auto-cost enable (IS-IS view)

Function

The auto-cost enable command enables IS-IS to automatically calculate the link cost of interfaces according to the interface bandwidth.

The auto-cost enable compatible command enables IS-IS to automatically calculate the link cost of interfaces according to the interface bandwidth in compatible.

The undo auto-cost enable command disables the function.

The ipv6 auto-cost enable command enables IS-IS to automatically calculate the IPv6 link cost of interfaces according to the interface bandwidth.

The ipv6 auto-cost enable compatible command enables IS-IS to automatically calculate the link cost of interfaces according to the interface bandwidth in compatible.

The undo ipv6 auto-cost enable command disables the function.

By default, automatic interface cost calculation is disabled.

Format

auto-cost enable [ compatible ]

ipv6 auto-cost enable [ compatible ]

undo auto-cost enable

undo ipv6 auto-cost enable

Parameters

None

Views

IS-IS view

Default Level

2: Configuration level

Task Name and Operations

Task Name Operations
isis write

Usage Guidelines

Usage Scenario

You can configure a link cost for interfaces or run the auto-cost enable command to enable automatic interface cost calculation.

You can configure an IPv6 link cost for interfaces or run the auto-cost enable command to enable automatic interface cost calculation.

Prerequisites

No interface cost has been set in the interface view, and no global cost has been configured in the IS-IS view.

Configuration Impact

After automatic interface cost calculation is enabled, the system automatically calculates the interface cost.

If the cost style of the system is wide or wide-compatible:

When auto-cost enable command is configured, Interface cost = (Bandwidth-reference/Interface bandwidth) x 10.

When auto-cost enable compatible command is configured, Interface cost = (Bandwidth-reference/Interface bandwidth).

If the cost type is narrow, narrow-compatible, or compatible, the cost of each interface is based on:

  • Interface bandwidth ≤ 10 Mbit/s, cost = 60
  • 10 Mbit/s < interface bandwidth ≤ 100 Mbit/s, cost = 50
  • 10 Mbit/s < interface bandwidth ≤ 155 Mbit/s, cost = 40
  • 155 Mbit/s < interface bandwidth ≤ 622 Mbit/s, Cost = 30
  • 622 Mbit/s < Interface bandwidth ≤ 2.5 Gbit/s, cost = 20
  • 2.5 Gbit/s < interface bandwidth, Cost = 10

    After automatic interface cost calculation is enabled, the system automatically calculates the interface cost.

    If the cost style of the system is wide or wide-compatible:

    When ipv6 auto-cost enable command is configured, Interface cost = (Bandwidth-reference/Interface bandwidth) x 10.

    When ipv6 auto-cost enable compatible command is configured, Interface cost = (Bandwidth-reference/Interface bandwidth).

    If the cost type is narrow, narrow-compatible, or compatible, the IPv6 link cost of each interface is calculated based on:
  • Interface bandwidth ≤ 10 Mbit/s, cost = 60
  • 10 Mbit/s < interface bandwidth ≤ 100 Mbit/s, cost = 50
  • 10 Mbit/s < interface bandwidth ≤ 155 Mbit/s, cost = 40
  • 155 Mbit/s < interface bandwidth ≤ 622 Mbit/s, Cost = 30
  • 622 Mbit/s < Interface bandwidth ≤ 2.5 Gbit/s, cost = 20
  • 2.5 Gbit/s < interface bandwidth, Cost = 10

Precautions

The auto-cost enable command cannot change the cost of a loopback interface.

The auto-cost enable command can be run on Eth-Trunk interfaces as well as on physical interfaces. If the command is run on an Eth-Trunk interface, the bandwidth of the Eth-Trunk interface is equal to the total bandwidth of all its member interfaces.

If the command is run in the IS-IS view, it takes effect only in the base topology. If the command is run in the IS-IS topology view, it takes effect only in the current topology.

Example

# Enable automatic cost calculation on IS-IS interfaces.
<HUAWEI> system-view
[~HUAWEI] isis 1
[*HUAWEI-isis-1] auto-cost enable
# Enable automatic IPv6 cost calculation on an IS-IS interface.
<HUAWEI> system-view
[~HUAWEI] isis 1
[*HUAWEI-isis-1] ipv6 enable
[*HUAWEI-isis-1] ipv6 auto-cost enable
Copyright © Huawei Technologies Co., Ltd.
Copyright © Huawei Technologies Co., Ltd.
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