• 3 Posts
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Joined 1 year ago
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Cake day: June 12th, 2023

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  • Knowing what and when to abstract can be hard to define precisely. Over abstraction has a cost. So does under abstraction. I have seen, writen and refactored terrible examples of both. Anecdotally, flattening an over abstracted hierarchy feels like less work and usually has better test coverage to validate correctness after refactoring than abstracting under abstracted code (spaghetti code, linear code, brand it how you will). Be aware of both extremes and try to find the balance.


  • My homelab is a 2 node Kubernetes cluster (k3s, raspberry pis), going to scale it up to 4 nodes some day when I want a weekend project.

    Built it to learn Kubernetes while studying for CKA/CKD certification for work where I design, implement and maintain service architectures running in Kubernetes/Openshift environments every day. It’s relatively easy for me to manage Kubernetes for my home lab, but It’s a bit heavy and has a steep learning curve if you are new to it which (understandably) puts people off it I think. Especially for homelab/selfhosting use cases. It’s a very valuable (literally $$$) skill if you are in that enterprise space though.



  • Switched to qbittorrent+gluetun side car recently and it’s been pretty good compared to the poorly maintained combo torrent+OpenVPN images I was using. Being able to update my torrent client image/config independent from the VPN client is great. Unfortunately most of the docs are Docker focused so it’s a bit of trial and error to get it setup in a non-docker environment like Kubernetes. Here’s my deployment in case it’s useful for anyone. Be careful that you configure qbittirrent to use “tun0” as it’s network interface or you will be exposed (got pinged by AT&T before I realized that one). I’m sure there’s a more robust way to makeuse of gluetun’s DNS over TLS and iptables kill switch that doesn’t require messing with qbittorrent config to secure, but that’s what I have so far and it works well enough for now.




  • Not really, its mostly a hobby/nerdy/because I can thing. I am a software engineer with a decade of experience. The job sometimes requires virtual sys admin work (VM/container, cloud networking, etc). Setting up my own baremetal cluster has given me more insight into how things work, especially on the network side. Most of my peers take for granted that traffic gets in or out of a cluster, but I can actually troubleshoot it or design with it in mind.





  • Fyi you will not be able to do live video transcoding with a raspberry pi. I overclocked my pi4’s CPU and GPU and it just can’t handle anything but direct play and maybe audio stream transcoding, though I’ve never had luck with any transcoding period. I either download a format I know can direct play or recently started using tdarr (server on pi, node running on my desktop when I need it) to transcode into a direct play format before it hits my Jellyfin library. Even just using my AMD Ryzen 5 (no GPU) it transcodes like 100x faster than a tdarr node given 2 of the rpi cpu cores. You could probably live transcode with a decent CPU (newer Intel CPUs are apparently very good at it) if you run Jellyfin on the NAS but then you’re at odds with your low power consumption goals. Otherwise rpi Jellyfin is great.

    Good luck, I’d like to build a NAS myself at some point to replace or supplement my Synology.


  • It’s a great tool for knowledge sharing, ramp up and debugging. Definitely not something that needs to happen on every story. Stuck on something or working on a weird bug? Get someone on a call and walk them through it. New team member or old susbsytem not many people understand? Pair the less knowledgeable person up with an SME for the first couple tasks so they can pick the SME’s brain while they work and get valuable context that might be lost in code or the story description.

    It also doesn’t need to drag on. I find 30 minutes is best because as you approach an hour+ attention is hard to maintain. Get on the same page, learn a few things and once your making progress move to async communication.

    Pair programming is a tool and only valuable if you know how and when to use it.


  • Get enough experience and you just have a brief moment of stage 3 as you dive straight to stage 4.

    Unless it’s a customer/that-one-guy-at-work (it’s a title, but there’s usually a handful of them) and then there’s this vast stage 0 of back and forth of “are you sure that’s happening, run these commands and paste the entire output to me” to be sure of what they are saying then you jump to stage 3/4.


  • Measure of a Man was pretty early, season 2 maybe? Pretty sure it was before this one. In any case, yeah I had the same thought. How many times has an organic person been taken over and done something terrible? Picard was a Borg, those weird worm things that infiltrated star trek, those ghosts that take over Troi, O’Brian and Data (again!), etc. Lower Decks has an episode where Merriner thinks Boimler’s girlfriend is too hot for him and spends the entire show trying to figure out what kind of creature she is or alien influence she is under. So yeah, common star trek trope.

    Presumably cooler Star Fleet heads prevailed and realized this situation with Data was no different so he isn’t inherently any more risky than any other sentient being.





  • Generally a hostname based reverse proxy routes requests based on the host header, which some tools let you set. For example, curl:

    curl -H 'Host: my.local.service.com' http://192.168.1.100
    

    here 192.168.1.100 is the LAN IP address of your reverse proxy and my.local.service.com is the service behind the proxy you are trying to reach. This can be helpful for tracking down network routing problems.

    If TLS (https) is in the mix and you care about it being fully secure even locally it can get a little tricky depending on whether the route is pass through (application handles certs) or terminate and reencrypt (reverse proxy handles certs). Most commonly you’ll run into problems with the client not trusting the server because the “hostname” (the LAN IP address when accessing directly) doesn’t match what the certificate says (the DNS name). Lots of ways around that as well, for example adding the service’s LAN IP address to the cert’s subject alternate names (SAN) which feels wrong but it works.

    Personally I just run a little DNS server so I can resolve the various services to their LAN IP addresses and TLS still works properly. You can use your /etc/hosts file for a quick and dirty “DNS server” for your dev machine.


  • So I have jellyfin deployed to my kubernetes home lab, router port forwarded to the ingress controller (essentially a reverse proxy) on the cluster. So exposed to the internet. Everything on it has authentication, either built in to the application or using an oauth proxy. All applications also have valid SSL configurations thanks to the reverse proxy. I also use cloudflare DNS with their proxy enabled to access it and have firewall rules to drop traffic that hits port 80/443 that doesn’t originate from those cloudflare proxy ips (required some scripting to automate). It drops a lot of traffic every day. I have other secuirty measures in place as well, but those are the big ones.

    So yeah, if you expose your router to the internet, its gonna get pinged a lot by bots and someone might try to get in. Using a VPN is a very simple way to do this securely without exposing yourself and I’d suggest going that route unless you know what you’re doing.


  • So a good exercise for threat modeling is to think through what would happen if your instance is compromised. Are there shared passwords on the machine? Other services? Private user data? Etc. Most likely your answer is there is nothing particularly sensitive on your Lemmy machine. If the instance is compromised they just have access to your compute resources at which point they might try to mine crypto with it or something.

    So with that in mind, I might check on your billing model to make sure there isnt any sort of scaling cost they might be able to run up if that happened. Perhaps put some resource usage alarms in place. Im honestly not familiar with Linode, but have a lot of experience with AWS and GCP from my job.

    I also recently found a nice general guide to securing a Linux server on GitHub you might find useful or interesting.