PostgreSQL, also known as Postgres, is a free and open-source relational database management system that runs on multiple platforms including Linux. It is widely used by developers due to its scalability and reliability. In this blog, we will discuss how to check the Postgres service status in Linux. We will provide 3 different methods to check the status, along with their steps and precautions.
Video Tutorial:
Requirements
– A Linux operating system (such as Ubuntu, Fedora, or CentOS)
– PostgreSQL installed and running on your Linux system.
What should be paid attention to?
Before checking the Postgres service status, ensure that the database cluster is initialized and running. Also, make sure that you have administrative privileges to perform the following commands.
Method 1: Using Systemctl
Systemctl is a command used to control the systemd system and service manager. The following are the steps to check Postgres service status using systemctl:
1. Open the terminal on your Linux system and log in as a root user using the sudo -i command.
2. Type systemctl status postgresql to check the service status.
3. If the service is running, the output will show you the service status, active (running), and the date and time when it was started.
4. If the service is not running, the output will show you the service status, inactive (dead), and the reason for the failure.
Q: What should I do if the service is not running?
A: If the service is not running, use the systemctl start postgresql command to start the service.
Method 2: Using service command
The service command is another way to control system services on a Linux system. The following are the steps to check Postgres service status using the service command:
1. Open the terminal on your Linux system and log in as a root user using the sudo -i command.
2. Type service postgresql status to check the service status.
3. If the service is running, the output will show you the service status, active (running), and the date and time when it was started.
4. If the service is not running, the output will show you the service status, inactive (dead), and the reason for the failure.
Q: What should I do if the service is not running?
A: If the service is not running, use the service postgresql start command to start the service.
Method 3: Using PG_CTL command
PG_CTL is a command-line utility that allows performing various administrative tasks in PostgreSQL. The following are the steps to check Postgres service status using PG_CTL:
1. Open the terminal on your Linux system and log in as a root user using the sudo -i command.
2. Type pg_ctl status -D /var/lib/pgsql/data to check the service status.
3. If the service is running, the output will show you the service status and the date and time when it was started.
4. If the service is not running, the output will show you the PostgreSQL cluster is not running.
Q: What should I do if the service is not running?
A: If the service is not running, use the pg_ctl start -D /var/lib/pgsql/data command to start the service.
Why can’t I check Postgres service status?
There are several reasons why you may not be able to check the Postgres service status in Linux:
1. The PostgreSQL service is not installed on your Linux system.
2. The PostgreSQL service is not running.
3. You do not have administrative privileges to check the PostgreSQL service status.
To fix these issues, ensure that PostgreSQL is installed and running on your system. Also, make sure that you have administrative privileges to perform the necessary commands.
Suggestions
– Always ensure that the Postgres service is running before using the database.
– If you encounter any issues while checking the service status, try restarting the service and checking again.
– Ensure that you have administrative privileges to perform the necessary commands.
Q: How can I restart the Postgres service?
A: To restart the Postgres service, use the systemctl restart postgresql or service postgresql restart command.
Q: Can I use the same commands to check the service status in Windows?
A: No, the commands used to check the Postgres service status in Linux are different from those used in Windows.
Q: How do I know which version of Postgres is installed on my Linux system?
A: To check the installed version of Postgres, use the postgres –version command.
Q: How can I start the Postgres service automatically on system boot?
A: Use the systemctl enable postgresql or chkconfig postgresql on command to start the service automatically on system boot.
Q: Can I change the default port of the Postgres service?
A: Yes, you can change the default port of the Postgres service in the postgresql.conf configuration file.
Conclusion
Postgres service status checking is an essential task for database administrators. In this blog, we have discussed 3 different methods to check the Postgres service status in Linux. We have also provided precautions and suggestions to keep in mind while performing the necessary commands. By following our instructions, you can easily check the Postgres service status and ensure the smooth functioning of your database.
