This tutorial will show you how to check that the PostgreSQL Server service is running on your Linux system.
To install PostgreSQL follow our tutorial here.
Checking PostgreSQL is Running on Ubuntu/Debian
To check whether the PostgreSQL server service is running successfully on your Debian or Ubuntu system, run:
sudo systemctl status postgresql
Checking the Firewall
By default PostgreSQL runs on port 5432 and is not restricted by host name.
When installing PostgreSQL on Ubuntu, usually a firewall rule will be created automatically allowing access to the database server.
You can confirm this by running the nmap command:
sudo nmap localhost
This will show the ports and service that are open on your machine – check through the list and make sure that postgresql is listed next to the port number 5432.
PORT STATE SERVICE 80/tcp open http 631/tcp open ipp 5432/tcp open postgresql
If it is not listed, you can open the firewall port using the ufw command:
sudo ufw allow 5432/tcp
If you have configured different a different hostname or port from the default, you may need to update your firewall rules to match.
Checking PostgreSQL is Running on Arch Linux
The process to check whether PostgreSQL is running is the same on Arch Linux, simply run:
sudo systemctl status postgresql
Checking the Firewall
Again, the nmap command is useful here for checking that the default PostgreSQL port of 5432 is open on your system:
sudo nmap localhost
Which will output something like:
PORT STATE SERVICE 80/tcp open http 631/tcp open ipp 5432/tcp open postgresql
If this port is not on the list, use ufw to allow the port through the firewall:
sudo ufw allow 5432/tcp
If you’ve changed from the default PostgreSQL port in your configuration, you will need to adjust your firewall rule to match.
Checking PostgreSQL is Running on Red Hat, Fedora, Centos, etc
Like Ubuntu and Arch, you can use the systemctl command to check the status of the PostgreSQL service on Red Hat based distributions:
sudo systemctl start postgresql.service
Checking the Firewall
The firewall-cmd command can be used to check that the default PostgreSQL port of 5432 is open on Red Hat based distributions:
firewall-cmd --list-all
postgressql and its port should be shown in the outputted list. If it is not, you can grant the PostgreSQL service network access through the firewall by running:
firewall-cmd --zone=public --permanent --add-service=postgresql
…or run the following to open the port:
firewall-cmd --zone=public --permanent --add-port 5432/tcp
Once changes have been made, apply them by reloading the firewall rules:
firewall-cmd --reload
Other Linux Distributions
Most modern Linux distributions (based on systemd) will use the same systemctl syntax as above to check whether a service is running.
Checking the Firewall
In the unlikely scenario where you do not have access to ufw or firewall-cmd, you can write your own iptables rules to allow traffic through your systems firewall.
To continue your PostgreSQL journey, head back to our index that lists our full PostgreSQL guide.
