Help us improve your experience.

Let us know what you think.

Do you have time for a two-minute survey?

Junos OS Release Notes for JRR Series


These release notes accompany Junos OS Release 20.4R3 for the JRR Series. They describe new and changed features, limitations, and known and resolved problems in the hardware and software.

You can also find these release notes on the Juniper Networks Junos OS Documentation webpage, located at

What's New

Learn about new features introduced in the Junos OS main and maintenance releases for JRR Series Route Reflectors.

What's New in Release 20.4R3

There are no new features or enhancements to existing features for JRR Series in Junos OS Release 20.4R3.

What's New in Release 20.4R2

There are no new features or enhancements to existing features for JRR Series in Junos OS Release 20.4R2.

What's New in Release 20.4R1

Routing Protocols

  • Support for BGP Sharding (JRR200)—Starting in Junos OS Release 20.4R1, we support BGP sharding. BGP sharding splits a BGP RIB into several sub RIBs and each sub RIB handles a subset of BGP routes. Each sub RIB is served by a separate RPD thread to achieve parallel processing. This results in reduced convergence time and faster performance. BGP sharding is disabled by default.

    To enable BGP sharding, configure rib-sharding at the [edit system processes routing bgp] hierarchy level. Sharding is dependent on the update I/O thread feature. Therefore, you need to enable update I/O thread when you configure sharding. To enable update I/O, configure update-threading at the [edit system processes routing bgp] hierarchy level for rib-sharding configuration to pass commit check.

    If you configure rib-sharding on a routing engine, RPD will create sharding threads. By default the number of sharding and update threads created is same as the number of CPU cores on the routing engine. Optionally, you can specify the number-of-shards and number-of-threads you want to create.


    BGP sharding is supported for IPv4, IPv6, L3VPN and BGP-LU. All the other RIBs are processed without sharding.

    [See rib-sharding and update-threading.]

What's Changed

There are no changes in behavior and syntax in Junos OS Release 20.4R3 for JRR Series Route Reflectors.

Known Limitations

Learn about known limitations in this release for JRR200 Route Reflectors.

Routing Protocols

  • These features are not supported in Junos OS 20.4R1 release for BGP Sharding:

    • routing-options validations with rib sharding

    • inet4/6 unicast rib-group along with rib sharding

    • outbound route-filter with bgp sharding.

Open Issues

There are no open issues in this release for JRR Series Route Reflectors.

Resolved Issues

This section lists the issues fixed in Junos OS Release 20.4R3 for JRR Series routers.

For the most complete and latest information about known Junos OS defects, use the Juniper Networks online Junos Problem Report Search application.

Resolved Issues: 20.4R3

General Routing

  • JRR200: Option-60 (Vendor-Class-Identifier) is not sent during ZTP. PR1582038

Resolved Issues: 20.4R2

There are no fixed issues in the Junos OS Release 20.4R2 for JRR Series routers.

Resolved Issues: 20.4R1

General Routing

  • On the JRR200 routers, the firewall filter with non-zero TTL value might cause a commit error. PR1531034

  • tcp_timer_keep logs flood on JRR200. PR1533168

  • Optics info of physical interfaces is not available for JRR200 on Junos OS. PR1537261

  • The CLI "request system power-off" and "request system halt" commands do not work as expected on JRR200. PR1534795

Documentation Updates

There are no errata or changes in Junos OS Release 20.4R3 documentation for JRR200 Route Reflectors.

Migration, Upgrade, and Downgrade Instructions

This section contains the upgrade and downgrade support policy for Junos OS for the JRR Series Route Reflector. Upgrading or downgrading Junos OS might take several minutes, depending on the size and configuration of the network.

For information about software installation and upgrade, see the JRR200 Route Reflector Quick Start   and the Installation and Upgrade Guide.

Upgrade and Downgrade Support Policy for Junos OS Releases

Support for upgrades and downgrades that span more than three Junos OS releases at a time is not provided, except for releases that are designated as Extended End-of-Life (EEOL) releases. EEOL releases provide direct upgrade and downgrade paths—you can upgrade directly from one EEOL release to the next EEOL release even though EEOL releases generally occur in increments beyond three releases.

You can upgrade or downgrade to the EEOL release that occurs directly before or after the currently installed EEOL release, or to two EEOL releases before or after. For example, Junos OS Releases 19.2, 19.3, and 19.4 are EEOL releases. You can upgrade from Junos OS Release 19.2 to Release 19.3 or from Junos OS Release 19.2 to Release 19.4.

You cannot upgrade directly from a non-EEOL release to a release that is more than three releases ahead or behind. To upgrade or downgrade from a non-EEOL release to a release more than three releases before or after, first upgrade to the next EEOL release and then upgrade or downgrade from that EEOL release to your target release.

For more information about EEOL releases and to review a list of EEOL releases, see