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MrDOS • yesterday at 5:10 PM • 1 reply • view on HN

There's gotta be a bit more subtlety going on here. DHCP leases include a lifetime:

    $ ip address show dev br0 | grep -m 1 valid_lft
           valid_lft 69133sec preferred_lft 69133sec
It's possible that older versions of macOS persisted the lease details across reboots and reused unexpired leases on subsequent network reconnections.

I am also fairly sure that I have never personally seen any evidence of any OS doing this, including macOS, including when it was still called Mac OS X. I suspect macOS simply brings up its networking stack earlier in the boot process, so the network connection is more likely to be ready and waiting by the time the desktop loads.

Replies

akdev1l • yesterday at 8:15 PM

Using the same lease is better but still could cause IP conflict if the lease was revoked and reused (though I guess that’s much rarer)

that said I do agree with you that the behaviour was probably not as described or at least not present in current systems because it would wreak havoc on public wifi etc

I’ve never dhcp being any sort of bottleneck so I hope their just doing the regular dhcp thing