Simple Threshold Trigger

Let’s say you measure how much free space is left on your HDD and store this value as DevOps.my_server.hdd.freespace_mbytes in Graphite. Maybe you want to get an email when you have less than 50 GB left (it’s not a big problem), and a Pushover notification when you have less than 1 GB left (you really need to delete something asap).

You can easily accomplish this by adding a trigger in Moira’s Simple Mode:

simple trigger

Graphite Target

You can specify a single metric like we did here: DevOps.my_server.hdd.freespace_mbytes.

You can also specify multiple metrics like DevOps.*.hdd.freespace_mbytes. All metrics will be monitored separately, and you will get separate notifications for each metric.

You can even use Graphite functions like movingAverage(DevOps.my_server.hdd.freespace_mbytes, 10). Moira understands everything that Graphite itself understands. See appropriate documentation.

Thresholds

In simple mode you need to specify two threshold values: WARNING and ERROR. Note that Moira will automatically switch to raising or falling mode according to these settings. In our example, warning threshold is greater than error threshold. In this case, Moira will consider any value less than 50000 a warning and less than 1000 an error, which is what we want. In other cases, you may need to consider large values a problem - then you should make error threshold greater than warning.

Tags

In Moira, you cannot subscribe to a single trigger. Instead, you should categorize your triggers by tags and subscribe to a tag. It may look like an overkill here, but when you have dozens of triggers, you are much better off with tags, because you don’t have to enter your contact information over and over again. Tags also help to filter information on main screen:

main screen with filter

You can add as many tags as you want.

Subscriptions

Proceed to the Setting Up Your Subscriptions page to learn how to set up a subscription to your trigger.