HP Insight Cluster Management Utility HP Insight CMU diskless environments, Modifying an image

4.7.2 Modifying an image

Modifications can consist of simple manual commands such as adding, removing, or modifying files. However, complex operations using chroot commands on the expanded image directory are also possible, such as installing a new rpm.

IMPORTANT: When using chroot, HP recommends performing chroot mount /proc or chroot mount /sys in the image directory before executing other chroot commands.

For example:

#chroot /opt/cmu/image/rh5u4_x86_64/image_mountpoint/ mount /sys

#chroot /opt/cmu/image/rh5u4_x86_64/image_mountpoint/ mount /proc

#cp /data/repositories/rh5u4_x86_64/Server/dhcp-3.0.5-21.el5.x86_64.rpm /opt/cmu/image/rh5u4_x86_64/image_mountpoint/tmp

#chroot /opt/cmu/image/rh5u4_x86_64/image_mountpoint rpm -ivh /tmp/dhcp-3.0.5-21.el5.x86_64.rpm

warning: /tmp/dhcp-3.0.5-21.el5.x86_64.rpm: Header V3 DSA signature:

NOKEY, key ID 37017186

Preparing...

########################################### [100%] 1:dhcp

########################################### [100%]

#chroot /opt/cmu/image/rh5u4_x86_64/image_mountpoint/ umount /sys

#chroot /opt/cmu/image/rh5u4_x86_64/image_mountpoint/ umount /proc

IMPORTANT: When using chroot, some commands can alter the management node system:

•mount -a—Mounts the partitions of the management node in the image. Any further modifications to the subdirectories modifies the management node tree and not the cloning image.

•grub-install—Replaces the boot loader of the management node.

4.7.3Saving a modified cloning image

After modifications are complete, run the cmu_image_commit command to save the content of an expanded image into an HP Insight CMU cloning image. Depending on the cloning image size, this script can take several minutes to complete. The modified image can either replace the image itself or be saved as new cloning image.

To update cloning image rh5u4_x86_64 with the modifications:

#/opt/cmu/bin/cmu_image_commit -i rh5u4_x86_64

The original archive files are renamed in the image directory and the new image content is compacted into one archive file per partition. The new image content replaces each original archive file.

To save the modifications to cloning image rh5u4_x86_64 to a new cloning image rh5u4_mod:

#/opt/cmu/bin/cmu_image_commit -i rh5u4_x86_64 -n rh5u4_mod

NOTE: The -noption registers a new logical group to the HP Insight CMU database. No nodes are added into this new group.

4.8 HP Insight CMU diskless environments

4.8.1 Overview

HP Insight CMU implements a diskless feature derived from Red Hat to build diskless clusters.

4.8 HP Insight CMU diskless environments 55