Node Image Template Overview
The Template settings provide a means to modify the function of each node image without having to modify the actual OS delivered to the node. A Template enables you to change the boot parameters from a full installation local to the compute node drive to a partial netboot to a full NFS root.

The Template Name is a name of your choosing.

The Hostname is built from the value of one or more variables. In this dialog box, the default variables are "%{ARCH}" (which returns the architecture) and "%{MAC}" which returns the MAC address of the node's active ethernet port. The combined information is sent via DHCP to the node to establish the hostname. These variables may be modified to your design.

The Architecture is designated for your recollection only and does not affect the actual node image's ability to function on one architecture or another, as this is determined by the kernel and associated binaries that you have built into your image.

The Boot Action may be set to:

boot - reboot from the compute node from its local, internal drive.
nfsboot - will be included with the next version of Y-HPC.
shell - drop into a shell without affecting the local drive.
image - reformat, rebuild the local drive.

The Boot Device is the partition of the drive internal to the compute node from which the compute node will boot.

The Image Device is the drive itself which will be reformatted and then receive the full node image.

The Disk Image is the compute node image selected to be used by this template.

"Format Disk" toggles between reformatting the drive internal to the compute node and subsequent receipt of the full node image; and upgrading the packages already installed on the compute node via an rsync from the selected node image on the head node and those packages already installed on the compute node.

If "Format Disk" is selected, all data on the drive will be lost, the entire selected node image copied from the head node to the compute node upon reboot.

If "Format Disk" is de-selected, the package set contained in the selected node image stored on the head node and that which is already installed on the compute node are compared, the difference copied from head node compute node installed via rsync, performing an installed package upgrade.

Copy an image template

1. Select an existing node template from the Template pull-down menu.
   
   
2. Select "Copy".
   
   
3. In the new pop-up window, enter the name of the new node template and select "Ok".
   
   
4. Once the Template Settings window has refreshed, you may select your new node template.

Rename an image template

1. Select an existing node template from the Template pull-down menu.
   
   
2. Select "Rename".
   
   
3. Enter the new name of the node template and select "Ok".
   
   
4. Once the Template Settings window has refreshed, you may select your new node template.

Delete an image template

1. Select an existing node template from the Template pull-down menu.
   
   
2. Select "Delete".
   
   
3. While this will remove the template data from Y-HPC, for future use, it in no way effects the current function of the compute nodes. They will continue to function as last designated, until re-imaged or given a new template.

Create and Import an image template

1. Select "New".
   
   
2. Enter the name of the Template you desire to create and press "Ok".
   
   
3. Once the Template Settings window has refreshed, select your new template from the pull-down menu. All settings but Boot Action (which defaults to Shell) will be empty, awaiting your input.
   
   
4. Select "Apply" and when complete, "Ok".
   
   
5. Once the Template Settings window has refreshed, you may select your new node template.

Edit an image template
You may edit an existing node image template by simply modifying the displayed parameters and selecting "Apply" when complete.


If required, review Troubleshooting ...