Cisco Systems OL-7396-01 Configuring a Summary Address

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ATM Switch Router Software Configuration Guide
OL-7396-01
Chapter11 Configuring ATM Routing and PNNI
Basic PNNI Configuration
Configuring a Summary Address
You can configure summary addresses to reduce the amount of information advertised by a PNNI node
and contribute to scalability in large networks. Each summary address consists of a single reachable
address prefix that represents a collection of end system or node addresses. We recommend that you use
summary addresses when all end system addresses that match the summary address are directly
reachable from the node. However, this is not always required because route s are always selected by
nodes advertising the longest matching prefix to a destination address.
By default, each lowest-level node has a summary address equal to the 13-byte address prefix of the ATM
address of the switch. This address prefix is advertised into its peer group.
You can configure multiple addresses for a single switch which are used during ATM address migration.
ILMI registers end systems with multiple prefixes during this period until an old address is removed.
PNNI automatically creates 13-byte summary address prefixes from all of its ATM addresses.
You must configure summary addresses (other than the defaults) on each node. Each node can have
multiple summary address prefixes. Use the summary-address command to manually configure
summary address prefixes.
Note The no auto-summary command removes the default summary address(es). Use the noauto-summary
command when systems that match the first 13-bytes of the ATM address(es) of your switch are attached
to different switches. You can also use this command for security purposes.
To configure a summary address, perform these steps, beginning in global configuration mode:
Example
The following example shows how to remove the default summary address(es) and ad d summary
address 47.009181005670:
Switch(config)# atm router pnni
Switch(config-atm-router)# node 1
Switch(config-pnni-node)# no auto-summary
Switch(config-pnni-node)# summary-address 47.009181005670
Command Purpose
Step1 Switch(config)# atm router pnni
Switch(config-atm-router)#
Enters ATM router PNNI mode.
Step2 Switch(config-atm-router)# node node-index
Switch(config-pnni-node)#
Enters node configuration mode.
Step3 Switch(config-pnni-node)# no auto-summary Removes the default summary address(es).
Step4 Switch(config-pnni-node)# summary-address
address-prefix
Configures the ATM PNNI summary address
prefix.