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Cake day: June 17th, 2023

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  • Even if the virtualized router is down, I’ll still have access to the physical server over the network until the DHCP lease expires. The switch does the work of delivering my packets on the LAN, not the router.

    Thanks for the tip about the pfSense limit. After running pfSense for like 8 years, my opinion is that is flush with features but overall, it’s trash. Nobody, not even Netgate, understands how to configure limiters, queues, and QoS properly. The official documentation and all the guides on the internet are all contradictory and wrong. I did loads of testing and it worked somewhat, but never as well as it should have on paper (ie. I got ping spikes if I ran a bandwidth test simultaneously, which shouldn’t happen.) I don’t necessarily think OpenWRT is any better, but I know the Linux kernel has multithreaded PPPOE and I expect some modern basics like SQM to work properly in it.





  • I appreciate the advice. I have like 3 spare routers I can swap in if the server fails, plus I have internet on my phone lol. It’s a home environment, not mission critical. I’m glad you mentioned this though, as it made me realize I should have one of these routers configured and ready-to-go as a backup.

    My logic is partly that I think a VM on an x86 server could potentially be more reliable than some random SBC like a Banana Pi because it’ll be running a mainline kernel with common peripherals, plus I can have RAID and ECC, etc (better hardware). I just don’t fully buy the “separation of concerns” argument because you can always use that against VMs, and the argument for VMs is cost effectiveness via better utilization of hardware. At home, it can also mean spending money on better hardware instead of redundant hardware (why do I need another Linux box?).

    There are also risks involved in running your firewall on the same host as all your other VM’s

    I don’t follow. It’s isolated via a dedicated bridge adapter on the host, which is not shared with other VMs. Further, WAN traffic is also isolated by a VLAN, which only the router VM is configured for.








  • How are the alternatives any better? Download a DEB that executes arbitrary code, signed with some .asc that’s sitting in the same webserver? Download an EXE?

    Your comment is so rambley that I can’t understand whether you’re criticizing the distribution method or the packaging. Both of those are very different in terms of attack surface, if you’re talking about supply chain attacks.




  • GameGod@lemmy.catoSelfhosted@lemmy.worldHave I been DoS'd?
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    2 years ago

    I don’t see anyone else actually telling you how to figure out if you’re being DoSed, so I’ll start:

    Check your logs. Look at what process is eating your CPU in htop and then look at the logs for that process. If it’s a web application, that means the error and access logs for it. If you see a flood of requests to a single URL, or some other suspicious pattern in the log, then you can try blocking the IPs associated with them temporarily and see if it alleviates the load. Repeat until the load goes down.

    If your application uses a database, check your database logs too. IIRC postgres logs queries that take longer than 5 seconds by default, which can make it easy to spot a slow query especially during a time of high load.

    I don’t think DNS amplification attacks over UDP are likely to be a problem as I think most cloud providers filter traffic with forged src addresses (correct me if I’m wrong). You can also try blocking all inbound UDP traffic if you suspect a UDP flood but this will likely break DNS lookups for you temporarily. (your machine should not have any open UDP ports in any case though if you’re just running Lemmy).

    If you want to go next level, you can use “perf” to generate a system-wide profile and flamegraph which will show you where you’re burning CPU cycles. This can be extremely useful for troubleshooting performance or optimizing applications. (you’ll find that even ipfilters takes CPU power, which is why most DDoS protection happens on dedicated hardware upstream)