NO OS

cmlhf

机器在做数据备份时，突然出现
wd0:Error on fixed disk dev1/42 block=2565775 cmd=0*000000c8
status=0*00000040 LBA sector=7020529,cylinder/head=27423/0,启动后系统显示NO OS，用应急启动盘也不行。

fl.w

:em11:
SCO OpenServer Handbook
Chapter 10, Starting and stopping the system


System fails to boot or displays ``NO OS'' message
**************************************************

If the system fails to boot or you see the NO OS message, the blocks containing the partition boot
blocks (/etc/hd0boot and /etc/hd1boot) or masterboot block (/etc/masterboot) may have been
corrupted. To restore them:

1. Insert the boot floppy from your emergency boot floppy set and boot from it. When the
   Boot: prompt appears, enter:

   hd(40)unix

2. Enter single user mode and enter these commands at the root prompt:

   instbb hd /dev/hd0a
   dparam -w

   instbb(ADM) writes the partition boot blocks to the hard disk. dparam(ADM) writes the
   masterboot code to the masterboot block on the hard disk.

For some disks it may also be necessary to stamp the disk geometry as described in dparam
(ADM).