Running an Old Kernel

[b. f.]

Martin McCormick wrote:
> I have been attempting to shut off that "last login" message
> that occurs on some FreeBSD systems every time one runs a sudo
> command. I decided to bring back the last kernel which was the
> original Generic kernel from the FreeBSD distribution disk for
> FreeBSD8.0 to see if the problem went away. If it did, that
> would indicate that the problem starts after one applies the
> latest patches and rebuilds the kernel.
>
>         The handbook covers building a new kernel very well, but
> I appear to be missing something. In /boot is loader and
> loader.old. Isn't loader.old the image of the previous kernel? I
> copied loader to loader.new since it should be the current image
> and then copied loader.old to loader and rebooted.
>

I don't think you've read the sections regarding kernel very
carefully.  The loader is built and installed as part of buildworld
and installworld, not buildkernel or installkernel.  It is not the
kernel, which is usually installed in /boot/kernel, with the old
kernel usually being moved to /boot/kernel.old when a new kernel is
installed.

>         The "last login" message was still there and dmesg still
> showed the production date of the new kernel. In other words,
> nothing changed.
>
>         Shouldn't I have seen the production date of the
> original kernel? Thank you.
>
>         I have actually built many kernels and most were simply
> a rebuild of the generic kernel after applying patches so I
> don't roll back a kernel very often. Fortunately, both the old
> and new kernels work. I think the "last login" nuisance started
> right after installing the patched kernel.
>

Why on earth are you tinkering with your kernels in order to change
sudo output?  You should instead be editing configuration files
associated with sudo and related base system utilities, or patching
sudo.

b.