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IOS XR Release Strategy and Deployment Recommendation



The purpose of this document is to help you understand the IOS XR software release strategy and help you select the optimal IOS XR release for deployment in your production network. 

This content of this document, including the projected release dates, should be understood only as a guideline. I suggest that you always contact your account team at Cisco to obtain a the IOS XR suggestion for your specific deployment scenario.

Official information on IOS XR releases is available in the "Guidelines for Cisco IOS XR Software"document.

What Is An Extended Maintenance Release (EMR)

For us at Cisco it is very important to deliver the new features and hardware that your network requires, while at the same time maintain the high software quality. We are continuously investing efforts to improve the quality of our software and hardware. We are adjusting our culture, processes and practices to achieve that goal.

One of the key concepts in the software quality plan is the Extended Maintenance Release (EMR) introduced in IOS XR for the first time with the release 4.3.4.

Extended Maintenance Release (EMR) criteria:

  • No new software features
  • No new HW support
  • Incoming bug rate to drop by at least 90% from peak rate for that release.
  • Zero critical bugs.

By choosing the EMR for deployment, you are making the optimal choice. We will be happy to work with you on EMR early field trials or any other way to help synchronise your upgrade/migration plan with the EMR release schedule.


By selecting the EMR you are not only making sure that you are getting the best quality release, you are also selecting a release with the highest deployment rate.


Benefit Of Upgrading To A Most Recent EMR

Software Stability

  • Improved Software Stability:
    • Reduced number of SMU’s and SMU’s that need reboot. 59% Improvement, normalizing by Installed base, in the last 3 years.
    • 42% Improvement on Sev. 1&2 SW defects (2019 Vs. 2017).
  • Improved system debuggability


  • Enhanced Network Availability
  • Reduced Time to Restore
  • Reduced Business Impact and operational costs

Software Quality

  • Improved SW Quality:
    • Reduced Number of SW Incidents 58% Improvement of 6.4.2 Vs. 5.3.3. normalizing SW defects by Installed base (3 Years timeframe)
    • 40% Improvement of 6.4.2 Vs. 5.3.4. (≈ 2 years timeframe)
    • Improved system debuggability


  • Enhanced Operational Excellence
  • Reduced time to Resolution
  • Reduced Operational Cost

Vulnerability Risk:

  • Reduced PSIRT exposure

New functionalities:

  • New Features for new Services



Managing Your IOS XR Install Base

Keeping your IOS XR installation up to date with is very important. We continue providing software patches through Software Maintenance Units (SMUs) and Service Packs (SPs).


Manual SMU and SP install is a thing of the past since the introduction of the CSM Server. CSM Server is a web based server side automation and orchestration framework designed to ease the SW maintenance for all IOS XR platforms. After installing CSM Server 4.0, in-application upgrade is available for keeping your CSM Server application up to date.


To get the glimpse of the CSM Server we highly recommend to watch the _video_. CSM Server distribution comes with a documentation included, but you can also read more about it on _supportforums_.


Another benefit of deploying EMR is that more software patches are available compared to other releases. Number of software patches (SMUs) available per release is directly proportional to the number of our customers running the release. Also, on EMR we try to provide, when technically feasible, SMUs for issues affecting the usability of IOS XR, not only for critical issues directly impacting the services. Service Packs (SPs) are also built more frequently compared to non-EMR releases.


SMU and SP concepts are explained in the "Service Pack Overview for Routers that Run Cisco IOS XR" document.


Service Packs on are built on EMR every 8 weeks. On non-EMR builds are on-demand, but never more frequent than on EMR.


Before the introduction of CSM Server, deriving the optimised SMU list for a given install base was a challenging task. Service Pack (SP) was introduced to deliver on operational simplicity.


On 32-bit IOS XR, SP is a single package that can be installed on the system regardless of the active base packages. For example, if BNG package is not active on the system, all BNG elements in the SP are ignored during SP activation.


On 64-bit IS XR, SP is a tarball containing the optimised set of production SMUs posted to date. User should unpack the tarball and install only the RPMs of interest individually or by re-packaging them into a new tarball. For better alignment to the SP concept, from year 2021 onwards the 64-bit SP will be provided in a form of a Golden ISO image.


If you are using CSM Server to manage your install base, CSM Server optimises the SMU set for you, allows you to define "software profiles" (set of base packages plus SMUs or SP) and allows you to easily install the same profile on multiple nodes. You can also run conformance reports. With this CSM Server functionality, the choice between SMU and SP is really down to a user preference. CSM Server delivers the same operational simplicity for users who prefer SMU over SP or vice versa.

64-bit vs 32-bit IOS XR

The 64-bit flavour of IOS XR is available for ASR9000 starting from XR release 6.1.2. Up to and including IOS XR major release 6.6.x,  there is no different release number for the 32-bit and 64-bit IOS XR. The 64-bit software packages are designated by the 'x64' in the package name (e.g. ASR9K-x64-iosxr-px-6.1.2.tar). Split between 32-bit and 64-bit release numbering starts with IOS XR major release 7.0.x. As a consequence, the 7.x.x releases are available only for 64-bit capable platforms. Support for 32-bit IOS XR on ASR9000 continues with 6.7.x, 6.8.x, etc.


For more information, including the required minimum hardware for running 64-bit IOS XR on ASR 9000 platform, refer to the "Cisco ASR 9000 Series IOS XR 64 Bit Data Sheet".


CSM Server contains a module that seamlessly performs the migration from 32-bit XR to 64-bit XR. We highly recommend you to watch this short demo video.


New IOS XR platforms NCS500, NCS5000 and NCS5500 only support the 64-bit flavour.


Suggestions For Year 2021

Suggested releases for validation and deployment in calendar year 2021/2022 are:

Platform Release Comment
8000 7.3.3

EMR for Cisco 8000. Not planned for other platforms.

ASR9000 7.1.3 / 6.7.3, 7.3.2

64-bit XR:7.1.3

32-bit XR: 6.7.3; A9K-RSP440 must stay with 6.4.2 (EoS-EoL notice)

CRS 6.7.4 6.7.4 was released only for CRS
NCS540 7.2.2, 7.3.2  
NCS560 7.2.2, 7.3.2  
NCS5000 7.1.3, 7.2.2, 7.3.2

7.1.3, 7.3.2 as satellite to ASR9000;

7.2.2 for standalone deployments;

NCS5500 7.2.2, 7.3.2  
NCS6000 7.2.2  
XRv9000 7.2.2, 7.3.2  


The following table shows the IOS XR release schedule planning for year 2021.

IOS XR tentative release schedule

Disclaimer: future release dates and numbers are tentative and may change without notice.

(*) LA == Limited Availability. If you need access to this release please contact your account team at Cisco

Release FCS
7.1.3 EMR
  • Posted.
  • EMR for ASR9000, 64-bit.
6.7.3 EMR
  • Posted.
  • Only ASR9000, 32-bit.
7.2.2 EMR 2021-01-29
  • Posted.
  • Available for all IOS XR platforms except ASR9000.
7.3.1 2021-02-28
  • Posted.
  • Available for 8000, ASR9000, NCS5500, XRv9000, NCS540, NCS560, NCS1001, NCS1002, NCS1004.
  • NCS5000 only as ASR9000 satellite.
7.3.2 EMR 2021-Q3
  • Planned for 8000, ASR9000, NCS5500, XRv9000, NCS540, NCS560, NCS1001, NCS1002, NCS1004.
  • NCS5000 only as ASR9000 satellite.
  • EMR for all listed platforms except 8000.
7.3.3 EMR 2021-Q3
  • EMR for Cisco 8000.
  • Not planned for other platforms.
7.4.1  2021-Q2 / 2021-Q3
  • Planned for ASR9000, NCS5500, NCS5700, NCS560, NCS5K (only as Satellite), XRv9000
6.8.1 2021-Q2 / 2021-Q3
  • ASR9000 32-bit only; equivalent of 7.4.1.
7.4.2 2022-Q1
  • Planned EMR for ASR9000, NCS5500, NCS5700, NCS560, NCS5K (only as Satellite), XRv900
6.8.2 2022-Q1
  • ASR9000 32-bit only; equivalent of 7.4.2.


We hope you find this document useful. Happy roll-out of IOS XR!


Related Documentation


Aleksandar Vidakovic
Cisco Employee



hi Andrés,


I'm doing well, thank you. I hope you're doing fine as well.


There will be 6.7.3 and it will be an EMR release. It's scheduled for the end of this calendar year or early in the next one. If that is too far out for you and you don't specifically need any of the 6.7 features, you can go with 6.6.3. It's also an EMR and the field quality markers are also good.




I see that 6.4.3 is the suggested release for the Cisco CRS. Is it also an EMR ?


Aleksandar Vidakovic
Cisco Employee

hi @DavideL3 ,


It is also an EMR, but it's available only for CRS.




Hey Aleksandar,


Will either 7.1.2 or 7.2.1 be a EMR release for the NCS 540? I believe right now its only 7.0.2.

Aleksandar Vidakovic
Cisco Employee

hi@Phobeus ,


7.1.2 is an EMR for all supported platforms, except ASR9000. For ASR9000 the EMR will be 7.1.3.




Hi Aleksandar, 


thank yor for the info. When can we expect 7.1.3?

And what about 32-bit ASR9000, will there also be 6.7.3?





Aleksandar Vidakovic
Cisco Employee

hi  @dfischer_de ,


I'm not in a position to give you a precise date for 7.1.3 and 6.7.3, so I can only say that it will either be end of this year or early next year. Both will be available only for ASR9000 and will be EMRs. If you have very specific plans for this release and would like to be in closer contact with us regarding the early field trial and posting, please have your account team at Cisco reach out to me.






I am planning to upgrade ASR9904. Is there any reason to go to 6.7.3 instead of 6.6.3 if I dont need new features from 6.7.x?

There are no listed caveats in 6.6.3 documentation.

I have MOD160 so 64-bit version is not a option.

What is a recomended version?



Aleksandar Vidakovic
Cisco Employee



hi Ivan,


Happy New Year!


Release 6.6.3 is of a good quality. If you have already completed the 6.6.3 qualification and want to deploy it, go ahead. 


If you are yet to start the qualification, I would suggest to go with 6.7.3 because:

  1. 6.7.3 is the most recent Extended Maintenance Release for ASR9000 and hence our suggestion for deployment.
  2. Even if you don't need new features compared to 6.6.3, release 6.7.3 will reach the End Of SW Maintenance some 14 months later than 6.6.3.
  3. In addition, it contains fixes for some bugs that are applicable to 6.6.3 as well.







Do I understand it correctly that asr9k with 7.1.3 is still an eXR with containers and this "asr9k XR version 7.x.x" has nothing common with "XR7"?

And second question - is FPD autoupgrade mandatory for version upgrade on both asr9901 and asr9001?



Robert Szabo

Hello Alexsandar,


Thanks for the great article! I wondering if you will update with new suggestions for 2021 as well?


We are targeting to go with 6.7.2 this year for our ASR9910's because of ISSU support which is not available in 7.x releases by intention.

I've checked 6.7.3 which you advised that is the EMR code, but on release notes I see no new features, no bugs fixed - so no difference to 6.7.2 at all.


Please advise.



Robert Szabo

Aleksandar Vidakovic
Cisco Employee
Hi Agris,

ASR9k is running the 64-bit XR (aka eXR) which is VM-based. XR7 is has a different architecture and it's available on Cisco 8000 Routers. Note that the platform independent features share the same source code across all XR flavours.

Aleksandar Vidakovic
Cisco Employee
Hi Robert,

Thank you for the nice feedback. I have updated the page with the recommendations for this year.

6.7.3 does contain quite a number of bug fixes compared to 6.7.2. We typically don’t publish this listing because it contains hundreds of fixes and not all of them are externally visible. Between 6.7.2 and 6.7.3, the latter is definitely a better choice.


SDR on CRS-8 with DRP is still supported on lastest IOS XR release for CRS ?
I know that DRP are EoL/EoS but on 6.4.X release documentation I found that are still supported. However using 6.4.3 (or 6.4.2 with SMUs) and mpls pie activated the DRP becomes unstable after first redundancy switchover (policymgr_rp crash with signal 6).
Witch version could be used with SDR+DRP ?




Hi Expert

XRv9000 support PLR (Permanent License Reservation)?

which release?

how can I order that?

Can someone explain from what version of IOS XR and for ASR 9000 routers, PLR licensing could be used ?

Can someone share License Reservation Support Roadmap for IOS XR (XRv9000 and ASR9K)?

How can order SR-PCE on XRv9000?


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