unix not found

If the system displays the unix not found message after the system starts to boot, the unix file is missing. The unix file contains the bootable image of the UNIX system kernel. If unix is missing, you can boot from another kernel file, (such as unix.old or unix.safe) by entering the alternate kernel name at the Boot: prompt.

If there are no other kernel files on the system, boot the system from the emergency boot floppy disk set so that you can restore the unix file:

1. Insert the boot floppy disk in the drive and reboot the machine.

2. At the Boot: prompt, enter:
   
   fd(60)unix.Z root=hd(42) swap=hd(41)

   This loads the kernel from the boot floppy disk and mounts the root filesystem on the hard disk.

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   NOTE: If you have changed the location of the swap device, you should substitute it for hd(41).

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3. Bring up the system in single-user mode by entering the root password at the prompt.

4. Unmount the /stand filesystem (where boot and the kernel are located):
   
   umount /stand

   The reason for this is that /stand is normally mounted read-only and you must unmount it and mount it again before you can replace the kernel.
   

5. Re-mount /stand:
   
   mount /stand

6. Mount the boot floppy disk:
   
   mount -r /dev/fd0 /mnt

7. While the floppy disk is in the drive, restore unix:
   
   cp /mnt/unix.Z /stand

   This copies the compressed unix kernel file from the boot floppy disk to the hard disk. You do not need to uncompress the kernel.

8. Before you remove the floppy disk from the drive, unmount the floppy disk (/dev/fd0):
   
   umount /mnt

9. Remove the floppy disk from the drive and bring down the system with the haltsys(ADM) command.

10. Reboot the system by pressing <Enter> at the Boot: prompt.

11. The kernel you loaded from the boot disk does not include any changes you've made since creating your emergency boot floppy disk set. You should immediately relink your kernel as described in ``Relinking the kernel''. Whenever you make changes to your system configuration that add drivers and relink your kernel, you should create a new emergency boot floppy disk set.