Compaq HSZ80 manual Restoring Node IDs, 30Creating Storagesets

3–30Creating Storagesets

Node IDs

A node ID is a unique 64-bit number assigned to a subsystem by the Institute of Electrical and Electronics Engineers (IEEE) and set by Compaq manufacturing prior to shipping. The node ID assigned to a subsystem never changes.

Each subsystem’s node ID ends in zero, for example, 5000-1FE1-FF0C-EE00. The controller port IDs are derived from the node ID. In a subsystem with two controllers (a dual-redundant configuration), the port ID of Port 1 for both controllers is the node ID plus 1. In this example, both controllers’ Port 1 port ID would be 5000-1FE1- FF0C-EE01. Similarly, both controllers would have the same port ID for Port 2, 5000- 1FE1-FF0C-EE02. The controllers automatically assign their port IDs.

Use the CLI command SHOW THIS_CONTROLLER to display the subsytem’s node ID. See Chapter 5, “CLI Commands,” for more information about the SHOW command and node IDs. When you enter the SHOW command, the subsystem node ID displays as the REPORTED NODEID and will look like the following:

5000-1FE1-FF0C-EE00

Restoring Node IDs

When you remove a controller to replace it in a dual-redundant configuration, the remaining controller remembers the subsystem node ID. When you install the replacement controller, the remaining controller tells the new controller the node ID; the replacement controller assumes the correct port IDs.

If you have a single-controller configuration, you must have a save configuration disk if you want to be able to automatically restore the node ID in the event of a failure. In this case, the controller could read the node ID from the save configuration disk.

If a situation occurs that requires you to restore the node ID, you can restore it using the node ID and check sum printed on the sticker on the frame into which your controller is inserted. See the SET controller command in Chapter 5, “CLI Commands,” for details about setting the node ID.