Operation Manual – Reliability
H3C S9500 Series Routing Switches
Chapter 2 HA Configuration
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Chapter 2 HA Configuration
2.1 Introduction to HA
HA (high availability) is to achieve a high availability of the system and to recover the
system as soon as possible in the event of SRPU failures so as to shorten the MTBF
(Mean Time Between Failure) of the system.
The functions of HA are mainly implemented by the application running on master and
slave boards. The two boards are working in the master-slave mode: one board works
in master mode, the other work in slave mode. If the master-slave system detects a
fault in the master board, a hot master-slave switchover will be performed automatically.
The slave board will try to connect and control the system bus while the original master
board will try to disconnect from the bus. Thus, the master-slave switchover of the
active system is completed, and at the same time the original master board is reset to
recover as soon as possible and then function as the slave board. Even if the master
board fails, the slave board can also take its role to ensure the normal operation, and
the system can recover as soon as possible.
S9500 series support hot swap of master and slave boards. The hot swap of master
boards will cause master-slave switchover.
S9500 series support manual master-slave switchover. You can change the current
board state manually by executing command.
The configuration file of slave is copied from master board at the same time. This can
ensure that the slave system continues to operate in the same configuration as that of
the original active system after the slave system has taken place of the active system.
S9500 series support automatic synchronization. The active system stores its
configuration file and backup the configuration file to the slave system simultaneously
when the master's configuration file is modified, ensuring the consistency of the
configurations of the active system and slave system.
Besides, the system can monitor the power supply and the working environment of the
system and give timely alarms to avoid the escalation of failures and ensure safe
operations of the system.
Caution:
The S9500 active and standby boards must both be in position and run the same
version of program. Otherwise, the switch cannot operate normally.
