Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 25 Apr 2002 18:45:28 +0800
From:      "Michael Watson" <watsonmj@toomuch.com.au>
To:        <dan@slightlystrange.org>, <freebsd-questions@FreeBSD.org>
Subject:   RE: Existing Kernel Options
Message-ID:  <000e01c1ec46$5167af60$6401a8c0@intranet.toomuch.com.au>
In-Reply-To: <20020424153315.GB9479@icarus.slightlystrange.org>

next in thread | previous in thread | raw e-mail | index | archive | help
> From: owner-freebsd-questions@FreeBSD.ORG
> [mailto:owner-freebsd-questions@FreeBSD.ORG]On Behalf Of Daniel Bye
> Sent: Wednesday, 24 April 2002 11:33 PM
> To: freebsd-questions@FreeBSD.org
> Subject: Re: Existing Kernel Options
>
>
> On Wed, Apr 24, 2002 at 10:34:52PM +0800, Michael Watson wrote:
> > Hi All
> >
> > I am looking to do my first kernel build, so this may be a
> silly question
> > but hopefully somebody can help.
> >
>
> Excellent!  Get stuck in!  It's easy - ever tried to do a
> kernel rebuild
> under Linux?  I only ever got one to work, and that for only
> 10 minutes
> before locking solid.  That's why I moved to FreeBSD, almost
> three years
> ago, and I have never regretted it.
>
> > I don't think the kernel distributed on my CD-ROM was
> compiled with the same
> > kernel options as in the GENERIC configuration file.  I
> don't want to lose
> > any existing options when I build my new kernel.
> >
>
> I can almost guarantee that the kernel installed when you built the
> system was made from the GENERIC config file.  (Provided you got an
> "official" CDROM, of course...)  If your GENERIC kernel
> config file has
> been edited since, there will be a mismatch.

The kernel I am running from the official distribution CD includes the
firewall (which I can enable using the firewall_enable="YES" option in my
rc.conf file).  The GENRERIC kernel configuration off the same distribution
CD does NOT include the IPFIREWALL option.  The GENERIC file has not been
edited, I have also re-extracted from the CD to make sure.

> > Is there a way to find out what kernel options the existing
> kernel was
> > compiled with?
>
> Not sure - without the file it's hard to say.  Try this, to see if the
> config file was compiled into the finished image (not the case for the
> GENERIC kernel, but it may shed some light):
>
> strings -n 3 /kernel | sed -n 's/^___//p' > MYKERNEL
>
> Then look at MYKERNEL - if there's anything in it, that's the config
> that was used to build your kernel.

I have tried this but to no avail.

> Try building a kernel from the GENERIC file - if it is the
> same size etc
> as your running kernel, you can be fairly certain it was
> built with the
> GENERIC config.

Good idea, I will give this a go.  Although, if they are different I am not
much better off and will end up tring to guess what was different.

> If anyone knows how to "reverse engineer" the kernel to
> reconstruct the
> config file, I would be interested in seeing how...

Me too.

Cheers

Michael


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-questions" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?000e01c1ec46$5167af60$6401a8c0>