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Known Limitations

Learn about known limitations in this release for QFX 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 can hang while trying to acquire the SMP IPI lock while rebooting when it is running as a VM on Linux and QEMU hypervisor. PR1385970

  • Error logs are expected when routes point to the target next hop, which in turn point to hold next hops. These error logs are present for a short time. Later, when the next hop changes from a hold next hop to valid next hop, unilist next hops will be walked again and updated with the appropriate weight and reroute counters, and no more error logs will be seen. PR1387559

  • On QFX10000 line of switches, the analyzer does not mirror after adding the child member to an aggregated Ethernet interface. PR1417694

  • Changing the scaled firewall profiles on the fly does not release the TCAM resources as expected. PR1512242

  • On QFX5200 and QFX5100 switches with the IP-IP tunnel feature, the show dynamic-tunnels database statistics command output shows extra packets counts. That is, sampled packets when sFlow is enabled. PR1555922

  • On QFX5000, in EVPN_VXLAN deployment, BUM (Broadcast, Unknown Unicast, and Multicast) traffic replication over VTEP might send out more packets than expected. PR1570689

  • On QFX5120 switches, IRACL filters might not be able to match on VXLAN tunnel terminated packets. PR1594319

  • On QFX5100 switches, the overall device utilization and FPC CPU utilization might be high in case of 4093 Irb with full port density (32/24). It might differ by maximum 4-5 percent compare to the same system having very less port density (1 or 2 ports). Some of the FPC threads takes more CPU in such scenario (for example, Ethernet and QSFP). PR1595029

  • sFlow in an EVPN VXLAN IPv4 underlay, outgoing interface (OIF) will be reported as zero for ingress sampling when packet goes out through ECMP next hops. PR1608121


  • To upgrade to Junos OS Release 21.2R1, you need to include the no-validate option when issuing the upgrade command.

    Junos OS releases prior to 20.4R1 do not support the no-validate option with unified ISSU. In order to upgrade from an older release to Junos OS Release 21.2R1 with unified ISSU, you must first upgrade to a release that supports the no-validate option for unified ISSU, such as Junos OS Release 20.4R1. PR1568757

  • Junos OS Release 21.1 and earlier are running on FreeBSD version 11 whereas from Junos OS Release 21.2 onward, the FreeBSD version is 12. Software upgrade to Junos OS Release 21.2 or later from Junos OS Release 21.1 or earlier will mandatorily need CLI configuration statement no-validate during software image upgrade process. PR1586481