Changes in Default Behavior and Syntax in Junos OS Release 12.3X50 for the QFX Series

Interfaces

• In a multichassis link aggregation group (MC-LAG) topology with the Link Aggregation Control Protocol (LACP) configured, the two aggregated Ethernet interfaces in an MC-LAG typically originate on two different QFX Series switches (for example, two QFX3500 switches), and terminate on the same end device, such as a switch or a server. However, in this topology, one or more of the physical links could be incorrectly connected, which could result in the two aggregated Ethernet interfaces in an MC-LAG originating on two different QFX Series switches but terminating on two different end devices. In previous software releases, QFX3500 and QFX3600 switches could not detect an incorrect connection in an MC-LAG topology. In fact, the status of the MC-LAG could appear to be in the up state on both switches.

  The QFX3500 and QFX3600 switches can now detect an incorrect connection in an MC-LAG topology by default. If these switches detect an incorrect connection, the output for the show interfaces mc-ae command displays the Current State Machine’s State as mcae lacp partner mismatch and the Local Status as standby.

  You can optionally disable the detection of an incorrect connection in an MC-LAG topology by entering the no-miswire-detection statement at the [edit interfaces interface-name aggregated-ether-options mc-ae] hierarchy on the two QFX3500 and QFX3600 switches in the topology. To re-enable the detection, delete the miswire-detection statement from the same hierarchy on the two QFX3500 and QFX3600 switches in the topology.

Link Layer Discovery Protocol (LLDP)

• Change in output for the show lldp local-information command on QFX3500 switches—With QFX3500 switches running Junos OS Release 12.2X50 version 4 and higher (excepting Junos OS Release 12.3X50-D35), the Interface description field displays the advertised LLDP description as the interface name (for example, xe-3/0/1.0).

  For QFX3500 switches running Junos OS Release 12.3X50-D35, the Interface description field displays the advertised LLDP description as the user-configured port description (for example, rr7-14-ws-dis-f1-t1-r24).

Junos SDK

• As of Junos OS Release 12.3, Junos OS applications are installed only if the application is built with the same release of the Junos SDK as the Junos OS release on which the application is being installed. For example, an application built with Release 12.3R2 can be installed only on Junos OS Release 12.3R2 and cannot be installed on Junos OS Release 12.3R1, Junos OS Release 12.3R3, or Junos OS Release 13.1R1. The Junos SDK is supported on the QFX3500 switch.

User and Access Management

• Change in output for the show lldp local-information command on QFX3500 switches--With QFX3500 switches running Junos OS Release 12.2X50 version 4 and higher (excepting Junos OS Release 12.3X50-D35), the Interface description field displays the advertised LLDP description as the interface name (for example, xe-3/0/1.0).

  For QFX3500 switches running Junos OS Release 12.3X50-D35, the Interface description field displays the advertised LLDP description as the user-configured port description (for example, rr7-14-ws-dis-f1-t1-r24).

Related Documentation

• New Features in Junos OS Release 12.3X50-D30 for the QFX Series
• New Features in Junos OS Release 12.3X50-D10 for the QFX Series
• Limitations in Junos OS Release 12.3X50 for the QFX Series
• Outstanding Issues in Junos OS Release 12.3X50 for the QFX Series
• Resolved Issues in Junos OS Release 12.3X50 for the QFX Series
• Errata in Documentation for Junos OS Release 12.3X50 for the QFX Series
• Upgrade and Downgrade Instructions for Junos OS Release 12.3 for the QFX Series