Date: Sat, 27 Nov 2004 20:14:02 +0100 From: Erik Norgaard <norgaard@locolomo.org> To: "freebsd-questions@freebsd.org" <freebsd-questions@freebsd.org> Subject: Lost MBR/wrong disk geometry Message-ID: <41A8D1FA.8030005@locolomo.org>
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Hi, It appears that I have screwed my disk (60GB) thoroughly. I had used the sample install.cfg for sysinstall but it has "partition=exclusive" and not "all". I did dd if=/dev/zero of=/dev/ad0 count=1k as explained in the faq, and the exclusive partioning was gone. I can run sysinstall, slice up the disk and install stuff. But on reboot the system doesn't find a usefull mbr. I can boot up a rescue disk, mount the partitions, read data stored and use any programs installed. But I can't recover or create a new mbr with dd if=/boot/mbr of=/dev/ad0 or with /boot/boot0, or use fdisk to manually set slices and active slice, run sysinstall and choose a bootmanager or similar. Please, how to I get back an mbr and a working partition table? Thanks! Cheers, Erik PS: When sysinstall ran first, it complained about a wrong geometry, 116280/16/63 and tried to rewrite it to 7296/255/63. The bios reports 28728/16/255 and the label on the disk sais 16383/16/63. Accepting the geometry from sysinstall would make the installation complete but on reboot the system booted up with the old geometry. On my laptop my disk (40GB) has geometry 77520/16/63 so I hacked up sysinstall to accept the geomtry (a simple change). With this I can slice up the disk and install the system. I don't know if this is right, but from my current state, I'd say that the only thing is the mbr not being written correctly to the disk... -- Ph: +34.666334818 web: www.locolomo.org S/MIME Certificate: http://www.locolomo.org/crt/2004071206.crt Subject ID: A9:76:7A:ED:06:95:2B:8D:48:97:CE:F2:3F:42:C8:F2:22:DE:4C:B9 Fingerprint: 4A:E8:63:38:46:F6:9A:5D:B4:DC:29:41:3F:62:D3:0A:73:25:67:C2
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