• Illecors@lemmy.cafeEnglish
      32·
      1 year ago

      It’s a Class A address, reserved for loopback devices. While not any sort of default - yes, it could be used as home :)

        • Err(()).unwrap()@lemmy.worldM
          1·
          1 year ago

          Technically it fits inside the highest class-A subnet… but I’ve seen so many people (especially teachers) who think that class-A and /8 subnets are equivalent that I firmly believe that the idea of classful networking should be removed from technical literature altogether.

          • azertyfun@sh.itjust.works
            3·
            1 year ago

            Classful IPv4 was obsoleted 32 years ago. Only 8 years left before it’s literally older than a standard career.

            It’s fascinating the sheer inertia that leads formally-trained IT professionals to use and perpetuate such profoundly useless and obsolete nomenclature. You’d think that having an incorrect use of the term “class A” and not having any use for classes B and C would tip off academia that they should cordon off classful networking to the “History of Computing” course next to ARPANET.

            Maybe next time someone refers to 10.0.0.0/8 as a Class A network I’ll refer to it as the ARPANET Network. That’s only very slightly more anachronistic (3 years).

    • Gyroplast@pawb.socialEnglish
      17·
      1 year ago

      Yes. 127.0.0.0/8 is reserved IPv4 address space for Loopback. It is perfectly valid, and occasionally useful, to use other loopback addresses that are functionally identical, like 127.0.1.1 or 127.0.0.53, which carry semantic information for the initiated, like “53? Must be DNS-related, obviously!”

      • kn33@lemmy.worldEnglish
        1·
        1 year ago

        At the place I work, we use 10.127.0.0/16 for loopback addresses on networking equipment because it has that little familiarity from 127.0.0.0/8

  • Gyroplast@pawb.socialEnglish
    11·
    1 year ago

    This reminds me of the tale of the coder tasked to write an input validator for IPv4 addresses. Poor bastard.

    Another fun one: 0177.042.017.066

    PSA: Don’t zero-pad your IPv4 octets. Decimal is for simpletons.

    • toynbee@lemmy.world
      8·
      1 year ago

      These are all network addresses that refer to localhost - how a computer addresses itself.

          • Incogni@lemmy.world
            3·
            1 year ago

            To my limited knowledge: If it ends in .0 it’s the network identifier. If it ends in .255 it’s the broadcast address.

          • ohshit604@sh.itjust.worksEnglish
            1·
            1 year ago

            Why is 255 off limits? What is 127.0.0.0 used for?

            Hypothetically you’re working on an application but you don’t want that application exposed to the internet, you would use localhost to either expose it to 1 machine on your network or network wide by opening a port and telling the application to listen on the private IP assigned by your router.

            Advanced setup would include a reverse proxy to forward the requests from the applications port to the internet, the reverse proxy would use port 80:80 (http) & 443:433 (https), so the flow would look a little like this -

            Internet > Reverse Proxy listening on 80:80 & 443:443 > Application listening on 8080:8080

            —-

            Why does it span to .254? Well this is another advanced setup but if you wanted to segregate two application on different subnets you can. I’m not sure if there is a security benefit by adding the extra hop but the option is there.

      • Possibly linux@lemmy.zipEnglish
        1·
        1 year ago

        Care to explain?

        NAT adds latency plus it makes end to end connections very hard to do. IPv6 on the other hand makes thing much simpler since you don’t need to guess the ports.

        • sharpratchet@lemmy.world
          1·
          1 year ago

          I do a lot of networking and I like being able to remember IPs and subnetting is a lot easier. I haven’t really realized any issues with latency. Haven’t really had to guess ports either as NAT handles that. I think IPv6 is a good idea and works great for computers, but as I human I prefer IPv4.

          • Possibly linux@lemmy.zipEnglish
            1·
            1 year ago

            IPv6 doesn’t need to be hard. For one you can use DNS since it is probably Tue best in terms of readability.

            For addressing you can do a few different things. If you are just looking for simple addresses you can do something like:

            2001:ab6f:c5::5 2001:ab6f:c5::6

            If you have multiple areas or vlans you also can separate them with site info in the address. Something like:

            Site one: 2001:ab6f:1:1::1

            Site two: 2001:ab6f:2:1::1

            Site two vlan 666: 2001:ab6f:2:666::1

            You also can use words like beef and cafe to make it more memorable.

            Ipv6 is also nice since subnetting is much simpler. All subnets are /64 so it is very easy to know if an address is in a subnet. No more /19 and other crazy subnetting madness.