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New and Changed Features


This section describes the new features and enhancements to existing features in Junos OS Release 15.1 for the QFX Series.


The following QFX Series platforms are supported in Release 15.1R7: QFX3500, QFX3600, and QFX5100.


  • Support for YANG features including configuration hierarchy must statement constraints published in YANG, and a module that defines Junos OS YANG extensions (QFX Series)—Starting with Junos OS Release 15.1R3, the Juniper Networks configuration YANG module includes configuration constraints published using either the YANG must statement or the Junos OS YANG extension junos:must. Constraints that cannot be mapped directly to the YANG must statement, which include expressions containing special keywords or symbols such as all, any, unique, $, __, and wildcard characters, are published using junos:must.

    The junos-extension module contains definitions for Junos OS YANG extensions, including the must and must-message keywords. The junos-extension module is bound to the namespace URI and uses the prefix junos. You can download Juniper Networks YANG modules from the Juniper Networks website, or you can generate the modules by using the show system schema operational mode command on your local device.

    [See Using Juniper Networks YANG Modules.]

  • Support for enforcing RFC-compliant behavior in NETCONF sessions (QFX Series)—Starting with Junos OS Release 15.1R3, you can require that the NETCONF server enforce certain behaviors during the NETCONF session by configuring the rfc-compliant statement at the [edit system services netconf] hierarchy level. If you configure the rfc-compliant statement, the NETCONF server explicitly declares the NETCONF namespace in its replies and qualifies all NETCONF tags with the nc prefix. Also, <get> and <get-config> operations that return no configuration data do not include an empty <configuration> element in RPC replies.

    [See Configuring RFC-Compliant NETCONF Sessions.]

Network Management and Monitoring

  • Monitor Virtual Chassis ports (VCPs) with SNMP (QFX3500, QFX3600)—Starting with Junos OS Release 15.1R3, you can configure the switch to monitor VCPs with SNMP. To enable SNMP monitoring of VCPs in a Virtual Chassis or Virtual Chassis Fabric (VCF), use the set virtual-chassis vcp-snmp-statistics CLI command.

Spanning-Tree Protocols

  • Global configuration of spanning-tree protocols (QFX Series)—Starting with Junos OS Release 15.1R13, global configuration of the spanning-tree protocols RSTP, MSTP, and VSTP is supported on QFX Series switches with Enhanced Layer 2 Software (ELS) configuration style.

    In earlier releases, the ELS software supported configuration of spanning-tree protocols on individual interfaces or on a range of interfaces. It did not support configuration of spanning-tree protocols on all interfaces or disabling spanning-tree protocols on specific interfaces.

    Starting with this release, CLI changes in the ELS software provide the options of configuring spanning-tree protocols on all interfaces, disabling the configuration for individual interfaces, and configuring VSTP on all VLANs or on a VLAN group.

    [See Configuring RSTP (CLI Procedure), Configuring MSTP, and Configuring VLAN Spanning-Tree Protocol.]

User Interface and Configuration

  • Support for replacing patterns in configuration data within NETCONF and Junos OS XML protocol sessions (QFX Series)—Starting with Junos OS Release 15.1R3, you can replace variables and identifiers in the candidate configuration when performing a <load-configuration> operation in a Junos OS XML protocol or NETCONF session. The replace-pattern attribute specifies the pattern to replace, the with attribute specifies the replacement pattern, and the optional upto attribute indicates the number of occurrences to replace. The scope of the replacement is determined by the placement of the attributes in the configuration data. The functionality of the attribute is identical to that of the replace pattern configuration mode command in the Junos OS CLI.