Configuration Tasks for IS-ISThe following describes the configuration tasks for IS-IS.• Enabling IS-IS• Configure Multi-Topology IS-IS (MT IS-IS)• Configuring IS-IS Graceful Restart• Changing LSP Attributes• Configuring the IS-IS Metric Style• Configuring IS-IS Cost• Changing the IS-Type• Controlling Routing Updates• Configuring Authentication Passwords• Setting the Overload Bit• Debuging IS-ISEnabling IS-ISBy default, IS-IS is not enabled.The system supports one instance of IS-IS. To enable IS-IS globally, create an IS-IS routing process and assign a NET address. To exchangeprotocol information with neighbors, enable IS-IS on an interface, instead of on a network as with other routing protocols.In IS-IS, neighbors form adjacencies only when they are same IS type. For example, a Level 1 router never forms an adjacency with a Level 2router. A Level 1-2 router forms Level 1 adjacencies with a neighboring Level 1 router and forms Level 2 adjacencies with a neighboring Level2 router.NOTE: Even though you enable IS-IS globally, enable the IS-IS process on an interface for the IS-IS process to exchangeprotocol information and form adjacencies.To configure IS-IS globally, use the following commands.1 Create an IS-IS routing process.CONFIGURATION moderouter isis [tag]tag: (optional) identifies the name of the IS-IS process.2 Configure an IS-IS network entity title (NET) for a routing process.ROUTER ISIS modenet network-entity-titleSpecify the area address and system ID for an IS-IS routing process. The last byte must be 00.For more information about configuring a NET, refer to IS-IS Addressing.3 Enter the interface configuration mode.CONFIGURATION modeinterface interfaceEnter the keyword interface then the type of interface and slot/port information:• For a 10-Gigabit Ethernet interface, enter the keyword TenGigabitEthernet then the stack/slot/port/subport information.444 Intermediate System to Intermediate System
