To run gmid in daemon mode a configuration file is needed. The format of the configuration file is described in the manpage and is quite flexible, but for simple setup something like the following should be enough:
```sample configuration file
# /etc/gmid.conf
server "example.com" {
cert "/path/to/certificate"
key "/path/to/private-key"
root "/var/gemini/example.com"
}
```
A X.509 (TLS) certificate can be generated using contrib/gencert
Optionally copy ‘example.com.pem’ and ‘example.com.key’ to another location.
Make sure that the ‘cert’ and ‘key’ options in the configuration file points to these files.
Then running gmid is as easy as
```running gmid
$ gmid -c /etc/gmid.conf
```
## Securing your gmid installation
gmid employs various techniques to prevent the damage caused by bugs, but some steps needs to be done manually.
If gmid was installed from your distribution package manager, chance are that it already does all of this and is also providing a service to run gmid automatically (e.g. a systemd unit file, a rc script, …) Otherwise, it’s heavily suggested to create at least a dedicated user.
### A dedicated user
Ideally, gmid should be run with root privileges and to drop privileges to a local user. This way, the created certificates can be readable only by root. For example, on GNU/linux systems a ‘gmid’ user can be created with:
Please consult your OS documentation for more information on the matter.
The configuration then needs to be adjusted to include the ‘user’ directive at the top:
```how to use the ‘user’ option
# /etc/gmid.conf
user "gmid"
server "example.com" { … }
```
gmid then needs to be started with root privileges, but will then switch to the provided user automatically. If by accident the ‘user’ is forgotten and gmid is running as root, it will complain loudly in the logs.
### chroot
It’s a common practice for system daemons to chroot themselves into a directory. From here on I’ll assume /var/gemini, but it can be any directory.
A chroot on UNIX-like OS is an operation that changes the “apparent” root directory (i.e. “/”) from the current process and its child. Think of it like imprisoning a process into a directory and never letting it escape until it terminates.
Using a chroot may complicate the use of CGI scripts, because then all the dependencies of the scripts (like sh, perl, or other libraries) needs to be installed inside the chroot too. For this very reason gmid supports FastCGI too.
The chroot feature requires a dedicate user, see the previous section.
To chroot gmid inside a directory, use the ‘chroot’ directive in the configuration file:
```how to use the ‘chroot’ option
# /etc/gmid.conf
# the given directory, /var/gemini in this case, must exists.
chroot "/var/gemini"
```
Note that once ‘chroot’ is in place, every ‘root’ directive is implicitly relative to the chroot, but ‘cert’ and ‘key’ aren’t!
For example, given the following configuration:
```example configuration using chroot
# /etc/gmid.conf
user "gmid"
chroot "/var/gemini"
server "example.com" {
cert "/etc/ssl/example.com.pem"
key "/etc/ssl/example.com.key"
root "/example.com"
}
```
The certificate and the key path are the specified ones, but the root directory of the virtual host is actually “/var/gemini/example.com/”.