Yep, ive seen it all!

Not causing a nuisance. It’s the range used when a DHCP server is not available and the client is using dynamic addressing. It’s less efficient because the client has to check that the address isn’t in use, which could involve several queries.

Generally, if you get a link-local address it indicates something wrong with your network.

It doesn’t really matter as long as you run a DNS server. Which also makes IPv6 addresses just as useable.

In reply to a post by TinyMongomery:

Not causing a nuisance. It’s the range used when a DHCP server is not available and the client is using dynamic addressing. It’s less efficient because the client has to check that the address isn’t in use, which could involve several queries.

Generally, if you get a link-local address it indicates something wrong with your network.

LOL, this was probably 20 years ago and I forget the exact circumstances. Probably hybrid 16 and 32 bit Windows. I think the issue was that I was trying to run NetBIOS over TCPIP networking with OS/2 and the wretched Windows machines would revert to native NetBIOS and put themselves on Link-local TCPIP. To me, this passed the threshold for being a nuisance

Edited by DFScale (Wed 10-Apr-24 20:47:46)

OS/2 was always better at communications than Windows. Especially when it came to talking to big iron. But it could be a little tricky to configure.

I miss OS/2; it was rock solid and incorporated some novel ideas. But all things must pass.

For me, 192.168.0.0/23 (private LAN), 192.168.16.0/23 (restricted internet access)

There's a bit of practicality about this. I was using 192.168.1.0/24 for both DHCP and static reservations and was running out of addresses. I extended the subnet, shifted DHCP to 192.168.0.1-250, which gave me a whole load of extra spaces and then re-addressed all of the static stuff, most of it remaining where it was in 192.168.1.x, but gave it a new netmask. My gateway was always 192.168.1.254, so nothing broke while I did this. The restricted subnet has the same setup, with half DHCP and half static address reservations.

I wouldn't bother using 10.x.x.x (or 172.16.x.x - 172.31.x.x) personally - too much conflict with work stuff and if you use VPNs for remote access, this might cause you some issues down the road. Easier to avoid and for most people, there's no shortage of capacity in the 192.168.x.x, which tends to be rarely used in the corporate world.

Will shove in a new subnet for guests when I get around to upgrading my wifi to something that supports multiple SSIDs / VLANs, but I'm refusing to do this until I get my flippin' fibre installed (anywhere between now and the heat-death of the universe).

In reply to a post by jchamier:

Corporately we used to interopeate with thousands of customers, network's connected (and lots of firewall rules at each end!). A client that had 10.x.x.x had to be NAT'd to somewhere in our IP space, absolute pain in the ....

Going back 25 years, my old company owned 3.0.0.0/8 and every PC globally had a 3.x.x.x address. Ironically, for security reasons they didn't even have this network publicly routable, so your connection to the internet was nat'ed through a more conventional address, which was utterly insane when you think of it.

At some point after I stopped working for them, they re-addressed their global network to 10.x.x.x and sold 3.0.0.0/8 for what I presume was a king's ransom!

edit: Just checked and they sold it to Amazon who presumably use it for AWS. King's ransom is probably a bit of an understatement there

Edited by daern (Mon 29-Apr-24 18:29:55)

In reply to a post by daern:

Going back 25 years, my old company owned 3.0.0.0/8 and every PC globally had a 3.x.x.x address. Ironically, for security reasons they didn't even have this network publicly routable, so your connection to the internet was nat'ed through a more conventional address, which was utterly insane when you think of it.

At some point after I stopped working for them, they re-addressed their global network to 10.x.x.x and sold 3.0.0.0/8 for what I presume was a king's ransom!

edit: Just checked and they sold it to Amazon who presumably use it for AWS. King's ransom is probably a bit of an understatement there

Ah GE! Amazon got a volume discount