Cisco 5510 - ASA SSL / IPsec VPN Edition Configuration Guide

59-3
Cisco ASA 5500 Series Configuration Guide using ASDM
OL-20339-01
Chapter 59 Configuring Active/Standby Failover
Information About Active/Standby Failover
Note On the standby unit, the configuration exists only in running memory. To save the configuration to the
flash memory on the standby unit, select File > Save Running Configuration to Flash from the menu
bar. Startup configurations saved on external servers are accessible from either unit over the network and
do not need to be saved separately for each unit. Alternatively, you can copy the contexts on disk from
the active unit to an external server, and then copy them to disk on the standby unit, where they become
available when the unit reloads.
Command Replication
Command replication always flows from the active unit to the standby unit. As you apply your changes
to the active unit in ASDM, the associated commands are sent across the failover link to the standby unit.
You do not have to save the active configuration to flash memory to replicate the commands.
Table 59-1 lists the commands that are and are not replicated to the standby unit:
Note Changes made on the standby unit are not replicated to the active unit. If you enter a command on the
standby unit, the adaptive security appliance displays the message
**** WARNING **** Configuration
Replication is NOT performed from Standby unit to Active unit. Configurations are no
longer synchronized.
This message displays even when you enter many commands that do not affect
the configuration.
Replicated commands are stored in the running configuration. To save replicated commands to the flash
memory on the standby unit, select File > Save Running Configuration to Flash from the menu bar.
Failover Triggers
The unit can fail if one of the following events occurs:
• The unit has a hardware failure or a power failure.
Table 59-1 Command Replication
Command Replicated to the Standby Unit Commands Not Replicated to the Standby Unit
all configuration commands except for the mode,
firewall, and failover lan unit commands
all forms of the copy command except for copy
running-config startup-config
copy running-config startup-config all forms of the write command except for write
memory
delete crypto ca server and associated sub-commands
mkdir debug
rename failover lan unit
rmdir firewall
write memory mode
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Cisco 5510 - ASA SSL / IPsec VPN Edition Specifications

General

Brand	Cisco
Model	5510 - ASA SSL / IPsec VPN Edition
Category	Firewall
Language	English