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What's Changed

Learn about what changed in this release for ACX Series routers.


  • Support for configuring multi-chassis protection at the global level (ACX7509)— We've enabled the multi-chassis-protection statement at the edit multi-chassis global hierarchy level for ACX7509 devices. In earlier releases, multi-chassis-protection could only be enabled at the interface level.

  • Flow-label configuration status for EVPN ELAN services— The output for the show evpn instance extensive command now displays the flow-label and flow-label-static operational status for a device and not for the routing instances. A device with flow-label enabled supports flow-aware transport (FAT) flow labels and advertises its support to its neighbors. A device with flow-label-static enabled supports FAT flow labels but does not advertise its capabilities.

General Routing

  • Prior to this change when route sharding is configured the output of CLI show route commands included information about sharding. After the change the use must add the rib-sharding all argument to CLI show route commands to display sharding information.

  • sFlow configuration? sFlow configuration is allowed only on et, xe, and ge interfaces in EVO-based platforms. All other interfaces are blocked for configuring sFlow on EVO platforms. A cli error will be thrown if sFlow is configured on any other interface other than et, xe or ge interface.

  • The Ethernet link fault management process (lfmd) runs only when the link-fault-management protocol is configured.

  • The traffic rate could display incorrect values in the show services inline ip-reassembly statistics fpc x pfe-slot y output.

Juniper Extension Toolkit (JET)

  • Python 3 is the default and only Python version for executing Juniper Extension Toolkit Python scripts (ACX Series, PTX Series, and QFX Series)—Junos OS Evolved supports only Python 3 for executing Juniper Extension Toolkit (JET) scripts written in Python. Python 2.7 is no longer supported for executing JET scripts, and we've deprecated the language python statement at the [edit system scripts] hierarchy level.

    [See Understanding Python Automation Scripts for Junos Devices.]

Junos OS API and Scripting

Network Management and Monitoring

  • Junos YANG modules for RPCs include the junos:command extension statement (ACX Series, PTX Series, and QFX Series)—The Junos YANG modules that define RPCs for operational mode commands include the junos:command extension statement in schemas emitted with extensions. The statement defines the CLI command for the corresponding RPC. The Juniper yang GitHub repository stores the RPC schemas with extensions in the rpc-with-extensions directory for the given release and device family. Additionally, when you configure the emit-extensions statement at the [edit system services netconf yang-modules] hierarchy level and generate the YANG schemas on the local device, the YANG modules for RPCs include the junos:command extension statement.

Platform and Infrastructure

  • Internal Python tools and scripts use Python 3 (ACX7100-32C, ACX7509, PTX10001-36MR, PTX10003, PTX10004, PTX10008, PTX10016, QFX5130-32CD, and QFX5220)—Junos OS Evolved uses Python 3 for all internal Python tools and scripts, but there is no change in functionality on the device.

System Management

  • When disk usage for the run directory is above 85%, ZooKeeper logs and snapshots in the /run/zookeeper/conf/default/version-2 directory will be deleted if there are more than 3 files, leaving only the 3 most recent files.

User Interface and Configuration

  • Changes to the JSON encoding of configuration data for YANG leaf nodes of type identityref (ACX Series, PTX Series, and QFX Series)—If a YANG leaf node is type identityref, Junos devices emit the namespace-qualified form of the identity in the JSON encoding of that node. In addition, Junos devices accept both the simple (no namespace) and the namespace-qualified form of an identity in JSON configuration data. In earlier releases, Junos devices only emit and accept the simple form of an identity. Emitting and accepting the namespace-qualified identity ensures that the device can properly resolve the value in the event that the YANG data model defines an identity and a leaf node containing the identifyref value in different modules.

  • The file copy command supports only text-formatted output in the CLI (ACX Series, PTX Series, and QFX Series)—The file copy command does not emit output when the operation is successful and supports only text-formatted output when an error occurs. The file copy command does not support using the | display xml filter or the | display json filter to display command output in XML or JSON format in any release. We've removed these options from the CLI.