Re: backward compatibility: how far can it reasonably go?

[Brad Spencer <brad%anduin.eldar.org@localhost>]

"Greg A. Woods" <woods%planix.ca@localhost> writes:

> So I've got a couple of old but important machines (Xen amd64 domUs)
> running NetBSD-5, and I've finally decided that I'm reasonably well
> enough prepared to try upgrading them.
>
> However it seems a "modern" (9.99.81, -current from about 2021-03-10)
> kernel with COMPAT_40 isn't able to run some of the userland on those
> systems.
>
> Is this something that should work?
>
> If it should I think it would make the upgrade much easier as I could
> then plop down the new userland and run etcupdate.  (there are of course
> alternative ways to do the upgrade, eased by the fact they are domUs (*))
>
> The most immediate problems I noticed are with networking.  ifconfig -a
> returns without printing anything, and trying to enable IPF crashes:


When I took a system from 4.0 to 7.x some time ago, the only thing that
I had problems with was anything that used scheduler activations since
that had been removed.  For me this only effected stuff from pkgsrc, as
I also rolled in new userland at the same time.




-- 
Brad Spencer - brad%anduin.eldar.org@localhost - KC8VKS - http://anduin.eldar.org