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Joined 1 year ago
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Cake day: July 1st, 2023

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  • I don’t think your question relates to the language as much as to the platform. The language of choice is somewhat irrelevant and what you care about is what actually happens under the hood.

    For the likes of java and go you want to have some understanding of what runtime does for the memory allocations and how their GCs work. For python you sometimes end up in the spots where you need to understand what limitations the GIL imposes (even more important now that they are trying to get rid of it). When you run C (or C++ or Rust) on the embedded hardware it really helps to understand what exactly bit flipping does in specific registers and what DMA means for how you write your code.

    You don’t really have to know it all. You can absolutely write code without caring about anything of that and I know plenty software engineers that do. Some people write amazing functional things in java without ever questioning what it does to the machines and what resources you need to run it.

    If you start questioning it, that will only expand your understanding. It’s not a lateral move from e.g. C to Rust where you need to learn a lot to write your code in a memory-safe way, it’s a movement deeper into the stack and what you learn there will be applicable to any language you use for this stack.

    Answering your question: I always feel bad about not understanding some low-level concept. I have stacks of MCU reference docs lying around, printed, highlighted; I have archives with sample code, and hand-annotated CMSIS reversing notes. Embedded world is hard because you can’t just know C and be done with it. You have to know the hardware, too.

    Here’s my advice for you. Make notes of things that you learn from people smarter than you. Create a web of those notes and see where your gaps are. Then, work on learning something in those gaps in particular and see if you can make a blog post or something of your own. When you share what you learn you become one of those people with deep understanding that others look up to. There’s always someone struggling with something that you either know or know how to figure it out.




  • farcaller@fstab.shtoSelfhosted@lemmy.worldNetwork Switch
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    2 months ago

    I had exactly the same use case and I ended up with a 40G DAC fiber for that case. It ended up cheaper than converting the whole lan to 10G.

    That said, it feels like used 10G equipment is easier to come by than 2.5G for now, and if you have 2G fiber uplink and only 1G past the router then it’s a waste.





  • The biggest certainty is that just having an open port for an SMTP server dangling out there means you will 100% be attacked.

    True.

    Not just sometimes, non-stop.

    True

    So you don’t want to host on a machine with anything else on it, cuz security.

    I don’t think “cuz security” is a proper argument or no one would be ever listening on public internet. Are there risks? Yes.

    So you need a dedicated host for that portion

    Bullshit. You do not need a dedicated host for smtp ingress. It won’t be attacked that much.

    and a very capable and restrictive intrusion detection system (let’s say crowdsec), which is going to take some amount of resources to run, and stop your machine from toppling over.

    That’s not part of the mail pipeline the OP asked for.

    Here, I brought receipts. There are two spikes of attempted connections in the last month, but it’s all negligible traffic.

    Self-hosting mail servers is tricky, same as self-hosting ssh, http, or whatever else. But it’s totally doable even on an aging RPi. No, you don’t need to train expensive spam detection because it’s enough to have very strict rules on where you get mail from and drop 99% of the traffic because it will be compliant. No, you don’t need to run crowdstrike for a server that accepts bytes and stores them for another server (IMAP) to offer them to you. You don’t even need an antivirus, it’s not part of mail hosting, really.

    Instead of bickering and posturing, you could have spent your time better educating OP on the best practices, e.g. like this.


  • farcaller@fstab.shtoSelfhosted@lemmy.worldEmail server thru cloudflare
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    3 months ago

    I won’t quote the bit of your post again, but no, if you have an open smtp port then you won’t get constantly attacked. Again, I have a fully qualified smtp server and it receives about 40 connections per hour (mostly the spam ones). That’s trivial to process.

    It doesn’t matter that I forward emails from another server, because, in the end, mine is still public on the internet.

    If you are trying to make a point that it’s tricky to run a corporate-scale smtp and make sure that end users are protected, then it’s clearly not what the OP was looking for.


  • farcaller@fstab.shtoSelfhosted@lemmy.worldEmail server thru cloudflare
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    3 months ago

    The biggest certainty is that just having an open port for an SMTP server dangling out there means you will 100% be attacked. Not just sometimes, non-stop. So you don’t want to host on a machine with anything else on it, cuz security. So you need a dedicated host for that portion, and a very capable and restrictive intrusion detection system (let’s say crowdsec), which is going to take some amount of resources to run, and stop your machine from toppling over.

    I need to call BS on this. No one cares. I’ve been running a small go-smtp based server that would do some processing on forwarded mail for 2 years now and I don’t see much of “attacks”. Yeah, sometimes I get passersbys trying to figure if this is a mail relay, which it’s not.

    You absolutely don’t need a dedicated machine and an IDS. And you definitely need crowdsec.

    Yeah, sending mail is somewhat hard lately, but DKIM and DMARC can be figured out. Receiving mail is just straightforward.





  • Clearly I mean Garage in here when I write “S3.” It is significantly easier and faster to run hugo deploy and let it talk to Garage, then to figure out where on a remote node the nginx k8s pod has its data PV mounted and scp files into it. Yes, I could automate that. Yes, I could pin the blog’s pod to a single node. Yes, I could use a stable host path for that and use rsync, and I could skip the whole kubernetes insanity for a static html blog.

    But I somewhat enjoy poking the tech and yes, using Garage makes deploys faster and it provides me a stable well-known API endpoint for both data transfers and for serving the content, with very little maintenance required to make it work.




  • I run k3s in my homelab as a single node cluster. I’m very familiar with kubernetes in general, so it’s just easier for me to reason with a control plane.

    Some of the benefits I find useful:

    • ArgoCD set to fire and forget will automatically update software versions as they happen. I use nix to lower the burden of maintaining my chart forks. Sometimes they break, but
    • VictoriaMetrics easily collects all the metrics from everything in the cluster with very little manual tinkering, so I am notified when things break, and
    • zfs-localpv provides in-cluster management for data snapshots, so when things do break I can easily roll back to a known good state.

    k3s is, of course, a memory hog, I’d estimate it and cilium (my CNS of choice) eat up about 2Gb ram and a bit under one core. It’s something you can tune to some extent, though. But then, I can easily do pod routing via VPN and create services that will automatically get a public IP from my endless IPv6 pool and get that address assigned a DNS name in like 10 lines of Yaml.