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Parameters
tag (OPTIONAL) This parameter is a unique name for a routing process. A null tag is
assumed if the tag option is not specified. The tag name must be unique for all IP
router processes for a given router.
Defaults Not configured.
Command Modes ROUTER ISIS
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
Configure a network entity title (the net command) to specify the area address and the router system
ID.
To establish adjacencies and establish dynamic routing, enable routing on one or more interfaces.
You can configure only one IS-IS routing process to perform Level 2 routing. A level-1-2 designation
performs Level 1 and Level 2 routing at the same time.
Related
Commands
● net — configures an IS-IS network entity title (NET) for the routing process.
● is-type — assigns a type for a given area.
isis circuit-type
Configure 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
configured 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 configured for Level 1-2 or Level 2. Level 1 adjacencies cannot
be established on this interface.
Defaults level-1-2
Command Modes INTERFACE
Supported Modes Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.2(0.0) Introduced on the MXL 10/40GbE Switch IO Module.
Usage
Information
Because the default establishes Level 1 and Level 2 adjacencies, you do not need to configure this
command. Routers in an IS-IS system must be configured as a Level 1-only, Level 1-2, or Level 2-only
system.
Only configure 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.
696 Intermediate System to Intermediate System (IS-IS)