dmc@ntcsd1.UUCP (David Clemens) (08/07/89)
Something really strange happened yesterday. But first some background... I am working with a PS/2 Model 80 computer running Xenix 386. The system has a 115M hard disk of which 20M is in a DOS partition. Yesterday, I had to reinstall the Xenix operating system(don't ask why, it was my mistake), as well as the drivers for our peripheral equipment(CD-ROM drives, Exelan card, and Computone card). Anyway, after installing the Computone card first, I rebooted the system to test it before installing the rest of the equipment. However, I forgot to take out the disk that had the computone drivers on it. When the computer tried to reboot, it saw the disk in the drive and tried to boot off of it. This apparently accomplished nothing, but when I took the disk out and again tried to reboot, the computer came up in IBM BASIC. (IBM BASIC boots up from memory when a the computer has no other operating system installed) When I use the PS/2 reference disk, it shows the configuration to be the same as it was before the problem and when I boot off of a DOS disk, I can still access the DOS partition on the hard disk. Without the DOS floppy, however, it still boots into BASIC. Does anyone out there know what is wrong with this system? It has been suggested that something wrote over the boot sectors on the HD, so I backed up the DOS partition and reinstalled DOS there using the Select command as if I was installing it for the first time on a new HD. Alas, no dice there. Can anyone out there help me? Mail me any suggestions, and I'll post the first one that works. Thanx in advance... David Clemens Disclaimer: The above ideas were the result of the head-on collision of two apparently random thought processes in the lower portion of my brain. ----------------------------------------------------------------------------- | I'm not weird, I'm normal... | David Clemens | | The rest of the world is weird. | {backbone}!mcnc!rti!ntcsd1!dmc | -----------------------------------------------------------------------------
jcmorris@mbunix.mitre.org (Joseph C. Morris) (08/09/89)
In article <451@ntcsd1.UUCP> dmc@ntcsd1.UUCP (David Clemens) writes: > > [hard disk won't boot -- system enters cassette BASIC] Have you checked the possibility that the partition table on the fixed disk (cylinder 0,head 0, sector 1) hasn't been changed? If you somehow zapped the table to mark a non-bootable partition as bootable, the BIOS boot code would reject the disk and go to C-BASIC instead. If you are able to reach the files on the disk by booting from a diskette, the other data in the partition table is probably valid. Another possibility is that you've clobbered the boot sector for the DOS partition (absolute cylinder 0, head 1, sector 1; this is the first sector of the DOS partition). If the 55AA signature is missing the disk is nonbootable. This doesn't sound likely, however, since you said you've re-installed DOS on the disk. (The c/h/s=0/1/1 is valid only if the DOS partition is the first on the disk.) Use Norton Utilities to inspect absolute c/h/s=0/0/1 (the partition table) and absolute 0/1/1 (the boot record for the first partition) to see if they're contaminated; NU allows you to edit the partition table and set the boot flag as appropriate. Good luck.