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openHAB: timestamp from last Item update

If openHAB has a Persistence service configured, the time of the last Item update (and a couple other times) is available in Rules. This makes it quite handy to check if a certain item hasn't been updated in a long time.

Grafana: select host for a dashboard

InfluxDB is running on a Raspberry Pi in my home network (with separate attached disk), and I installed a Grafana on top of it, to visualize crucial data.


Monitor additional details in Telegraf with the "Exec" input filter

After installing Telegraf and hooking up everything into InfluxDB, I was missing the status of my backups. Every system here creates encrypted backups every night, and stores them on a central NAS, and off-site. But I want to know statistics about the backups, and see if something is not working.

I’m using Restic for the backups (will blog about this another time). However Telegraf does not support Restic directly, I need a few workarounds. This blog post however is not directly about monitoring the backups, but about how to write your own plugin for Telegraf.


Install Telegraf using Ansible

I have an InfluxDB up and running in my network, and decided to monitor all (well, all possible - the QNAP seems to be a problem) devices. That’s quite easy to do by installing Telegraf as a server agent, and add some configuration. Everything is deployed using Ansible, so I can re-use the same Playbook for many devices.

Let’s assume I have a laptop which I want to monitor. The hostname is sunlight (it’s not, I’m just using this as an example).


Add InfluxDB settings in Telegraf using Ansible: [WARNING]: The value [...] (type list) in a string field was converted to "[...]" (type string)

I’m in the process of updating my entire home setup, and integrate everything properly. Part of this process is to automate everything, and use Ansible Playbooks to deploy devices and configurations.


Move InfluxDB data directory to a SDcard

For my openHAB system I installed InfluxDB (on a separate) Raspberry Pi. The Pi has a 32 GB SDcard, but that is not enough for storing all the data, and that Pi has additional work to do as well. For that reason I also attached a 1 TB disk to the Pi, and mounted it on /data. Now all I have to do is move the InfluxDB data directory to /data.