LISTEN

In a distributed setup, you can use this <host>:<service>:LISTEN_IP token to control which IPs the services bind to so that you can make sure that services are not overexposed than necessary.

By default, services bind to the IP address corresponding to the <host>:PUBLIC_FQDN token. However, you can override this using the <host>:<service>:LISTEN_IP token.

A few use cases:

In a distributed setup, you may want to bind a particular IP address of the TeamForge database server (PostgreSQL server) to the ctfcore-database service:
```
server-01:ctfcore-database:LISTEN_IP = 1.2.3.4
```
To bind the mail service to a particular IP:
```
localhost:mail:LISTEN_IP = 1.2.3.4
```
To make TeamForge listen to a specific IP of a particular server, say the SCM server.
```
myscmserver:LISTEN_IP = 1.2.3.4
```
To bind all your services to one IP address (typically in a single server setup):
```
localhost:LISTEN_IP = 1.2.3.4
```

Note: You cannot use more than one IP address with the LISTEN_IP token.