ Install pgAdmin on Ubuntu

To install pgAdmin (a web-based GUI for PostgreSQL) on Ubuntu, follow these steps:

---

1. Update Package List

sudo apt update
sudo apt upgrade

---

2. Install Required Packages

sudo apt install curl ca-certificates gnupg

---

3. Add pgAdmin Repository

curl https://www.pgadmin.org/static/packages_pgadmin_org.pub | sudo tee /usr/share/keyrings/packages-pgadmin-org.gpg >/dev/null
sudo sh -c 'echo "deb [signed-by=/usr/share/keyrings/packages-pgadmin-org.gpg] https://ftp.postgresql.org/pub/pgadmin/pgadmin4/apt/$(lsb_release -cs) pgadmin4 main" > /etc/apt/sources.list.d/pgadmin4.list && apt update'

---

4. Install pgAdmin

For the Web Version:

sudo apt install pgadmin4-web

OR
For the Desktop Version:

sudo apt install pgadmin4-desktop

---

5. Configure pgAdmin Web (Optional)

To configure the web-based pgAdmin:

sudo /usr/pgadmin4/bin/setup-web.sh

Follow the instructions to set up:

• Email
• Password

---

6. Start pgAdmin

• Web Version: Open your browser and go to:

http://localhost/pgadmin4

• Desktop Version:

pgadmin4

---

🎯 Uninstall pgAdmin

If you want to remove pgAdmin:

sudo apt remove pgadmin4
sudo apt autoremove

✅ Now pgAdmin is installed and ready to use!

Install PostgreSQL in ubuntu

To install PostgreSQL on Ubuntu, follow these steps:

✅ Steps to Install PostgreSQL on Ubuntu

1. Update Package List

sudo apt update
sudo apt upgrade

2. Install PostgreSQL

sudo apt install postgresql postgresql-contrib

3. Check PostgreSQL Service Status

sudo systemctl status postgresql

If running, it will show active (running).

4. Start/Stop/Restart Service

• Start: sudo systemctl start postgresql
• Stop: sudo systemctl stop postgresql
• Restart: sudo systemctl restart postgresql

---

✅ Access PostgreSQL

Switch to the default PostgreSQL user:

sudo -i -u postgres

Then access the PostgreSQL prompt:

psql

You will see:

postgres=#

---

✅ Create a New Database

CREATE DATABASE mydb;

✅ Create a New User

CREATE USER myuser WITH PASSWORD 'mypassword';

✅ Grant Privileges

GRANT ALL PRIVILEGES ON DATABASE mydb TO myuser;

---

✅ Exit PostgreSQL

\q

Exit user:

exit

---

🎯 Enable Remote Access (Optional)

1. Edit postgresql.conf:

sudo nano /etc/postgresql/*/main/postgresql.conf

Uncomment:

listen_addresses = '*'

2. Edit pg_hba.conf:

sudo nano /etc/postgresql/*/main/pg_hba.conf

Add:

host    all             all             0.0.0.0/0               md5

3. Restart PostgreSQL:

sudo systemctl restart postgresql

---

✅ Now PostgreSQL is installed and ready to use!