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  • 30 Comments
Joined 3 years ago
Cake day: June 9th, 2023
  • lungdart@lemmy.catoLinux@lemmy.ml•(RESOLVED) Network is slow after installing Fedora
    42·
    1 year ago

    Here’s my testing recommendations

    Testing methodology

    To get consistant results, use a consistent method of test. If you’re downloading a large file, always test by downloading that same file from that same source. If you’re using a speed test service, use the same speed test service with the same server. If you’re using a tool like iperf3, always use the same tool against the same iperf server.

    Potential issues

    Networks can fail from hardware issues, software issues and infrastructure issues. Since you don’t control 99.9% of the infrastructure if the internet is involved, lets leave that for the last option.

    Hardware Issues

    The hardware involved you control are mostly your NIC, and your Remote Connection. For wired ethernet at home, this is likely a physical ethernet port on your computer on one end, and another physical ethernet port on a switch/router/ap provided by your ISP.

    Testing Wired Hardware Issues

    • Using the same switch and cable, run a speed test on another computer. If the issue persists, the problem is not with your computer, if it resolves, its related to your computer.
    • Using the same computer and cable, run a speed test on another switch. If the issue persists, its not the switch or cable, its your computer, if it resolves, its not your computer.
    • Using the same computer and switch, use a different cable. If the issue persists, it’s not the cable and its either your computer or switch, if it resolves, its the cable.

    With these three you can figure out what device is causing the problem.

    Testing Wireless Hardware Issues

    The hardware involved is the wireless NIC in your computer, the environment your wifi signal is in, and the wifi AP. The steps are much the same as testing for a wired issue

    • Using the same AP and physical location, run a speed test on another computer. If the issue persists, the problem is with the AP or location, if it doesn’t it may be your computer
    • Using the same computer and physical location, run a speed test on another AP. if the issue persists, the problem is with your computer or location, if it resolves, it may be the AP
    • Using the same computer and AP, run a speed test in another physical location. If the issue persists, the problem is with the computer or AP, if it resolves it may be the environment

    Software Issues

    The issue could be software related. Something like the drivers running on your laptop or connection point.

    Testing Computer Drivers

    You’ve already done this for your computer by dual booting. This proves the issue is not driver related, since the problem persists with two different sets of drivers.

    Testing Connection Point Drivers

    • You have less control over the drivers on your switch/router/ap. If the hardware tests resolve when using a different AP, then you can attempt a firmware upgrade/downgrade before replacing the physical device. This isn’t usually worth the hassle since ISPs are quick to replace them with a service call.

    Testing Computer Configuration

    Your network settings could be misconfigured.

    • If you are using DHCP, turn it off, and enforce a speed negotiation, IP address, subnet mask, and DNS server and try again. If the issue persists, then it’s likely not related to your configuration. If it resolves it probably is.
    • If you are using a static configuration, turn it off and use DHCP. If the issue persists, it’s likely not related to your configuration, if it resolves, it probably is

    Infrastructure Issues

    If your home network is more sophisticated then an ISP provded router/switch/ap combo connected to everything over wifi and ethernet, theres more devices to troubleshoot. But if you have something like this, you probably already know what you’re doing a little bit and wouldn’t be making this post. But who knows! Re-run the process isolating each device and replacing it with something known good to identify whats causing the problem.

    As for the internet, it’s not a stable and safe place. Speeds vary drastically day to day. Internet weather happens and partial outages occur regularly. Don’t forget that the service your using to speed test could be the issue itself. It’s another component to isolate and test.

    Process

    Use the above steps to identify what device is causing the problem, and if its a hardware or software issue. Hardware issues are mostly resolved by replacing devices, while software issues are resolved with software updates and configuration changes.

    Good luck and god speed!

  • lungdart@lemmy.catoLinux@lemmy.ml•BSD Vs. Linux
    1·
    2 years ago

    The majority of the Internet’s routing and switching architecture is BSD based. Historically it had the most stable and performant network stack of all the OSs.

    I used it extensively at one job in a previous life when I was a network appliance developer. It was rock solid and lightning fast. Tried it as a desktop at home and had a terrible experience.

    The little differences in the Unix commands used to drive me nuts as well…

  • lungdart@lemmy.catoSelfhosted@lemmy.world•Another good reason not to open port 22English
    201·
    3 years ago

    Moving the port doesn’t reduce attack surface. It’s the same amount of surface.

    Tailscale is a bit controversial because it requires a 3rd party to validate connections, a 3rd party that is a large target for threat actors, and is reliant on profitability to stay online.

    I would recommend a client VPN like wireguard, or SSH being validated using signed keys against a certificate authority your control, with fail2ban.

  • lungdart@lemmy.catoSelfhosted@lemmy.world•Have I been DoS'd?English
    25·
    3 years ago

    Sounds like you were out of resources. That is the goal of a DoS attack, but you’d need connection logs to detect if that was the case.

    DDoS attacks are very tricky to defend. (Source: I work in DDoS defence). There’s two sections to defense, detection and mitigation.

    Detection is very easy, just look at packets. A very common DDoS attack uses UDP services to amplify your request to a bigger response, but then spoof your src ip to the target. So large amounts of traffic is likely an attack, out of band udp traffic is likely an attack. And large amount of inband traffic could be an attack.

    Mitigation is trickier. You need something that can handle a massive amount of packet inspection and black holing. That’s done serious hardware. A script kiddie can buy a 20Gbe/1mpps attack with their moms credit card very easily.

    Your defence options are a little limited. If your cloud provider has WAF, use it. You may be able to get rules that block common botnets. Cloudflare is another decent option, they’ll man in the middle your services, and run detection and mitigation on all traffic. They also have a decent WAF.

    Best of luck!