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Known Behavior


This section contains the known behavior, system maximums, and limitations in hardware and software in Junos OS Release 16.2R2 for MX Series and T Series.

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

High Availability (HA) and Resiliency

  • ISSU limitations with MX Series FPCs—Unified ISSU is not supported with Junos OS Release 16.2 for MX Series routers with the following Flexible Port Concentrators (FPCs):

    • MX-MPC2E-3D-NG

    • MX-MPC2E-3D-NG-Q

    • MX-MPC3E-3D-NG

    • MX-MPC3E-3D-NG-Q

    To perform a unified ISSU on a MX Series router with these FPCs installed, reboot the FPCs before completing the unified ISSU process.

    [See Unified ISSU System Requirements]

Interfaces and Chassis

  • Reordering of MAC addresses after a Routing Engine switchover—In Junos OS Release 14.2 and later, if you configure multiple aggregated Ethernet interfaces, the MAC address of the aggregated Ethernet interfaces displayed in the show interfaces ae number command output might get reordered after a Routing Engine switchover or restart.

    As a workaround, you can configure static MAC addresses for aggregated Ethernet interfaces. Any external dependency, such as filtering of the MAC addresses that are assigned before the reboot, becomes invalid if the MAC address changes.

Software Installation and Upgrade

  • On a broadband network gateway (BNG) that is running enhanced subscriber management, you must take the service cards offline before you can perform an in-service software upgrade (ISSU) to Junos OS Release 16.2 from a Junos OS release that includes the application-aware policy control feature (Junos OS Release 16.1R4 and later).