Re: NAT problems 14.3+

FWIW

Avoiding in-kernel IPFW NAT and using the rc.firewall / type open with =
natd in userspace, nat seems to function fine for my jails.

> On 3 May 2026, at 12:54, Rob Bloemers <[email protected]> wrote:
>=20
> I've tried this setup now on three different machines at three =
different providers, and each time my simple NAT breaks and i'm still =
clueless on the why. And it prevents me from moving quite a few machines =
from 14.3 to newer releases. What works fine on 14.3 breaks on 14.4 or =
newer, which even worse results on 15.0. Even the ipfw nat example from =
the freebsd manual does not work. I'm sure i cant be the only one with =
this issue?
>=20
> Really hope somebody can replicate this for him/herself to confirm =
this and/or give me a solution for my problem.=20
>=20
> Kind Regards
> Rob=20
>=20
>> On 23 Apr 2026, at 12:34, Rob Bloemers <[email protected]> =
wrote:
>>=20
>> had to quickly upgrade to 14.4 again to return to the broken state. =
But unfortunately -tso -lro does not change the result.
>>=20
>> ice0: =
flags=3D1008943<UP,BROADCAST,RUNNING,PROMISC,SIMPLEX,MULTICAST,LOWER_UP> =
metric 0 mtu 9000
>> =
options=3D4e00028<VLAN_MTU,JUMBO_MTU,RXCSUM_IPV6,TXCSUM_IPV6,HWSTATS,MEXTP=
G>
>>=20
>> using
>> ifconfig_ice0=3D"DHCP mtu 9000 -tso -lro -vlanhwtso -vlanhwtag =
-vlanhwfilter"
>>=20
>> Inside the jail, the ISP dns stops responding then too strangely. =
Then when i update it to 1.1.1.1 i can resolve again inside the jail.
>> Then when i ping some domain, the first reply i get is from the =
resolved ip and then i get responses from its own server ip.
>>=20
>> (jail)
>> root@x-mysql:~ # ping nu.nl
>> PING nu.nl (2.16.245.135): 56 data bytes
>> 64 bytes from 2.16.245.135: icmp_seq=3D0 ttl=3D50 time=3D4.603 ms
>> 64 bytes from 57.128.x.y: icmp_seq=3D1 ttl=3D50 time=3D4.588 ms
>> 64 bytes from 57.128.x.y: icmp_seq=3D2 ttl=3D50 time=3D4.602 ms
>> 64 bytes from 57.128.x.y: icmp_seq=3D3 ttl=3D50 time=3D4.602 ms
>>=20
>> Maybe this can be a clue? (i dont remember seeing this before today)
>>=20
>>=20
>>> On 23 Apr 2026, at 10:22, Andrey V. Elsukov <[email protected]> =
wrote:
>>>=20
>>> On 23.04.2026 11:10, Rob Bloemers wrote:
>>>> Yes sir, via ifconfig and using sysctl.conf && fresh reboot. =
Unfortunately no changed.
>>>>>=20
>>>>> Did you try to disable TSO on the ice0 interface?
>>>=20
>>> I'm not sure what you have disabled using sysctl.conf, can you show =
the output of:
>>>=20
>>> ifconfig ice0 | grep options
>>>=20
>>> --=20
>>> WBR, Andrey V. Elsukov
>>>=20
>>>=20
>>=20
>>=20
>=20