Creating High-availability Power Solutions for the ProLiant ML570 Server

creating high-availability power solutions for the ProLiant ML570 server
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abstract
Providing redundant power is imperative for maintaining high availability of servers.
Therefore, the ProLiant ML570 server was designed to support hot-pluggable N+1
redundant power supplies. The way those power supplies are configured, however, is
equally important for maintaining server availability. This paper explains common power
configurations that can reduce server reliability and describes an optimum solution using
a dual-input power distribution unit (PDU) to provide fault resilience for the ProLiant
ML570 server in mission-critical environments.
power supplies
in the ProLiant
ML570 server
To provide unmatched reliability and the highest levels of availability, the ProLiant
ML570 server is designed to support N+1 redundant power supplies. Depending on the
configuration requested by the customer, the ProLiant ML570 server ships with two or
three hot-pluggable power supplies. While two power supplies are required to power
the server, another power supply can be added to provide redundant power for the
server.
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Then, if one of the standard power supplies fails, the optional power supply will
take over the load of the failed power supply to maintain server availability. For more
information on the ProLiant ML570 server, please visit
www.compaq.com/products/servers/proliantml570/index.html
.
single points of
failure in typical
power
configurations
To increase redundancy, many data centers are now providing AC power feeds from
two separate power grids. In theory, an environment with two power grids would
provide availability for the server in the event of a power outage. However the
redundancy of a server with three power supplies can be compromised in this situation.
Typically, two of the server’s power supplies would be connected to one power grid,
and the third power supply would be connected to the second power grid (as shown in
figure 1).
figure 1: typical power supply configuration in an environment with two power grids
Power
Supply
Power
Supply
Power
Supply
ProLiant ML570 Server
Power Grid A Power Grid B
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Although the ProLiant ML570 server is designed to support 2+1 redundancy, certain configurations can run in redundant mode using
only two power supplies. To enable 1+1 redundancy, the default power supply configuration must be changed during ROM-based setup.
For more information about 1+1 redundancy for this server, please refer to the QuickSpecs for the ProLiant ML570 server.