Load Sharing; Mixing Ac And Dc Power Supplies; Redundancy; Hot Swapping - HP Aruba 8325 Series Installation And Getting Started Manual

Load sharing

Load sharing occurs when two power supplies are installed in the switch and turned on. Load sharing divides the
total power load of the switch among both power supplies.

Mixing AC and DC power supplies

Installing AC and DC power supplies together in the switch is not supported. The installed power supplies must be
of the same type and same airflow direction.

Redundancy

With power redundancy, the Aruba 8325 switch can continue normal operation even when one power supply fails
or is powered off. When two power supplies are installed, if one becomes unavailable (fails, or is powered off or
removed) the remaining power supply provides full power for the device.

Hot swapping

Hot swapping allows you to replace one failed power supply while the other provides full power. This makes it
unnecessary to shut down the switch during the replacement procedure.
Never insert or remove a power supply while the power cord is connected. Verify that the cord has
been disconnected from the power supply before installation or removal.

Fan assemblies

The Aruba 8325 switch is equipped with six field-replaceable, hot-swappable fan assemblies. Each fan assembly
features individual fans that pull air through the chassis from front to back (FB) or from back to front (BF).
Fans and power supplies installed in a given 8325 switch must have the same cooling air flow direction
(FB or BF). Air flow direction in an 8325 switch is not controlled by software. To change the air flow
direction, replace the power supplies and fans with power and fan units supporting the air flow
direction you want. See Figure 10, Table 20, and Figure 11.
A minimum of five fan assemblies is required for operation. The system will automatically shutdown if
overheating is detected. If five or fewer fan assemblies are installed, the Fan LED will be on amber and
the Global Status LED will flash amber to indicate a fan fault may exist.
System airflow direction (FB or BF) is configured automatically at system initialization and cannot be
reconfigured by the user. System airflow direction is determined by the power supply type installed in
PS1 at initialization time (or PS2 if PS1 is absent). Any Fan assembly or Power supply of conflicting
airflow type will be disabled by the system. Ensure only matching Fan assemblies and power supplies
are used at any given runtime.
Fans designed for the 48-port 8325 switches are not compatible with 32-port 8325 switches and vice-
versa.
Fan models are color-coded for FB or BF cooling air flow.
• Red handle indicates a front-to-back (FB) cooling air flow.
• Blue handle indicates a back-to-front (BF) cooling air flow.
See the following table for fan usage.
Chapter 2 Introducing the Aruba 8325 Switch 25