Here are a few steps you can take to resolve connect to db with another IP:

Verify the PostgreSQL server is running: Ensure that the PostgreSQL server is up and running on the target machine with the IP address 192.168.13.240. You can check the status of the PostgreSQL service on that machine and restart it if necessary.

Check the PostgreSQL server configuration: Verify that the PostgreSQL server is configured to accept connections from remote hosts. By default, PostgreSQL often listens only on the local interface (localhost). You may need to update the PostgreSQL server's configuration file (typically postgresql.conf) to allow connections from external IP addresses. Look for the listen_addresses parameter and set it to '*' to listen on all available network interfaces. Once you've made the changes, restart the PostgreSQL service.

Verify network connectivity: Ensure that there is network connectivity between the machine running your Django application and the machine hosting the PostgreSQL server. Check if there are any firewall rules or network configurations that might be blocking the connection. You can try pinging the PostgreSQL server from the Django application server to verify network connectivity.

Verify the PostgreSQL server's port: By default, PostgreSQL listens on port 5432. Double-check that the PostgreSQL server is configured to use the default port or update the PORT value in your Django settings if your PostgreSQL server is running on a different port.

Check the database credentials: Verify that the database credentials (username, password, database name) provided in your Django settings are correct and match the credentials configured on the PostgreSQL server.

Test the connection manually: You can try to establish a manual connection to the PostgreSQL server using tools like psql or a PostgreSQL client library to ensure that the server is accessible from the Django application server.