Re: What determines source IP of traffic from OpenBSD box ?

Thank you all for the suggestions, I am currently testing a few of them.

Incase it makes any difference, the underlying problem I have is I have two firewalls with BGP upstreams, one acting as primary, one as standby.  So the problem I am seeing is the age-old problem of asymmetric traffic to the secondary firewall meaning pkg_add on the secondary doesn't work.

I guess I could med/localpref tweak the secondary to push traffic via the primary.  But then I still have the problem of determining return path for the traffic (given inherent overlapping of IP ranges on the boxes).

26 Feb 2021, 15:34 by stu@spacehopper.org:

> On 2021-02-26, Daniel Jakots <danj@chown.me> wrote:
>
>> On Fri, 26 Feb 2021 11:53:40 +0100 (CET), Rachel Roch
>>
> ><rroch@tutanota.de> wrote:
>
>>> Let's say I'm running "pkg_add -u" on a OpenBSD-based router with
>>> multiple interfaces.
>>>
>>> What determines the source IP ?
>>>
>>
>> On -current there is
>> route [-T rtable] sourceaddr [-inet|-inet6] [address]
>> route [-T rtable] sourceaddr [-inet|-inet6] -ifp interface
>>
>
> Use with care though, this can be a footgun (especially if you are
> connecting from there to other local machines with "strict host model").
>
> If you want something more targetted then nat-to is one option.
>