segment-routing global-block (IS-IS view)

Function

The segment-routing global-block command configures a segment routing global block (SRGB).

The undo segment-routing global-block command deletes an SRGB.

By default, no SRGB is configured.

Format

segment-routing global-block begin-value end-value [ ignore-conflict ]

undo segment-routing global-block [ begin-value end-value [ ignore-conflict ] ]

Parameters

Parameter Description Value
begin-value

Specifies the beginning value of Segment Routing global block (SRGB).

The value changes dynamically, depending on the actual situation of the equipment.

end-value

Specifies the end value of Segment Routing global block (SRGB).

The value changes dynamically, depending on the actual situation of the equipment.

ignore-conflict

Flag indicating that a label conflict is ignored.

-

Views

IS-IS view

Default Level

2: Configuration level

Task Name and Operations

Task Name Operations
isis write

Usage Guidelines

Usage Scenario

To configure an SRGB in an existing IGP instance, run the segment-routing global-block command.

Prerequisites

Configure IS-IS process first.

Enable the segment-routing in system-view.

Precautions

  1. If this command is not run, SR cannot work properly, but all SR configurations can be properly performed.
  2. Before modifying an SRGB, run the undo segment-routing global-block command to delete the SRGB configuration. This operation causes service flapping.
  3. The next hop of an SR route cannot recurse to a tunnel interface. As such, if the current IS-IS process has been enabled on an FA tunnel interface and an SRGB needs to be configured, SR labeled traffic may be discarded.
  4. This command does not support IS-IS multi-topology.
  5. The configuration with the ignore-conflict parameter does not take effect immediately. You need to restart the device to make the configuration take effect. If some labels in the configured SRGB are occupied, you can configure the ignore-conflict parameter and restart the device to deliver the configuration. However, this operation is not recommended in normal cases. You can run the display isis brief command to check whether ignore-conflict is configured for the SRGB and whether related TLVs are advertised after the device restart.

Example

# Configure an SRGB in an existing IS-IS instance. (The value range of SRGB changes dynamically, depending on the actual situation of the equipment. Here is an example only.)
<HUAWEI> system-view
[~HUAWEI] segment-routing
[*HUAWEI-segment-routing] quit
[*HUAWEI] isis 1
[*HUAWEI-isis-1] cost-style wide
[*HUAWEI-isis-1] segment-routing mpls
[*HUAWEI-isis-1] segment-routing global-block 153616 153800
# If one or more labels in an SRGB being configured are occupied, you can specify the ignore-conflict parameter in an attempt to deliver the SRGB configuration. However, this configuration takes effect only after the device is restarted.
<HUAWEI> system-view
[~HUAWEI] segment-routing
[*HUAWEI-segment-routing] quit
[*HUAWEI] isis 1
[*HUAWEI-isis-1] cost-style wide
[*HUAWEI-isis-1] segment-routing mpls
[*HUAWEI-isis-1] segment-routing global-block 153616 153800 ignore-conflict
Copyright © Huawei Technologies Co., Ltd.
Copyright © Huawei Technologies Co., Ltd.
< Previous topic Next topic >