• Link events
• Interrupts
• Layer 2 and Layer 3 forwarding table updates
• Dynamic user authentication updates such as 802.1X or multi-device port authentication
• Routing protocols OSPFv2 and OSPFv3 updates if NSR is enabled.
Dynamic events are synchronized in such a way that if the active CPU fails before fully executing an
event, the standby CPU (newly active CPU) will execute the event after the failover. Also, if the active
CPU aborts the event, the standby CPU will abort the event as well.
NOTE
Since both the standby and active management modules run the same code, a command that brings
down the active management module will most likely bring down the standby management module.
Because all configuration commands are synchronized from active to standby management module in
real time, both management modules will reload at almost the same time. This in turn will cause the
system to reset all interface modules (similar to the behavior when the
reboot
command is executed)
and will cause packet loss associated with a system reboot.
NOTE
If the new active management module becomes out-of-sync with an interface module, information on
the interface module can be overwritten in some cases, which can cause an interruption of traffic
forwarding.
How a Hitless switchover or failover impacts system functions
Fora description of the feature’s impact to major system functions, refer to
Supported protocols and
services for hitless management events
on page 123.
Enabling hitless failover on the FSX 800 and FSX 1600
Hitless failover is disabled by default. When disabled, the following limitations are in effect:
• If a failover occurs, the system will reload. The following message will display on the console prior
to a reload.
STBY:- - - - Active Hitless Failover is disabled. Re-setting the system - -
• Manual switchover (CLI command
switch-over-active-role
) is not allowed. If this command is
entered, the following message will display on the console:
Switch-over is not allowed. Reason: hitless-failover not configured.
NOTE
Hitless OS upgrade is
not
impacted by this option and is supported whether or not hitless failover is
enabled.
NOTE
Synchronization between the active management module and standby management module will occur
whether or not hitless failover is enabled.
How a Hitless switchover or failover impacts system functions
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FastIron Ethernet Switch Administration Guide
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