Date: Fri, 17 Oct 1997 09:40:07 -0700 (PDT) From: Doug White <dwhite@gdi.uoregon.edu> To: lamaster@george.arc.nasa.gov Cc: freebsd-questions@FreeBSD.ORG Subject: Re: Cannot mount / Message-ID: <Pine.BSF.3.96.971017093511.3521C-100000@gdi.uoregon.edu> In-Reply-To: <199710161909.MAA18901@george.arc.nasa.gov>
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On Thu, 16 Oct 1997 lamaster@george.arc.nasa.gov wrote: > A) Leaving a dedicated W'95 EIDE disk > as the master drive on the primary EIDE controller, > modifying the MBR and installing booteasy > B) Adding a second EIDE disk for FreeBSD - > ** as the slave drive on the primary EIDE controller ** > partitioning the usual way, and modifying the MBR > and installing booteasy > > This last, that is, adding the FreeBSD disk as the *slave > drive on the primary controller*, turned out to be the > only way I could get the booteasy loader to work. I never > could get it to boot off the secondary controller, which > also now happens to have an ATAPI CDROM on it, which I moved > from the primary EIDE to the secondary EIDE. I tried several > permutations and combinations of kernels compiled with > "config kernel root on wd[0-2], moving drives around, etc., > and finally got it to work as above. YMMV, but, for some reason, > I found that the root partition had to live on a drive > on the primary controller, in which case it worked perfectly. This is because of the way the bootblocks count WD devices versus how the kernel probes them. The bootblocks assume that 4 disks are installed at wd0..wd3. Even the CDROM is counted. When FreeBSD boots, however, it enumerates the disks separately from CDROMs. So if you have this situation... PRIMARY SECONDARY Master: Disk Single: HD Slave: CDROM Then you have to type wd(2,a)/kernel to boot, but the system will enumerate the disks as... PRIMARY: wdc0 SECONDARY: wdc1 Master: Disk (wd0) Single: HD (wd1) Slave: CDROM (wcd0) Notice that the boot volume you specified, wd2, doesn't mesh with the kernel's idea of the boot disk, wd1. Thus the can't mount root panic. This isn't an easy solve. We need to be able to wire down device IDs to IDE controller positions like we can for the SCSI bus. Until then, you have to move the disk so that it's in the proper order, no intervening cdrom, install, rebuild kernel, then move the disk to the desired position. > Of course, everything works just perfectly on a more recent > system with only a single SCSI disk on it partitioned for FreeBSD. Well, SCSI just generally works better. :-) Doug White | University of Oregon Internet: dwhite@resnet.uoregon.edu | Residence Networking Assistant http://gladstone.uoregon.edu/~dwhite | Computer Science Major
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