Use a rescue image from an NWSSTG

 

A rescue image contains the minimal version of all the basic diagnostic tools, drivers and other utilities that would be useful for checking a previously existing logical partition. To use the rescue image that you created on NWSSTG, use the following steps:

  1. Disconnect the failed partition's virtual storage space (if applicable) through WKRNWSSTG.

  2. Connect your rescue storage space as the first drive to the NWSD and reconnect the original storage space (where applicable) as the second drive.

  3. Edit the NWSD for the failed partition to start from IPL Source *NWSSTG. Also edit the IPL Parameters Field to reflect the root partition on the rescue storage space. For most distributions this is a parameter like 'root=/dev/hda3' or 'root=/dev/vda1' Refer to your Linux documentation for assistance or look at other running partitions using the command 'cat /proc/iSeries/mf/B/cmdline'.

  4. Boot the partition.

  5. If the existing root partition is on native disk, you may need to insert the ibmsis driver using the command "insmod ibmsis".

  6. Create a mount point to which you will mount the root partition of the network storage space you are trying to rescue. You can use a command like "mkdir /mnt/rescue".

  7. Now mount the root partition of the network storage space you are trying to rescue. You mount a drive using the command "mount -t your partition's type partition's location mount point" where the partition's type is the format of the partition like ext2 or reiserfs, the partition's location is something like /dev/hdb3 (for non-devfs), /dev/hd/disc1/part3 (for devfs server) or /dev/sda2 in the case of a partition on native disk. It is important to note that the drive you are trying to rescue, when using virtual disk, will be the second drive rather than the first drive. (i.e. If the drive was /dev/hda3 when the partition was running normally, it will be /dev/hdb3 in the rescue server.) Here again, your Linux documentation or the configuration files you created when you created the rescue NWSSTG will help you determine the device for the root of the partition you are trying to rescue. Finally, your mount point will be something like /mnt/rescue if you use the example from above.
After following the steps listed above, you can either use the rescue tools provided in your rescue storage space against the mount point you created or you can change root to that partition using "chroot mount point" to work on the partition from within its own storage space. See Build a rescue image on an NWSSTG for more information.

 

Parent topic:

Back up and recover a logical partition