If the kernel of the SUSEŽ Linux Enterprise Server for IBM System z is upgraded or modified, it is possible to reboot the system accidentally in an inconsistent state, so standard procedures of IPLing the installed system fail. This most commonly occurs if a new or updated SUSE Linux Enterprise Server kernel has been installed and the zipl program has not been run to update the IPL record. In this case, use the standard installation package as a rescue system from which the zipl program can be executed to update the IPL record.
![]() | Making the Installation Data Available |
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For this method to work, the SUSE Linux Enterprise Server for IBM System z installation data must be available. For details, refer to Section “Making the Installation Data Available” (Chapter 2, Preparing for Installation, ↑Architecture-Specific Information) from Architecture-Specific Information. Additionally, you need the channel number of the device and the partition number within the device that contains the root file system of the SUSE Linux Enterprise Server installation. |
First, IPL the SUSE Linux Enterprise Server for IBM System z installation system as described in the Architecture-Specific Information manual. A list of choices for the network adapter to use is then presented.
Select 4
then 3 to start the rescue system. Depending on the installation environment, you now must specify the parameters for the network adapter and the installation source. The rescue system is loaded and the following login prompt is shown at the end:Skipped services in runlevel 3: nfs nfsboot Rescue login:
You can now login as root
without a password.
In this state, no disks are configured. You need to configure them before you can proceed.
Procedure 52.3. Configuring DASDs
Configure DASDs with the following command:
dasd_configure 0.0.0150 1 0
0.0.0150 is the channel to which the DASD is connected. The
1
means
activate the disk (a 0
at this place would deactivate
the disk). The 0
stands for “no DIAG mode” for the disk (a 1
here would enable DAIG access to the disk).
Now the DASD is online (check with cat /proc/partitions) and can used for subsequent commands.
Procedure 52.4. Configuring a zFCP Disk
To configure a zFCP disk, it is necessary to first configure the zFCP adapter. Do this with the following command:
zfcp_host_configure 0.0.4000 1
0.0.4000
is the channel to which the adapter is
attached and 1
stands
for activate (a 0
here would deactivate the adapter).
After the adapter is activated, a disk can be configured. Do this with the following command:
zfcp_disk_configure 0.0.4000 1234567887654321 8765432100000000 1
0.0.4000
is the previously-used channel ID,
1234567887654321
is the
WWPN (World wide Port Number), and 8765432100000000
is
the LUN (logical
unit number). The 1
stands for activating the disk (a
0
here would
deactivate the disk).
Now the zFCP disk is online (check with cat /proc/partitions) and can used for subsequent commands.
If all needed disks are online, you should now be able to mount the root
device. Assuming that the root device is on the second partition of the DASD
device (/dev/dasda2
), the corresponding command is
mount /dev/dasda2 /mnt.
![]() | File System Consistency |
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If the installed system has not been shut down properly, it may be
advisable to check the file system consistency prior to mounting. This
prevents any accidental loss of data. Using this example, issue the command
fsck |
By just issuing the command mount, it is possible to check whether the file system could be mounted correctly.
For the zipl
command to read the configuration file from
the root device of the installed system and not from the rescue system,
change the root device to the installed system with the
chroot command:
Now execute zipl to rewrite the IPL record with the correct values:
Example 52.3. Installing the IPL Record with zipl
sh-2.05b# zipl building bootmap : /boot/zipl/bootmap adding Kernel Image : /boot/kernel/image located at 0x00010000 adding Ramdisk : /boot/initrd located at 0x00800000 adding Parmline : /boot/zipl/parmfile located at 0x00001000 Bootloader for ECKD type devices with z/OS compatible layout installed. Syncing disks.... ...done
To exit the rescue system, first leave the shell opened by the chroot command with exit. To prevent any loss of data, flush all unwritten buffers to disk with the sync command. Now change to the root directory of the rescue system and unmount the root device of SUSE Linux Enterprise Server for IBM System z installation.
Example 52.4. Unmounting the File System
SuSE Instsys suse:/mnt # cd / SuSE Instsys suse:/ # umount /mnt
Finally, halt the rescue system with the halt command. The SUSE Linux Enterprise Server system can now be IPLed as described in Section 3.9.10, “IBM System z: IPLing the Installed System”.