Preface

From Release 6.1.2 onwards, Cisco introduces support for the 64-bit Linux-based IOS XR operating system. Extensive feature parity is maintained between the 32-bit and 64-bit environments. Unless explicitly marked otherwise, the contents of this document are applicable for both the environments. For more details on Cisco IOS XR 64 bit, refer to the Release Notes for Cisco ASR 9000 Series Routers, Release 6.1.2 document.

The Segment Routing Configuration Guide for Cisco ASR 9000 Series Aggregation Services Routers preface contains these sections:

Changes to This Document

This table lists the changes made to this document since it was first printed.

Date

Change Summary

June 2026

Republished with feature updates for Release 26.2.1.

February 2026

Initial release of this document.

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