Subnet Mask

374 points · 34 comments · view on lemmy.world

34 Comments

possiblylinux127@lemmy.zip · 23 pts · 4d (2 replies)

Just use IPV6

kn33@lemmy.world · 16 pts · 4d

/64

Kangae_Hishiryo@scribe.disroot.org · 2 pts · 3d

Network prefix length/CIDR notation: ( ͡° ͜ʖ ͡° )

in_my_honest_opinion@piefed.social · 22 pts · 4d (6 replies)

That's way too broad, for protection it should probably be 255.255.255.254

giacomo@lemmy.dbzer0.com · 15 pts · 4d (4 replies)

255.255.255.252 for your significant other

somenonewho@feddit.org · 4 pts · 4d (1 reply)

I don't need a gateway or broadcast to talk to my SO just .0 for me and .1 for them

kn33@lemmy.world · 2 pts · 3d

Yeah but then you don't have ARP and you gotta set in the MAC manually and that just seems like a hassle.

libewa@feddit.org · 1 pts · 3d (1 reply)

I think you both have an off-by-one error there. It‘s /32 for one device and /31 for 2 devices (selected by the last bit). It feels wrong to have /32 be the entire adress space btw.

in_my_honest_opinion@piefed.social · 1 pts · 2d

/32 is often used in static IP networks that face the public, I do it with direct point to point VPNs all the time.

G_M0N3Y_2503@lemmy.zip · 1 pts · 3d

at least N95!

comador@lemmy.world · 21 pts · 4d (3 replies)

Momma I'm comin' 127.0.0.1

nonentity@sh.itjust.works · 7 pts · 3d

Home is ~, localhost is wherever you are.

Kangae_Hishiryo@scribe.disroot.org · 2 pts · 3d

God: I'm 0.0.0.0/::1

dbtng@eviltoast.org · 1 pts · 3d

0111111.00000000.00000000.00000001
But I doubt your momma can read that.
Mine can't. She's not interested in binary or hex, despite my efforts to convince her how fascinating the topic is.

fistac0rpse@fedia.io · 14 pts · 4d (2 replies)

how is this a Linux meme?

giacomo@lemmy.dbzer0.com · 18 pts · 4d

its hardly even a meme.

itrealgood@mander.xyz · 10 pts · 4d
[ removed ]
xia@lemmy.ca · 13 pts · 4d

A subnet mask mask!

undefined@lemmy.hogru.ch · 6 pts · 4d (13 replies)

Could we have an IPv6 one? It’s 2026.

HeyJoe@lemmy.world · 4 pts · 4d (11 replies)

But it's not possible to do this joke since ipv6 does not have subnets.

undefined@lemmy.hogru.ch · 2 pts · 4d (6 replies)

/24

libewa@feddit.org · 3 pts · 3d (5 replies)

/128

dbtng@eviltoast.org · 0 pts · 3d (4 replies)

um ... that's wrong.

libewa@feddit.org · 3 pts · 3d (3 replies)

why?

dbtng@eviltoast.org · 2 pts · 3d (2 replies)

Two reasons.

You were responding to someone who offered a /24 as a subnet.
There are 32 bits in an IPv4 address. /24 is 255.255.255.0.
So they were wrong too in reference to IPv6, but at least they were making sense.
You responded with /128, which is the full range of the IPv6 address.
That would be like the prior poster saying /32 aka 255.255.255.255.
There's no usable range there.

And, see my post above for the rest of the breakdown, but you were looking for /64.

libewa@feddit.org · 1 pts · 3d

But the mask is a firewall to prevent viruses from leaving or reaching you, so a firewall on ::1/128

offspec@lemmy.world · 2 pts · 3d (2 replies)

What? There's no way that's right, right?

dbtng@eviltoast.org · 2 pts · 3d

Well, sort of.
You can divide up IPv6 addresses as you like.
But ... there's so much space there that they are typically just divided in half.
64 bits of subnet (aka routing prefix) + 64 bits of host address.
They play a lot of games with the first 12 or so bits to say what kind of network it is, and the rules change a lot for multicast and other address types.
So its not a subnet as you know it, but it still is.

kinther@lemmy.world · 1 pts · 3d

You could interpret it that way, sure. There are so many IPv6 addresses you really don't have to subnet anything like you did in IPv4. The typically "mask" you will see is a /64.

Kangae_Hishiryo@scribe.disroot.org · 1 pts · 3d

There's no subnets, but there are network length prefixes/CIDR

dbtng@eviltoast.org · 2 pts · 3d

no.

kinther@lemmy.world · 5 pts · 3d (1 reply)

For more fun IPv6 knowledge, Hurricane Electric provides a certification course! You also get a t-shirt when you finish it.

https://ipv6.he.net/certification/

dbtng@eviltoast.org · 1 pts · 3d

That's pretty cool. I crammed to pass the CCNA, and some of its fading from my head now. I could use a refresher. Thanks!

LemmyBruceLeeMarvin@lemmy.ml · 2 pts · 4d

I'll get your coat