HP Cisco MDS 9020 Cisco MDS 9500 Series Hardware Installation Guide (OL-17467- - Page 30

Backplane and Clock Modules Chapter 1 Product Overview Send documentation comments to [email protected]. Backplane and Clock Modules The Cisco MDS 9500 Series includes one or more clock modules that are accessible from the back of the chassis. The Cisco MDS 9513 and 9509 Directors have two field-replaceable clock modules for redundancy and failover. The Cisco MDS 9506 Director has one field-replaceable clock module. In the unlikely event of a clock module failure, the Cisco MDS 9500 Series generates an error message and a switchover from one clock module to the other, causing the system to reset automatically. Cisco recommends that the failed clock module be replaced during a maintenance window. See the "Removing and Installing Clock Modules" section on page 2-76 for information on replacing clock modules. There are two LEDs per clock module. Figure 1-5 shows the upper and lower LEDs. Figure 1-5 Clock Module LEDs 2 CLOCK A CLOCK B 181336 1 1 Lower LEDs 2 Upper LEDs Table 1-1 Clock LEDs for the Cisco MDS 9500 Series Directors LED Upper LED Lower LED Status Green Off Green Red Off Description Clock module is active and in use. Clock module is in standby mode. Power supply is on and working properly. Power supply is not in a stable state. If this indication continues after initial power on, check that all connections are secure. Normal operation or power supply is turned off. Cisco MDS 9500 Series Hardware Installation Guide 1-8 OL-17467-02