Fedora 40 firms up for release [LWN.net]

Fedora 40 firms up for release

Posted Apr 18, 2024 14:31 UTC (Thu) by Karellen (subscriber, #67644)
Parent article: Fedora 40 firms up for release

I'm kind of surprised that address conflicts are a problem on DHCP-managed address ranges.

Given that DHCP leases tend to be managed by routers, I'd have thought that if a device tries to send an IP packet with a source IP address that is in the DHCP-managed range but was not assigned to it, that the router would either return an error packet to the originator, or just drop the packet on the floor. I would not have expected it to forward the packet to any other devices on the subnet, or to pass it further upstream.

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Fedora 40 firms up for release

Posted Apr 18, 2024 14:42 UTC (Thu) by farnz (subscriber, #17727) [Link]

Most routers route completely separately to DHCP assignment, so there's no knowledge that an IP was manually assigned (or claimed in error) rather than DHCP-managed. Thus, no way to drop packets on the floor if they're from the "wrong" device.

And routers aren't involved at all if the packet is going on the same subnet; packets go direct if you're on the same subnet, and only go via the router if you're going upstream.

Fedora 40 firms up for release

Posted Apr 19, 2024 20:38 UTC (Fri) by mathstuf (subscriber, #69389) [Link]

If this were the case, I'd have a hard time communicating with the router when DHCP is misconfigured (usually my fault) and not doing its job properly. Today, I can claim a static IP, set up routes, and fix my problem over the network.