Single-Topology Ipv6; Configure Single Topology For Is-Is - Cisco NCS 5500 Series Configuration Manuals

Implementing IS-IS
• The level-1-2 keyword configures the software to perform both Level 1 and Level 2 routing. Both Level 1 and
Level 2 adjacencies are established. The router acts as a border router between the Level 2 backbone and its Level 1
area.
Step 5 commit
Step 6
show isis [ instance instance-id ] protocol
Example:
RP/0/RP0/CPU0:router# show isis protocol
(Optional) Displays summary information about the IS-IS instance.

Single-Topology IPv6

Single-topology IPv6 allows IS-IS for IPv6 to be configured on interfaces along with an IPv4 network protocol.
All interfaces must be configured with the identical set of network protocols, and all routers in the IS-IS area
(for Level 1 routing) or the domain (for Level 2 routing) must support the identical set of network layer
protocols on all interfaces.
In single-topology mode, IPv6 topologies work with both narrow and wide metric styles in IPv4 unicast
topology. During single-topology operation, one shortest path first (SPF) computation for each level is used
to compute both IPv4 and IPv6 routes. Using a single SPF is possible because both IPv4 IS-IS and IPv6 IS-IS
routing protocols share a common link topology.

Configure Single Topology for IS-IS

After an IS-IS instance is enabled, it must be configured to compute routes for a specific network topology.
This task explains how to configure the operation of the IS-IS protocol on an interface for an IPv4 or IPv6
topology.
Routing Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.3.x
Single-Topology IPv6
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