Chassis and Power Supplies
Power Supply Redundancy
OmniSwitch 7700/7800 Hardware Users Guide
April 2005
page 2-23
Power Supply Redundancy
While the switch is running, all power supplies installed and operating share the electrical load. If a power
supply is physically removed from the chassis or fails unexpectedly, the remaining power supplies auto-
matically take up the load without disrupting the switch. However, for this failover to work, you must
have at least one redundant power supply installed and running in your switch at all times. Refer to the
important information on pages
to determine minimum switch power requirements, as
well as redundant power supply requirements.
Redundancy Defined
Power supply redundancy is defined as having at least one power supply more than the minimum switch
requirement.
In example below, a minimum of two power supplies is required to support the switch’s basic operations
(see
). A third power supply provides failover (i.e.,
redundancy
) if one power supply is physi-
cally pulled from the chassis or quits unexpectedly.
OS7800 Power Supply Redundancy Example
Non-Redundant Power Configuration.
The OS7800 switch illustrated at left con-
tains both primary and redundant CMMs,
as well as nine NIs (eight OS7-ENI-C24
modules and one OS7-GNI-U2). Note that
the chassis contains two power supplies.
According to the general guidelines listed
on
, an OS7800 switch with nine
NIs requires a minimum of two power sup-
plies for basic switch operations. The
example shown at left does not have power
redundancy. If a power supply is physically
removed from the chassis or fails unexpect-
edly, switch operations may be disrupted.
Three Power
Supplies Installed
Two Power
Supplies Installed
Redundant Power Configuration.
A third power supply has been added to the
same switch. This exceeds the switch’s
minimum requirement of two power sup-
plies as outlined on
The switch has power redundancy. If one
power supply is removed from the chassis
or fails unexpectedly, the redundant supply
will help carry the load requirements.
Switch operations will not be disrupted.
Note.
The table on page
provides
general power supply guidelines only
. To
verify that your switch has redundant
power, you must follow the steps outlined
beginning on
Nine NI Modules and
Redundant CMMs Installed
