Recently I got the itch to learn something new and I chose to explore Grafana. Of course, I needed something to graph or make a dashboard out of. So I pondered for a while and during that time I had some trouble with my internet connection. This of course had me looking at my cable modem stats page and that’s where I found my inspiration. So many numbers that are a point in time snapshot that I wished I had a historical graph of. So I set about figuring out how to install Grafana in docker and pull the data in. I quickly found that grafana is a display thing and not a collector and display. This meant that I had to collect the data and store it so that grafana could display it. For this, I figured I could store it in MariaDB, as using that in grafana looked simple enough. The problem I had was getting the data off of the modems stats page. I plinked around with a bash script and a python script, neither did that great for me. About this time I remembered that nodered has some power to it and tried that. I managed to pull the data and store it into MariaDB via nodered. I then managed to display the data via grafana and was rather satisfied with myself.

I ran into an issue re-enabling SELinux on my little fleet of CentOS 7 boxes in my home lab. Basically when I installed them I had disabled SELinux at install and thus enabling SELinux was causing all the systems to freeze up after a reboot.

Here is a bonus post. I am not going to go into deep details but should be enough to give a good idea on how to do this.

At this point if everything works you should be able to ping between the networks. If that isn’t working then you need to troubleshoot what is breaking down communication wise. This could be anything from the two local routers not sharing routes to the routers not talking over zerotier. The point I am trying to push across is that there is no simple gotchas I can offer troubleshooting steps for.

So I have gone a little crazy lately in my home lab. I have created a anycast address in the LAN of 10.10.10.10 that goes to the nearest pihole. (Local, Datacetner 1 or Datacenter 2) While that was nice I still wanted a way to have pihole while on the go. I thought about a VPN, that works but is not perfect for what I want. A little more pondering and I found that Android 9 supports “Private DNS”. Turns out that it is a simply DNS over TLS. (DoT) That just makes this so much easier now.

With the VM building out of the way, on to configuring the VMs.

To bring us into part 2, the next thing is to create the routing VMs.