Configuring the Cost of an IS-IS Interface on IPv6 network

Procedure

1. Configure the IS-IS cost style.
   1. Run system-view

      The system view is displayed.

   2. Run isis [ process-id ]

      The IS-IS view is displayed.

   3. Run cost-style { narrow | wide | wide-compatible | { narrow-compatible | compatible } [ relax-spf-limit ] }

      The IS-IS cost style is configured.

      By default, the cost style of routes received and sent by an IS-IS device is narrow.

   4. Run commit

      The configuration is committed.

   The cost range of an interface and a route received by the interface vary with the cost type.

   • If the cost style is narrow, the cost of an interface ranges from 1 to 63. The maximum cost of a route received by the interface is 1023.

   • If the cost style is narrow-compatible or compatible, the cost of an interface ranges from 1 to 63. The cost of a received route is related to relax-spf-limit.

   • If the cost style is wide-compatible or wide, the cost of the interface ranges from 1 to 16777215. When the cost is 16777215, the neighbor TLV generated on the link cannot be used for route calculation but for the transmission of TE information. The maximum cost of a received route is 0xFFFFFFFF.

2. Configure the cost of an IS-IS interface on IPv6 network.

   Perform any of the following operations to configure the cost of an IS-IS interface on IPv6 network.

   Configure the cost of a specified IS-IS interface on IPv6 network.
   1. Run system-view

      The system view is displayed.

   2. Run interface interface-type interface-number

      The interface view is displayed.

   3. On an Ethernet interface, run undo portswitch

      The interface is switched to Layer 3 mode.

      By default, an Ethernet interface works in Layer 2 mode.

      The mode switching function takes effect when the interface only has attribute configurations (for example, shutdown and description configurations). Alternatively, if configuration information supported by both Layer 2 and Layer 3 interfaces exists (for example, mode lacp and lacp system-id configurations), no configuration that is not supported after the working mode of the interface is switched can exist. If unsupported configurations exist on the interface, delete the configurations first and then run the undo portswitch command.

      If many Ethernet interfaces need to be switched to Layer 3 mode, run the undo portswitch batch interface-type { interface-number1 [ to interface-number2 ] } &<1-10> command in the system view to switch these interfaces to Layer 3 mode in batches.

   4. Run isis ipv6 cost cost [ level-1 | level-2 ]

      The cost of the IS-IS interface on IPv6 network is configured.

      By default, the cost of an IS-IS interface on IPv6 network is 10.

   5. Run commit

      The configuration is committed.

   Configure the global IS-IS interface cost on IPv6 network.

   1. Run system-view

      The system view is displayed.

   2. Run isis [ process-id ]

      The IS-IS view is displayed.

   3. Run ipv6 circuit-cost cost [ level-1 | level-2 ]

      The global IS-IS interface cost on IPv6 network is configured.

      By default, the configured cost is applicable to all Level-1 and Level-2 IPv6 interfaces. The default cost is 10.

   4. Run commit

      The configuration is committed.

   Enable IS-IS interface to automatically calculate the interface cost on IPv6 network.

   1. Run system-view

      The system view is displayed.

   2. Run isis [ process-id ]

      The IS-IS view is displayed.

   3. Run ipv6 bandwidth-reference value

      The reference value of the bandwidth is configured. By default, the bandwidth reference value is 100 Mbit/s.

   4. Run ipv6 auto-cost enable

      The interface is configured to automatically calculate its cost on IPv6 network.

   5. Run commit

      The configuration is committed.

   The bandwidth reference value set using the ipv6 bandwidth-reference command takes effect only when the cost style is wide or wide-compatible. In this case, the interface cost is calculated using the following formula:

   Cost of each interface = (Bandwidth-reference/Interface bandwidth) × 10

   If the cost-style is narrow, narrow-compatible, or compatible, the cost of each interface is based on costs listed in Table 8-4.

   Table 8-4 Mapping between IS-IS interface costs and interface bandwidth

   Cost	Bandwidth Range
   60	Interface bandwidth ≤ 10 Mbit/s
   50	10 Mbit/s < interface bandwidth ≤ 100 Mbit/s
   40	100 Mbit/s < interface bandwidth ≤ 155 Mbit/s
   30	155 Mbit/s < interface bandwidth ≤ 622 Mbit/s
   20	622 Mbit/s < Interface bandwidth ≤ 2.5 Gbit/s
   10	2.5 Gbit/s < Interface bandwidth