Re: dhcpcd(8) into FreeBSD base

I have tried the "noip4ll" and "noarp" option. Didn't change anything.

My issue ended up that dhcpcd said in the logs it would sent a dhcp packet (the port 67/68 thing), but nothing appeared on the network. And so the lease timed out after a long time and it removed the IP address from the interface.

Ronald.

 
Van: Karl Denninger <karl@denninger.net>
Datum:vrijdag, 20 juni 2025 15:24
Aan:freebsd-net@freebsd.org
Onderwerp:Re: dhcpcd(8) into FreeBSD base
> 
> On 6/19/2025 04:21, Ronald Klop wrote:
>> Hi,
>> 
>> I don't know the details about your setup, but I tried dhcpcd in my network last few months and I encountered that it:
>> 
>> - runs fine in a 14.X jail on a 14.X machine (RPI3B) for both IP4 and IP6
>> - it does not work well on a 14.X jail on a 15.x machines. (RPI4)
>> 
>> The symptoms look a lot like what you describe. Sometimes it got an address and a day later it was gone again. Restarting sometimes helped, often didn't change anything.
>> Up to the point that I started reading to code of dhcpcd and encountered that it writes a line in the log about getting a lease and the next statement was sending a packet out on the network and I never see that packet in tcpdump.
>> 
>> Anyway on the RPI3 I still use it. On the RPI4 I went back to dhclient + SLAAC after I put a lot of time in tcpdumping and testing. Maybe it is just that 14 userland doesn't match enough with 15 kernel to do BPF/dhcp. But than again.... with dhclient it works fine.
>> 
>> I didn't run dhcpcd yet on the host OS yet as I was first testing it in the VNET jails.
>> 
>> Just my 2 cents.
>> 
>> Regards,
>> Ronald.
>>  > 
> Now that's very curious.
> 
> Could you (where you can control what's going on with the other end, which I can't) try again with "noip4ll" and "noarp" and see if you still get the oddness?
> 
> I have a suspicion this is the cause (from the docs "noarp" should be enough to disable both, but never hurts to stick 'em both in there) -- and if so then perhaps default behavior should be changed.
> 
> --
> Karl Denninger
> karl@denninger.net
> The Market Ticker
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>