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Known Limitations

Learn about known limitations in Junos OS Release 21.4R3 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

  • QFX10K:Source MAC and TTL values are not updated for routed multicast packets in EVPN-VXLAN PR1346894

  • On the QFX5000 line of switches, there might be a significant difference between the configured rate and the actual rate with storm control configuration. This is due to hardware limitations and their internal calculation on rate limits. PR1526906

  • On QFX5200 and QFX5100 switches with the IPIP tunnel feature, "show dynamic-tunnels database statistics" command output shows extra packet counts (i.e. sampled packets when sFlow is enabled). PR1555922

  • Once vxlan is configured on an IFD, its always treated as vlxan port even though L2 vlan exists.PR1570689

  • On QFX5k/EX46xx, IRACL filters will not be able to match on VxLAN tunnel terminated packets. PR1594319

  • The 1PPS performance is failing when PTP slave is connected via a copper port. 1PPS is an electrical output from the router that is used for test purposes. The packet time error confirmed to be passing on copper port so this issue doesn't impact network time delivery. PR1618533

  • When IFA2.0 Init feature enabled on switch and flows are sampled, we will see incorrect pps and bps stats at IFL level on ingress and egress ports. PR1620139

  • minimal traffic loss can be expected if the number of interfaces in ae and could see slight increase if the number of interfaces in ae is increased but the drop is inconsistent and the packet drop would be expected around ~0.0001%. PR1629661

  • Unified ISSU on QFX5120-48Y and EX4650 switches will not be supported if there is a change in the Cancun versions of the chipset SDKs between the releases. This is a product limitation as change in the Cancun firmware leads to the chip reset and hence ISSU is impacted. The Cancun versions in the chipset SDKs should be the same between two JUNOS OS releases for ISSU to work. PR1634695

  • Release note needed PR1647773


  • While upgrading the image from 21.2T to 21.3DCB, the no-validate knob is mandatory for the upgrade command to proceed. PR1586481