Cisco ASA 5512-X Cli Configuration Guide

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Cisco ASA Series CLI Configuration Guide
Chapter 1 Configuring a Cluster of ASAs
Information About ASA Clustering
After the slave members learn the routes from the master unit, each unit makes forwarding decisions
independently.
The OSPF LSA database is not synchronized from the master unit to slave units. If there is a master unit
switchover, the neighboring router will detect a restart; the switchover is not transparent. The OSPF
process picks an IP address as its router ID. Although not required, you can assign a static router ID to
ensure a consistent router ID is used across the cluster.
Dynamic Routing in Individual Interface Mode
In Individual interface mode, each unit runs the routing protocol as a standalone router, and routes are
learned by each unit independently.
Figure 1-2 Dynamic Routing in Individual Interface Mode
In the above diagram, Router A learns that there are 4 equal-cost paths to Router B, each through an
ASA. ECMP is used to load balance traffic between the 4 paths. Each ASA picks a different router ID
when talking to external routers.
You must configure a cluster pool for the router ID so that each unit has a separate router ID.
Multicast Routing
• Multicast Routing in Spanned EtherChannel Mode, page 1-20
• Multicast Routing in Individual Interface Mode, page 1-21
Multicast Routing in Spanned EtherChannel Mode
In Spanned EtherChannel mode, the master unit handles all multicast routing packets and data packets
until fast-path forwarding is established. After the connection is established, each slave can forward
multicast data packets.
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Router B
Cluster M
ECMP Load BalancingAll units are using OSPF
with neighboring routers

Cisco ASA 5512-X Specifications

General

Brand	Cisco
Model	ASA 5512-X
Category	Firewall
Language	English