Cisco ASA 5505 - Manual (Page 1386)

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Cisco ASA 5500 Series Configuration Guide using the CLI
Chapter 64 Configuring IPsec and ISAKMP
Clearing Security Associations
Providing Site-to-Site Redundancy
You can define multiple IKEv1 peers by using crypto maps to provide redundancy. This configuration is
useful for site-to-site VPNs. This feature is not supported with IKEv2.
If one peer fails, the ASA establishes a tunnel to the next peer associated with the crypto map. It sends
data to the peer that it has successfully negotiated with, and that peer becomes the active peer. The active
peer is the peer that the ASA keeps trying first for follow-on negotiations until a negotiation fails. At
that point the ASA goes on to the next peer. The ASA cycles back to the first peer when all peers
associated with the crypto map have failed.
Viewing an IPsec Configuration
Table 64-6 lists commands that you can enter to view information about your IPsec configuration.
Clearing Security Associations
Certain configuration changes take effect only during the negotiation of subsequent SAs. If you want the
new settings to take effect immediately, clear the existing SAs to reestablish them with the changed
configuration. If the ASA is actively processing IPsec traffic, clear only the portion of the SA database
that the configuration changes affect. Reserve clearing the full SA database for large-scale changes, or
when the ASA is processing a small amount of IPsec traffic.
Table 64-7 lists commands you can enter to clear and reinitialize IPsec SAs.
Table 64-6 Commands to View IPsec Configuration Information
Command Purpose
show running-configuration crypto Displays the entire crypto configuration,
including IPsec, crypto maps, dynamic crypto
maps, and ISAKMP.
show running-config crypto ipsec Displays the complete IPsec configuration.
show running-config crypto isakmp Displays the complete ISAKMP configuration.
show running-config crypto map Displays the complete crypto map configuration.
show running-config crypto dynamic-map Displays the dynamic crypto map configuration.
show all crypto map Displays all of the configuration parameters,
including those with default values.
Table 64-7 Commands to Clear and Reinitialize IPsec SAs
Command Purpose
clear configure crypto Removes an entire crypto configuration, including IPsec,
crypto maps, dynamic crypto maps, and ISAKMP.
clear configure crypto ca trustpoint Removes all trustpoints.
clear configure crypto dynamic-map Removes all dynamic crypto maps. Includes keywords that
let you remove specific dynamic crypto maps.