15 is-is configuration guide, 1 defining an is-is area, 2 configuring is-is interfaces – Riverstone Networks WICT1-12 User Manual
Page 235: Is-is configuration guide -1, Defining an is-is area -1, Configuring is-is interfaces -1, Chapter 15, "is-is configuration guide
Riverstone Networks RS Switch Router User Guide Release 8.0 15-1
15 IS-IS CONFIGURATION GUIDE
This chapter provides an overview of the Intermediate System-Intermediate System (IS-IS) routing protocol
features available for the Riverstone RS Switch Router.
IS-IS is a link state hierarchical routing protocol. In IS-IS, a router is an Intermediate System (IS), and a routing
sub domain is an area. An IS-IS area can contain a number of routers and end devices. Routing within an area is
handled by Level 1 routers, and routing between different areas is handled by Level 2 routers. An IS can route
Level 1 and/or Level 2 traffic.
The IS-IS routing protocol is based on “shortest path first” calculations, similar to the OSPF routing protocol.
Intermediate Systems exchange link state information by transmitting Link State Protocol Data Units (LSPs).
(LSPs are exchanged between same level routers only.) Each IS maintains its own LSP database.
To configure the RS to run IS-IS, you should perform the following tasks:
•
Define the area to which the router will belong.
•
Configure IS-IS interfaces.
•
Start IS-IS.
Optionally, you can modify the default IS-IS parameters that are set globally and on a per-interface basis.
15.1 DEFINING AN IS-IS AREA
An IS-IS area is a network sub domain that consists of routers and the end devices connected to them. All routers
in an area maintain detailed routing information about destinations within the area. When you define the area of
the RS, all its interfaces belong to that area. Interfaces on an RS cannot belong to separate areas.
To define the IS-IS area to which the RS will belong, enter the following command in Configure mode:
15.2 CONFIGURING IS-IS INTERFACES
IS-IS is disabled on all RS interfaces by default. To enable IS-IS on an interface, first configure an IP interface
using the
interface create
command. Then, enable IS-IS on the interface. You can enable IS-IS on all IP
interfaces by specifying the
all
keyword.
Defines an IS-IS area.
isis add area
<string>