Date: Fri, 2 Feb 2001 09:58:34 -0800 From: Alfred Perlstein <bright@wintelcom.net> To: Peter Wemm <peter@netplex.com.au> Cc: Lars Eggert <larse@ISI.EDU>, freebsd-hackers@FreeBSD.ORG Subject: Re: capturing an early kernel dump Message-ID: <20010202095834.Y26076@fw.wintelcom.net> In-Reply-To: <200102020739.f127dUW23005@mobile.wemm.org>; from peter@netplex.com.au on Thu, Feb 01, 2001 at 11:39:30PM -0800 References: <3A7A3180.35697C0E@isi.edu> <200102020739.f127dUW23005@mobile.wemm.org>
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* Peter Wemm <peter@netplex.com.au> [010201 23:40] wrote: > Lars Eggert wrote: > > > [Repost from last week, no answer then.] > > > > How do I capture an early kernel dump (before rc executes and sets > > dumpdev)? > > > > The dump partition used to be an option in the kernel config file, but that > > seems to have changed in 3.X or 4.X. > > > > Thanks, > > Lars > > How early? We could dump if you were prepared to hardwire in the minor and > major device numbers to get to the devsw[] vectors and manually set the > offsets. > > The biggest problem is that if it is Really Early (TM) we may not have read > the disk label and may not be able to see what the partitions look like. It > may need to be blindly dumped using a magic offset that you supply > somewhere and *hope* that you get the numbers correct so you dont trash > something. > > Alternatively.. dedicate a disk for it and just start dumping to the beginning > of the disk and work upwards... Well, doesn't the loader understand UFS? Why not have it pass the major/minor to the kernel? That way the loader can pass/set the dumpdev pretty safely by looking in /dev. -- -Alfred Perlstein - [bright@wintelcom.net|alfred@freebsd.org] "I have the heart of a child; I keep it in a jar on my desk." To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message
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