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What’s Changed in Release 21.4R1


  • Output for the show Ethernet switching flood extensive command—The output for the show ethernet-switching flood extensive command now displays the correct next-hop type for Virtual Ethernet and WAN mesh group in an EVPN-VXLAN network as unilist. Previously, the output for the show ethernet-switching flood extensive command would misidentify the next-hop type as composite.

General Routing

  • In Junos OS Release 21.4R1 and later, ssh is enabled by default on all the routers with VM host support.

  • Enhancement to the request system license add terminal command (PTX10001-36MR)—When you run the request system license add terminal command, you can now view following additional fields for information: JUNOS564022985: Ignoring unknown feature.

    [See Managing vMX Licenses.]

  • A major alarm is raised (PTX10008)—A major alarm is raised when a fan tray controller is removed from the chassis.

  • SNMP MIB support for field-replaceable unit (FRU) LEDs (PTX10008)—SNMP MIB object jnxLEDEntry now indicates multiple LED indexes and color values for FRUs.

Interfaces and Chassis

  • When configuring multiple flexible tunnel interface (FTI) tunnels, the source and destination address pair needs to be unique only among the FTI tunnels of the same tunnel encapsulation type. Previously, the source and destination address pair had to be unique across all encapsulation type.

Junos OS API and Scripting

  • Limits increased for the max-datasize statement (ACX Series, PTX Series, and QFX Series)—The max-datasize statement's minimum configurable value is increased from 23,068,672 bytes (22 MB) to 268,435,456 bytes (256 MB), and the maximum configurable value is increased from 1,073,741,824 (1 GB) to 2,147,483,648 (2 GB) for all script types. Furthermore, if you do not configure the max-datasize statement for a given script type, the default maximum memory allocated to the data segment portion of a script is increased to 1024 MB. Higher limits ensure that the device allocates a sufficient amount of memory to run the affected scripts.

    [See max-datasize.]

Network Management and Monitoring

  • SNMP support for MIB—Operational command show snmp mib walk systemnow shows the latest software version and does not show the build date.

    [See show snmp mib.]

  • Support for disconnecting unresponsive NETCONF-over-SSH clients (ACX Series, PTX Series, and QFX Series)—You can enable devices to automatically disconnect unresponsive NETCONF-over-SSH clients by configuring the client-alive-interval and client-alive-count-max statements at the [edit system services netconf ssh] hierarchy level. The client-alive-interval statement specifies the timeout interval in seconds, after which, if no data has been received from the client, the device requests a response. The client-alive-count-max statement specifies the threshold of missed client-alive responses that triggers the device to disconnect the client, thereby terminating the NETCONF session.

    [ See ssh (NETCONF).]

  • The configuration accepts only defined identity values for nodes of type identityref in YANG data models (ACX Series, PTX Series, and QFX Series)—If you configure a statement that has type identityref in the corresponding YANG data model, the device accepts only defined identity values (as defined by an identity statement) as valid input. In earlier releases, the device also accepts values that are not defined identity values.

Routing Protocols

  • To achieve consistency among resource paths, the resource path//mpls/signalling-protocols/segment-routing/aggregate-sid-counters/aggregate-sid-counter ip-addr='address'/state/countersname='name'/out-pkts/ is changed to /mpls/signaling-protocols/segment-routing/aggregate-sid-counters/aggregate-sid-counterip-addr='address'/state/counters name='name'/. The leaf "out-pkts" is removed from the end of the path, and "signalling" is changed to "signaling" (with one "l").