Configuring network communication when booting SLES in rescue system mode

This document (7000527) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 10
SUSE Linux Enterprise Server 9

Situation

Many boot issues can be resolved by troubleshooting the server in rescue system mode.
Network communication is not automatically enabled while booting in this mode.
Manual steps are required to enable network communication if data is to be transfered to or from the server.

Resolution

Method 1

Steps to manually enable networking using current rcnetwork scripts on the root file system:

Boot from the SLES operating system media and select the rescue system boot option.
Login as root when prompted.
Confirm the LAN driver has been loaded.
hwinfo --network
There will be an output field called "Driver:" which shows the loaded driver name.
lsmod | less should also show the driver name.
insmod or modprobe the driver manually if it is not loaded.
insmod <driver name.ko>
fdisk -l to see current devices and partitions.
Mount the root partition to /mnt.

Example with /dev/sda2 as the root "/" partition:
mount /dev/sda2 /mnt
NOTE: If it is unknown which device contains root "/", manually mount and umount each device until the one containing root data is found. See step 7 below.
Confirm /mnt contains the correct root "/" partition data.
ll /mnt
NOTE: Root "/" typically has folders like bin, root, opt, lib, dev, etc, proc, srv, sys, var, usr etc......
Rebind proc, sys, and dev.

mount --rbind /proc /mnt/proc
mount --rbind /sys /mnt/sys
mount --rbind /dev /mnt/dev
Remap the root "/" to /mnt.
chroot /mnt
Start the network.
rcnetwork start
Use ifconfig and ping to confirm network communication has been enabled.
Manually mount any other partitions that need to be available.

Method 2

Steps to manually enable networking using ifconfig and route:

Boot from the SLES operating system media and select the rescue system boot option.
Login as root when prompted.
Confirm the LAN driver has been loaded.
hwinfo --network
There will be an output field called "Driver:" which shows the loaded driver name.
lsmod | less should also show the driver name.
insmod or modprobe the driver manually if it is not loaded.
insmod <driver name.ko>
Use the ifconfig command to configure the net device.
ifconfig eth0 <ip address> netmask <netmask value>

Example:
ifconfig eth0 xxx.xxx.xxx.xxx netmask xxx.xxx.xxx.xxx
(Replace the x's in this example with a legitimate IP address and mask.)
Use the route command to configure a communication route.
route add default gw <route value> dev <network interface>

Example:
route add default gw xxx.xxx.xxx.xxx dev eth0
(Replace the x's in this example with a legitimate route.)
Use ping to confirm network communication has been enabled.
Manually mount desired partitions.

Additional Information

The steps listed in this TID assume the boot issue is not related to the availability of the root "/" partition.

Disclaimer

This Support Knowledgebase provides a valuable tool for SUSE customers and parties interested in our products and solutions to acquire information, ideas and learn from one another. Materials are provided for informational, personal or non-commercial use within your organization and are presented "AS IS" WITHOUT WARRANTY OF ANY KIND.