TwinCAT Runtime Linux^®

	These instructions refer to version 17 of PostgreSQL.

Installation of PostgreSQL

Connect to the PackageManager of TwinCAT Runtime Linux® to install the corresponding package.

1. Update the packages.

sudo apt update

2. Install the PostgreSQL database server.

sudo apt install postgresql-17

3. Activate the PostgreSQL service.

The database has been successfully installed and the service started.

sudo systemctl start postgresql

Initializing PostgreSQL

1. Switch to the database user

sudo -i -u postgres

2. Start psql

psql

3. Initialize the database.

Initdb

4. Change the default password of postgres

\password postgres

5. Exit psql

\q

6. Log out.

The database has been successfully initialized and started.

exit

Settings for access via the network

1. Create a configuration file in the /etc/nftables.conf.d/ directory with the name 00-postgre.conf, for example

sudo nano /etc/nftables.conf.d/00-postgre.conf

2. Insert the following content and adjust the values to your network requirements:

table inet filter {
  chain input {
    # accept PostgresSQL
    tcp dport 5432 accept
  }
}

3. Save and close the configuration file.

4. Load the new rule with the command

sudo systemctl reload nftables

5. Check the settings and make sure that the configuration has been applied correctly.

Port 5432 has been enabled for the PostgreSQL database.

sudo nft list ruleset

6. Open postgresql.conf to adjust the "listen_addresses".

sudo nano /etc/postgresql/17/main/postgresql.conf

7. Change the entry listen_addresses to '*' and remove the # to activate the line.

# - Connection Settings -

listen_addresses = '*'          # what IP address(es) to listen on;
                                        # comma-separated list of addresses;
                                        # defaults to 'localhost'; use '*' for all
                                        # (change requires restart)

8. Save and exit the editor.

9. Open pg_hba.conf to adjust the security settings.

sudo nano /etc/postgresql/17/main/pg_hba.conf

10. Adjust the entry host all all 127.0.0.1/32 or add a new one. Change the method to md5.

By default, 127.0.0.1/32 is entered as local only. If other systems are to have access to the database, the corresponding IP address must be set.
Notice Alternatively, 0.0.0.0/0 can be used as the IP address, in which case all requests will be allowed. This can pose a safety risk!

# TYPE  DATABASE        USER            ADDRESS                 METHOD

# "local" is for Unix domain socket connections only
local   all             all                                     peer
# IPv4 local connections:
host    all             all             127.0.0.1/32            scram-sha-256
# IPv6 local connections:
host    all             all             ::1/128                 scram-sha-256
# Allow replication connections from localhost, by a user with the
# replication privilege.
local   replication     all                                     peer
host    replication     all             127.0.0.1/32            scram-sha-256
host    replication     all             ::1/128                 scram-sha-256

11. Save and exit the editor.

12. Restart the service.

Thanks to the new configuration, your database is now accessible over the network.

sudo systemctl restart postgresql

Further Information

Docker^®