Another option to change is the maximum number of connections per user:
```
mail_max_userip_connections = 100
```
Another important option is the `default_process_limit` (defaults to 100). If high-security mode is enabled you'll need to make sure this count is higher than the maximum number of users that can be logged in simultaneously.
For major configuration changes it’s best to override the `dovecot` configuration files. For each configuration file you want to override, add a list entry under the `volumes:` key.