I love that people forget about 127.0.0.0/8 being the loopback network. Everyone just uses .1 when there are so many to choose from.
this post was submitted on 04 Nov 2026
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People also commonly do not know that the reserved for intranet ip address range of 192.168.0.0 is actually /16 so you can pick any number between 0 and 255 for that 3rd byte and have their whole network in a range other that 192.168.0.0/8 like pretty much everybody else.
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IPv6: Fuck you, you're only allowed one, now. Yeah, yeah, I know there are about 340 undecillion addresses in the space, but I know better than you, no one in history has ever needed to bind different services to the same port on the loopback interface, and if they did they were doing it wrong. Oh you made an RFC draft? Well I let the one from ~~2015~~ 2012 expire, so good luck with your current proposal, pleb.
Can't you just use a ULA address for that?
So the onus is on every individual user, to pick a random ULA prefix, bind specific addresses from it to the loopback interface, which is a different procedure for different OSes, probably requires root or elevated privileges, can have hard limits on, document it, etc. Greeeeaaaaaaat design. IPv6 gives out /64 like they're about to turn bad, but can't spare a /104? Gimme a break.
I can dig a hole with a spoon, too, but if someone made it so that no one was allowed to dig holes with shovels unless they build their own (and have permission to build the shovel), when previously everyone was allowed to dig with shovels, I would not think highly of that person's wisdom.
Maybe you think G. Huston of APNIC and W. Kumari of Google don't really know what they're talking about?
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Gateway is .69
Dhcp is .70 - .254
Static routes are .68 and below
I will not be taking any questions
About twenty years ago I was hired in to straighten up a network at a investment place. They were running all static IP addresses and the guy who set it up set the gateway to 69. I laughed and started converting them to dhcp and seriously considered leaving the gateway alone.
I have to ask a question now. My question is, is that you?
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10.0.0.0/8 address space with a gateway address that gets randomized every 24 hours. Tomorrow's address is advertised on a HTTP server local to the network that cannot be externally accessed. For security reasons.
Thatβs the kind of overengineering I was hoping for!
Nothing advertises hostnames, and the DHCP table is dumped and every client gets new address at the same time, too.
Just make sure the MAC addresses randomize, too, and then you've got yourself a proper fucking mess for a hacker to sort out.
the honeypot house of mirrors
Throw in some random static DHCP leases that cycle every hour and update the firewall rule alias
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There's nothing preventing the gateway from being a DHCP client, just saying..
Settle down, Satan.
oh my god
i love this idea so much. I've been doing networking for 13 years now and I've never considered a dynamically addressed gateway
At first I didn't understand then I read your comment... oh, my, god!
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your home router is a DHCP client of your ISP's DHCP server, so...yea.
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It's good to be reminded that some things are just conventions rather than hard rules. I forget things like that (if I ever knew them to begin with).
On topic, I usually do 192.168.0.1 or 192.168.1.1 depending on the situation.
Meanwhile my gateway is fe80::17a9:3ba7:5Β₯4π:b8Γ€7%42
Wait is there an existing unicode to ipv6 method. I assume it would just be the bit values of the emoji in utf8?
fe80::"hello π" aka fe80::6865:6c6c:6f20:f09f:9094
I approve of the idea of cursed ipv6 notation.
That would be a funny way to avoid DNS, just make the address the name.
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IP addresses are one thing, but wtf is a subnet mask??
Wtf is 255.255.255.255 and why does it keep showing up???
If a bit in those 4 bytes is 1 that means that the same bit in the IP address is part of what defines the network whilst the bits that are 0 are bits that can change in the IP address and that machine will still be part of that sub-network.
So a mask of 255.255.252.0 (notice the 3rd byte) on a network with a prefix 192.168.0.0 means that 192.168.0.20 is in that sub-network AND 192.168.2.20 is part of that sub-network too, because the two lowest bits of the 3rd byte in that mask are 0, meaning that IP address where those bits vary are still in the same sub-network (i.e. the ranges 192.168.0.XXX, 192.168.1.XXX, 192.168.2.XXX and 192.168.3.XXX are all in the same sub-network).
If instead the sub-network prefix was the same 192.168.0.0 but with a mask of 255.255.255.0 (the most common case you find in home internal networks) then 192.168.2.20 would NOT be part of the same sub-network as 192.168.0.20
You probably also see now why a network mask is needed alongside the network prefix - in both examples above 192.168.0.0 is the network prefix, but without the network mask you don't know which 0 bits in that network code can be changed to make an IP address still in the same sub-network.
Note that you can change the mask to make the sub-network smaller as well as to make them bigger: for example 192.168.0.0/255.255.255.223 is a perfectly valid subnetwork that fits 30 machines.
See chronicledmonocle@lemmy.world 's post for a full explanation.
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It tells you how to read the IP address. Itβs a really cool trick thatβs an enormous pain in the ass.
If you're serious, you can't have one without the other.
Why can't you have ip addresses without subnet masks? Couldn't the whole internet be on a single network? Would be horrible for a number of reasons, but everything could still work.
Your question is already answered here, but it also reduces traffic by keeping packets within a network defined by the subnet mask. It establishes guardrails so packet broadcasts aren't sent everywhere. The Internet is a single network. But not all of it can communicate with other parts without the right access permissions. Subnet masks are one very basic aspect of that access control.
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It is about security.
So you can differentiate between the outside network and the local network. And even divide 2 local networks as well.
Would it be possible? Sure. Just like it would be possible to have no speed limits for cars.
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Last address? Who the heck does that???
I've had modems from my ISP which assigned themselves 192.168.0.254 for some reason. I have no idea why
My guess is that enough people were buying routers and using them as access points. They all tend to be on 192.168.0.1 .254 means you don't get as bad collisions when that happens. It would cut down on technical support calls.
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My home server is at 192.168.1.230 because that's what IP was assigned to the machine at the moment I set it up.
Yep. Love that chaos, ya know?
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