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Known Limitations

Learn about known limitations in Junos OS Release 21.2R3 for EX Series switches.

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

General Routing

  • Junos OS might hang trying to acquire the SMP IPI lock while rebooting when it is running as a VM on Linux and QEMU hypervisor. PR1385970

  • On a virtual chassis, CLI command to add license is not available on the backup member. Licenses must be added from the primary member only. PR1545075

  • Packets mirrored through analyzer with ingress and egress interfaces across different virtual chassis members might have a different VLAN-ID from that of VLAN-ID of the exiting egress interface. This limitation is from underling hardware. PR1552905

  • Resource deadlock avoided messages observed during software add on EX4400 platforms. No functionality impact seen. PR1557468

  • RPD core file is generated when the device reboots and daemon restarts. Daemon recovers and there is no service impact on routing protocol usage PR1567043


  • On EX4400 device, a cloud LED on the device indicates the phone home client states and device connectivity state with the cloud. When the grpc application is configured with non-root user, then, the cloud LED will not display any pattern related to day1 states. The LED pattern will still be displaying the previous day0 state as applicable. PR1589321