Administrator Guide

Related Commands
• net — congure an IS-IS network entity title (NET) for the routing process.
• is-type — assign a type for a given area.
isis circuit-type
Congure the adjacency type on interfaces.
Syntax
isis circuit-type {level-1 | level-1-2 | level-2-only}
To return to the default values, use the no isis circuit-type command.
Parameters
level-1 You can form a Level 1 adjacency if there is at least one common area address between
this system and neighbors. You cannot form Level 2 adjacencies on this interface.
level-1-2 You can form a Level 1 and Level 2 adjacencies when the neighbor is also congured as
Level-1-2 and there is at least one common area, if not, a Level 2 adjacency is established.
This setting is the default.
level-2-only You can form a Level 2 adjacencies when other Level 2 or Level 1-2 routers and their
interfaces are congured for Level 1-2 or Level 2. Level 1 adjacencies cannot be
established on this interface.
Defaults level-1-2
Command Modes INTERFACE
Command History
This guide is platform-specic. For command information about other platforms, see the relevant Dell Networking
OS Command Line Reference Guide.
Version Description
9.8(1.0) Introduced on the Z9100–ON.
9.8(0.0P5) Introduced on the S4048-ON.
9.8(0.0P2) Introduced on the S3048-ON.
9.7(0.0) Introduced on the S6000-ON.
9.5(0.1) Introduced on the Z9500.
9.0.2.0 Introduced on the S6000.
8.3.19.0 Introduced on the S4820T.
8.3.12.0 Introduced on the S4810.
8.3.11.1 Introduced on the Z9000.
Usage Information
Because the default establishes Level 1 and Level 2 adjacencies, you do not need to congure this command.
Routers in an IS-IS system must be congured as a Level 1-only, Level 1-2, or Level 2-only system.
Only congure interfaces as Level 1 or Level 2 on routers that are between areas (for example, a Level 1-2 router)
to prevent the software from sending unused hello packets and wasting bandwidth.
866 Intermediate System to Intermediate System (IS-IS)