Now that we have our foundation laid with a fresh installation of Debian and Organizr, we can now move on to the data collection portion of our dashboard.  After all, we have to get the stats about our homelab before we can make them into pretty pictures.  Before we can go get the stats, we need a place to put them.  For this, we’ll be using the open source application InfluxDB.  Before we dive in, let’s take a at the series so far:

1. An Introduction
2. Organizr
3. Organizr Continued
4. InfluxDB
5. Telegraf Introduction
6. Grafana Introduction
7. pfSense
8. FreeNAS

What is InfluxDB?

In part 1 of this series, I gave a brief overview of InfluxDB, but let’s dig a little deeper.  At the very basic level, InfluxDB is a time-series database for storing events and statistics.  The coolest part about InfluxDB is the HTTP interface that allows virtually anything to write to it.  Over the next several posts we’ll see Telegraf, PowerShell, and Curl as potential clients to write back to InfluxDB.  You can download InfluxDB directly from GitHub where it is updated very frequently.  It supports authentication with multiple users and levels of security and of course multiple databases.

Installing InfluxDB

Installing InfluxDB is a pretty easy operation.  We’ll start by logging into our Linux box using PuTTY:

 

We’ll issue this command (be sure to check here for the latest download link):

sudo wget https://dl.influxdata.com/influxdb/releases/influxdb_1.5.4_amd64.deb
sudo dpkg -i influxdb_1.5.4_amd64.deb

The download and installation should look something like this:

Almost too easy, right?  I think that’s the point!  InfluxDB is meant to be completely dependency free.  Let’s make sure everything really worked by enabling the service, starting the service, and checking the status of the service:

sudo systemctl enable influxdb
sudo systemctl start influxdb
systemctl status influxdb

If all went well, we should see that the service is active and running:

 

Configuring InfluxDB

We’ll stay in PuTTY to complete much of our configuration.  Start influx:

influx

This should start up our command line interface for InfluxDB:

Authentication

By default, InfluxDB does not require authentication.  So let’s fix that by first creating an admin account so that we can enable authentication:

CREATE USER "influxadmin" WITH PASSWORD 'influxadminpassword' WITH ALL PRIVILEGES
exit

You’ll notice that it isn’t terribly verbose:

Once we have our user created, we should be ready to enable authentication.  Let’s fire up nano and modify the configuration file:

 sudo nano /etc/influxdb/influxdb.conf

Scroll through the file until you find the [http] section and set auth-enabled to true:

Write out the file with control-o and exit with control-x and you should be ready to restart the service:

sudo systemctl restart influxdb

Now we can log back in using our newly created username and password to make sure that things work:

Create Databases

The final steps are to create a few databases finally a user to access them.  You can just use the admin use you created, but generally its better to have a non-admin account:

CREATE DATABASE "TelegrafStats"
CREATE DATABASE "vmWareStats"
CREATE DATABASE "PowerShellStats"

I created three databases for my setup.  One for use with Telegraf, one to store various vmWare specific metrics, and one for all of the random stuff I like to do with PowerShell.  All of these will get their own set of blog posts in time.

Grant Permissions

Finally, we can create our user or users and grant access to the newly created databases:

CREATE USER "influxuser" WITH PASSWORD 'influxuserpassword'
GRANT ALL ON "TelegrafStats" TO "influxuser"
GRANT ALL ON "vmWareStats" TO "influxuser"
GRANT ALL ON "PowerShellStats" TO "influxuser"

Again…not terribly verbose:

 

Retention

By default, when you create a database in InfluxDB, it sets the retention to infinite.  For me, being a digital packrat, this is exactly what I want.  So I’m going to leave my configuration alone.  But…for everyone else, you can find a guide on retention and downsampling here in the official InfluxDB documention.  You can find the specific command details here.

Conclusion

That’s it!  InfluxDB is now ready to receive information.  In our next post, we’ll move on to Telegraf so that we can start sending it some data!

Version Update

When this blog post was written, InfluxDB 1.5.4 was the latest release.  Before I was able to publish this blog post, InfluxDB 1.6 was released.  Feel free to install that version instead of the version above:

sudo wget https://dl.influxdata.com/influxdb/releases/influxdb_1.6.0_amd64.deb
sudo dpkg -i influxdb_1.6.0_amd64.deb