I have an Ansible playbook I run each weekend to do all the apt updates. As well as keeping everything up to date, it’s a good check-in that everything’s alive and working as expected. I have Uptime Kuma checking the services are alive, and that no one is running out of disk or memory so there shouldn’t be any drama right?
This weekend, three instances (two remote, one local) timed out with “unreachable”.
I’ve taken to running lots of my services in LXC containers under Proxmox. I like the feeling of installing in a VM, but it’s lightweight. I like the backups, I like things being isolated from each other, I like moving them around between machines easily. I’m just a big LXC lover at the moment.
I’m also a Tailscale lover, and the generous number of nodes in the free tier means I now just routinely install them in my VMs and containers without a thought.
I’ve picked up an new TP-Link WAP with Omada, so I wanted to spin up an Ubuntu 20.04 LXC to run the controller software in, and ended up spending a couple of hours figuring out why things where not working.
The initial problem was I was having connectivity issues pulling down the updates for all the packages required. I went down a bit of a tangent because I installed an apt cache the other day, so I was looking for problems there. Eventually I narrowed it down to DNS not working and started A/B testing like this:
I’m normally a x.1 release type of sysadmin, but the increasing temptation of installing Proxmox 8.0 while I’ve got some time off, and the fact that I’ve got a cluster, so I can just move the VM’s around all adds up to thinking I’ll do that today.
Here’s how my system works. It consists of three HP-800 mini G2’s. pve-prod1 is a bit fancier - i7 6700T and 32GB, the other two are i5 6500T and 16GB. The production VM’s use the local SSD but backups go to the NAS. All the machines are currently running Proxmox 7.4. They are not clustered in the proper sense - I don’t need high availability, and I don’t want to run them all the time. pve-prod1 runs 24/7 and I just power up pve-dev1 when I’m working on something.