High availability
The following features contribute to the DC SAN Director high-availability design:
•
Redundant, hot-swappable blades and FRUs
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Enhanced data integrity on all data paths
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Fabric Shortest Path First (FSPF) re-routing around failed links
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Integration with Simple Network Management Protocol (SNMP) managers
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Automatic CP failover
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Non-disruptive "hot" software code loads and activation
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Easy configuration, save, and restore
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Hot-swappable World Wide Name (WWN) cards
The high-availability software architecture of the DC SAN Director provides a common framework for
all applications that reside on the system, allowing global and local states to be maintained through
any component failure. High-availability elements consist of the High Availability Manager, the
heartbeat, the fault/health framework, the replicated database, initialization, and software upgrade.
The High Availability Manager controls access to the standby CP blade, facilitates software upgrades,
prevents extraneous switchover activity, closes and flushes streams, provides flow control and message
buffering, and supports a centralized active and standby state.
Reliability
The DC SAN Director uses the following error detection and correction mechanisms to ensure reliability
of data:
•
Data is protected by the Error Detection and Correction mechanism, which checks for encoder
errors and fault isolation (EDFI), such as cyclic redundancy checking (CRC), parity checking,
checksum, and illegal address checking
•
Power-on self-test (POST)
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Dual CP Blades that enable hot, non-disruptive fast firmware upgrades
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Each CP Blade contains one serial port and two Ethernet ports, for management and for service.
Offline CP Blade diagnostics and remote diagnostics simplify troubleshooting. The standby CP
Blade monitors diagnostics to ensure it is operational, in case a failover is required.
•
Bus monitoring and control of blades and other FRUs
Serviceability
The DC SAN Director provides the following features to enhance and ensure serviceability:
•
Modular design with hot-swappable components
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Flash memory that stores two firmware images per CP Blade
•
USB port on CP blades for all tasks that formerly required an FTP/SCP server, including software
and firmware upgrades
•
Non-volatile random-access memory (NVRAM), containing the serial number, serial number, revision
information, and part number information
•
Background health-check daemon
•
Memory scrubber, self test, and bus ping to determine if a bus is not functioning
•
RASlog messages
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HP StorageWorks DC SAN Backbone Director Switch Overview