ServerNet Cluster Manual

ServerNet Cluster Description
ServerNet Cluster Manual—520575-003
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Cluster Switch
Single-wide fiber-optic PICs connect each node to a cluster switch. Double-wide fiber-
optic PICs connect cluster switches on the same fabric in the split-star and tri-star
topologies.
Uninterruptible Power Supply (UPS)
Within a cluster switch, the uninterruptible power supply (UPS), AC transfer switch, and
ServerNet II Switch power supply form the cluster switch power subsystem. The UPS
provides backup power (about two hours) to the ServerNet II Switch during a loss of
AC line current. Figure 1-15 shows the UPS in a switch enclosure.
Figure 1-16 shows a block diagram of the cluster switch.
AC Transfer Switch
The AC transfer switch allows the switch and UPS to draw power from either of two AC
line cords. Power is drawn from the primary rail as long as power is available. If the
primary rail fails, the load is connected to the secondary rail. A power-management
cable connects the UPS and the AC transfer switch to the maintenance port of the
Figure 1-16. Cluster Switch Block Diagram
ServerNet
II
Switc
h
ServerNet
II
Switch AC/
DC
Power
Supply
Secondary
AC Input
Primary
AC Input
Monitor
Port (9 pin)
Power
Monitor
Cables
Proprietary UPS
AC Transfer
Switch
ServerNet Ports
ServerNet II
Switch
AC Power Cord
AC Power Cord
VST930.vsd