The transfer uses TCP/IP sockets. The clone image is saved to the local disk. The node then asks the image server if any successors are waiting for upload. If any successors are waiting, the node then starts to transfer the image to a group member, while the image server uploads a third one. This process is called the tree propagation algorithm.

After a node has received a completed image, it attempts to upload to another node within the entity. This mechanism speeds up the propagation process and takes advantage of the available network bandwidth. Each time a node receives a clone image, the node uncompresses the image on the local disk. This is designed to speed up the cloning process. The process is also performed on all secondary servers.

When the HP Insight CMU list of nodes to be cloned completes, each node within the group has an identical system disk image on the local system disk. To reboot on the local disk, some node specific files must be adjusted on a node-by-node basis, such as the TCP/IP node address and hostname. HP Insight CMU adjustment is limited to the TCP/IP name and address of the primary network interface. The TCP/IP hostname and IP address set for compute nodes is defined by the DHCP configuration file on the image server, for example /etc/dhcpd.conf.

During cloning, secondary servers boot from the primary server.

Then, each compute node boots from its secondary server.

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HP Insight Cluster Management Utility manual Cloning mechanisms