IRIS 3010, User Manual

Page: 69 / 145

Version 1.0 SERIES 3000
IRIS OWNER’S GUIDE 4-27 Workstation Administration
4.5.1 Recovery Strategies
Accidental changes to the files critical to U
nix
operation can prevent the U
nix
operating system from booting. Table 4-4 lists some of the files that are most
likely to cause serious problems.
Critical Files
File Purpose
/
/vmunix
/vmunix1
Root directory
Kernel
Kernel that runs on the second disk
/defaultboot
/dev
/dev/console
/dev/syscon
/dev/systty
/dev/md0a
/dev/rmd0a
/dev/drum
Kernel used by default in booting
Device directory
Console tty device
System console device
System tty device
Root file system device
Raw root file system device
Paging device for virtual memory
/etc
/etc/init
/etc/inittab
/etc/passwd
Miscellaneous file directory
Program that starts other user processes
Table for init
Table of user login names, passwords, and
shells
/bin
/bin/su
/bin/sh
/bin/csh
Commands directory
Used to set environment before exec ing shell
Bourne shell
C shell
Table 4-4: Files Critical to U
nix
Operation
The following subsections describe three procedures for diagnosing the
problem and recovering a system that does not boot:
• Using the initialization program, init , to identify the cause of the problem.
• Using a bootable backup tape to load a new root file system onto the disk.
This procedure deletes any data that was on the root file system of the disk.
• Booting the U
nix
kernel from a second disk and reloading the key files.
This approach requires a second disk with a copy of the files needed to boot
the system.