HP Cisco Nexus 5000 Cisco MDS 9000 Family CLI Configuration Guide - Release 4. - Page 285

Chapter 11 Managing System Hardware About Crossbar Management Send documentation comments to [email protected] You can mix and match Generation 1 and Generation 2 hardware on the Cisco MDS 9500 Series Directors running Cisco MDS SAN-OS 3.0(1) or later without compromising the integrity and availability of your SANs based on Cisco MDS 9500 Series Directors. To realize these benefits, you must consider the following operational requirements when removing crossbars for maintenance activities: • Gracefully Shutting Down a Crossbar, page 11-15 • Backward Compatibility for Generation 1 Modules in Cisco MDS 9513 Directors, page 11-15 Gracefully Shutting Down a Crossbar You must perform a graceful shutdown of a crossbar (integrated or external) before removing it from the MDS 9500 Series Director. • You must enter the EXEC mode out-of-service xbar command for a graceful shutdown of external crossbar modules in a Cisco MDS 9513 Director. out-of-service xbar slot Where slot indicates the external crossbar module slot number. Note To reactivate the external crossbar module, you must remove and reinsert or replace the crossbar module. • You must enter the EXEC mode out-of-service module command for a graceful shutdown of integrated crossbars on the supervisor module in a Cisco MDS 9506 or 9509 Director. out-of-service module slot Where slot indicates the chassis slot number on either the Supervisor-1 module or the Supervisor-2 module in which the integrated crossbar resides. Note To reactivate the integrated crossbar, you must remove and reinsert or replace the Supervisor-1 module or Supervisor-2 module. Caution Taking the crossbar out-of-service may cause a supervisor switchover. Backward Compatibility for Generation 1 Modules in Cisco MDS 9513 Directors To provide backward compatibility for a Generation 1 module in a Cisco MDS 9513 chassis, the active and backup Supervisor-2 modules are associated to a specific crossbar module. The Supervisor-2 module in slot 7 is associated with crossbar module 1 and Supervisor-2 module in slot 8 is associated with crossbar module 2. You must plan for the following operational considerations before removing crossbar modules: • Whenever a crossbar module associated with the active Supervisor-2 module goes offline or is brought online in a system that is already online, a stateful supervisor switchover occurs. This switchover does not disrupt traffic. Events that cause a crossbar module to go offline include the following: - Out-of-service requests OL-18084-01, Cisco MDS NX-OS Release 4.x Cisco MDS 9000 Family CLI Configuration Guide 11-15