HP ProCurve 3500-24 Reference Manual page 16

Rather than duplicate status information and control buttons on each of the dual management modules, the
System Support Module creates a common location for:
• System "Reset" and "Clear" buttons
• Status LEDs for internal power supplies, external power supply (EPS), fabric and interface modules
• LED Mode indicators (which dictate the function of the Mode LED on individual ports) to indicate activity (Act),
full-duplex operation (FDx), speed (Spd), delivery of PoE power (PoE), and a configurable User Mode (Usr)
1
All components contained on the SSM are very low failure rate functions (as evidenced from the very low failure
rate of HP ProCurve 5400zl series chassis and predecessor chassis products) . But in the event of a failure
of any of these components, this module can be replaced without removing any network cables or interface
modules—as required by other competitor designs when there is a need to service some components mounted
to the backplane .
Since the SSM is a required module for the operation of the Switch 8212zl chassis, it is not a hot-swappable
module . Although no damage will occur to the chassis if the SSM is removed during operation, its removal will
indeed power down the system (similar to pulling a sole management module with no standby MM in place) .
To prevent the accidental removal of the module, the SSM is mounted to the chassis with tamper-resistant
screws (TRSs) . TRSs also contribute to the low failure rate probability for the SSM . Contributors to module failure
included static discharge through user handling or misalignment of pins upon reinsertion .
Figure 5. Tamper-Resistant Torx-20 screws and wrench (included with spare SSM)
Slotted/Torx-10 screws
Tamper-Resistant Torx-20
(used on other modules)
(only on the SSM)
For TORX screws with
Center Security Pin
As with many critical components, a best practice would be to have a spare SSM onsite, and HP ProCurve
includes a TRS wrench with every separately purchased J9095A module should you ever need to replace a
failed SSM . All other modules can be removed by using a blade screwdriver or T10 Torx driver .
Figure 6. Close-up of System Support Module (SSM) in a typical state
User Mode (Usr) will be enabled in a future software release.
1
16