source: Install Validation.md

# Install validation

With a lot of configuration possibilities, manually editing config.php means it's not
uncommon that mistakes get made. It's also impossible to validate user input in config.php when you're just using a text editor :)

So, to try and help with some of the general issues people come across we've put together a simple validation tool which at present will:

 - Validate config.php from a php perspective including whitespace where it shouldn't be.
 - Connection to your MySQL server to verify credentials.
 - Checks if you are running the older alerting system.
 - Checks your rrd directory setup if not running rrdcached.
 - Checks disk space for where /var/www/librenms is installed.
 - Checks location to fping
 - Tests MySQL strict mode being enabled
 - Tests for files not owned by librenms user (if configured)

Optionally you can also pass -m and a module name for that to be tested. Current modules are:

 - mail - This will validate your mail transport configuration.
 - dist-poller - This will test your distributed poller configuration.
 - rrdcheck - This will test your rrd files to see if they are unreadable or corrupted (source of broken graphs).

You can run validate.php as `root` by executing `./validate.php` within your install directory.

The output will provide you either a clean bill of health or a list of things you need to fix:

**OK** - This is a good thing, you can skip over these :)

**WARN** - You probably want to check this out.

**FAIL** - This is going to need your attention!

### Validate from the WebUI
You can validate your LibreNMS install from the WebUI, using the nav bar and clicking on the little Gear Icon -> Validate Config.
![Validate Config Icon](/img/validate-config-icon.png)
Then You should see the results of validate. 
Below is just example of the results.

![Validate results](/img/validate-results.png)
