User's Manual

Using FlexAddress 215

Using FlexAddress

The FlexAddress feature is an optional upgrade that allows server modules to

replace the factory-assigned World Wide Name and Media Access Control

(WWN/MAC) network IDs with WWN/MAC IDs provided by the chassis.

Every server module is assigned unique WWN and/or MAC IDs as part of the

manufacturing process. Before FlexAddress, if you had to replace one server

module with another, the WWN/MAC IDs would change and Ethernet

network management tools and SAN resources would need to be reconfigured

to be aware of the new server module.

FlexAddress allows the CMC to assign WWN/MAC IDs to a particular slot

and override the factory IDs. If the server module is replaced, the slot-based

WWN/MAC IDs remain the same. This feature eliminates the need to

reconfigure Ethernet network management tools and SAN resources for a

new server module.

Additionally, the override action only occurs when a server module is inserted

in a FlexAddress enabled chassis; no permanent changes are made to the

server module. If a server module is moved to a chassis that does not support

FlexAddress, the factory-assigned WWN/MAC IDs will be used.

Before installing FlexAddress, you can determine the range of MAC addresses

contained on a FlexAddress feature card by inserting the SD card into an

USB Memory Card Reader and viewing the file pwwn_mac.xml. This clear

text XML file on the SD card will contain an XML tag mac_start that is the

first starting hex MAC address that will be used for this unique MAC address

range. The mac_count tag is the total number of MAC addresses that the

SD card allocates. The total MAC range allocated can be determined by:

<mac_start> + 0xCF (208 - 1) = mac_end

where 208 is the mac_count and the formula is

<mac_start> + <mac_count> - 1 = <mac_end>

For example:(starting_mac)00188BFFDCFA + 0xCF =

(ending_mac)00188BFFDDC9.

NOTE: Lock the SD card prior to inserting in the USB "Memory Card Reader" to

prevent accidently modifying any of the contents. You

must unlock

the SD card

before inserting into the CMC.