Active/Active Failover - Cisco 7604 Configuration Manual

Understanding Failover
Failover Actions
In Active/Standby failover, failover occurs on a unit basis. Even on systems running in multiple context
mode you cannot fail over individual or groups of contexts with Active/Standby failover.
Table 14-1
failover policy (failover or no failover), the action taken by the active unit, the action taken by the
standby unit, and any special notes about the failover condition and actions.
Table 14-1
Failure Event
Active unit failed (power or
hardware)
Formerly active unit recovers No failover
Standby unit failed (power or
hardware)
Failover link failed during
operation
Failover link failed at startup
State link failed
Interface failure on active unit
above threshold
Interface failure on standby
unit above threshold

Active/Active Failover

This section describes Active/Active failover. This section includes the following topics:
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Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide using ASDM
14-12
shows the failover action for each failure event. For each failure event, the table shows the
Failover Behavior
Policy Active Action
Failover n/a
Become standby
No failover Mark standby as
failed
No failover Mark failover
interface as failed
No failover Mark failover
interface as failed
No failover No action
Failover Mark active as
failed
No failover No action
Active/Active Failover Overview, page 14-13
Primary/Secondary Status and Active/Standby Status, page 14-13
Device Initialization and Configuration Synchronization, page 14-14
Command Replication, page 14-14
Standby Action Notes
Become active No hello messages are received on
any monitored interface or the
Mark active as
failover link.
failed
No action None.
n/a When the standby unit is marked as
failed, then the active unit will not
attempt to fail over, even if the
interface failure threshold is
surpassed.
Mark failover You should restore the failover link
interface as failed as soon as possible because the
unit cannot fail over to the standby
unit while the failover link is down.
Become active If the failover link is down at
startup, both units will become
active.
No action State information will become out
of date, and sessions will be
terminated if a failover occurs.
Become active None.
Mark standby as When the standby unit is marked as
failed failed, then the active unit will not
attempt to fail over even if the
interface failure threshold is
surpassed.
Chapter 14 Configuring Failover
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