Specifications

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OL-4923-01 B0
Note An RSP2 can interoperate with another RSP2, or with an RSP4/4+. It cannot interoperate with an
RSP1, an RSP8, or an RSP16. In the following text, you can substitute references to two RSP2s with
an RSP2 and an RSP4/4+.
When two new RSP2s (or an RSP2 and an RSP4/4+) are installed at the same time, the RSP that occupies
the first even RSP slot on the router is the active (normally the RSP4/4+ if the RSP2 is used in
conjunction with the RSP4/4+), and the RSP that occupies the odd RSP slot is the standby. If a crash has
occurred, the RSP in the odd slot becomes the active and the RSP in the even slot becomes the standby.
HSA is supported with RSP2 on the following routers: Cisco 7507, and Cisco 7513. HSA is not
supported on the Cisco 7505 or the Cisco 7576 routers.
The cold standby procedure, from initial failure to first packet transmission, currently takes
approximately eight to ten minutes.
For more complete HSA configuration information, refer to the Configuration Fundamentals
Configuration Guide and the Configuration Fundamentals Command Reference publications, which are
available online, on the Cisco Documentation CD-ROM, or as printed copies.
HSA Active and Standby Operation
During HSA operation, the active RSP2 card functions as if it were a single processor, controlling all
functions of the router. The standby RSP2 card does nothing but actively monitor the active RSP2 for
failure.
When the standby RSP2 detects a nonfunctional active RSP2, the standby resets itself and takes part in
active-standby arbitration. Active-standby arbitration is a ROM monitor process that determines which
RSP2 card is the active and which is the standby upon startup (or reboot).
If a system crash causes the active RSP2 to fail, the standby RSP2 becomes the new active RSP2 and
uses its own system image and configuration file to reboot the router. The failed RSP2 card (now the
standby) remains inactive until you perform diagnostics, correct the problem, and then issue the standby
reload command.
With HSA operation, use the following guidelines:
• The standby RSP2 should have the same boot image, the same ROM monitor, and the same DRAM
configuration as the active RSP2. (See the “Hardware Prerequisites” section on page 13.)
• The two RSP2 cards are not required to run the same active software image and configuration file.
The standby-mode software is a subset of the active-mode software.
• When enabled, automatic synchronization mode automatically ensures that the active and the
standby RSP2 cards have the same configuration file. (See the “Software Prerequisites” section on
page 13.)
• The console always connects to the active RSP2, so your view is always from the active’s
perspective.
• You must not remove the system active RSP2 while the system is operating; however, the system
standby RSP2 can be removed while the system is operating.
Caution Removing the active RSP2 while the system is operating might cause the system to crash; however,
the system reloads with the standby RSP2 as the new active. To prevent any system problems, do not
remove the active RSP2 while the system is operating.