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Open Issues

Learn about open issues 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.

Class of Service (CoS)

  • On all Junos OS platforms, in a scaled scenario when some of the ge/xe/et interfaces are members of aggregated Ethernet (ae) and the Class of Service (CoS) forwarding-class-set configuration is applied with a wildcard for all the physical interfaces and aaggregated Ethernet, it might trigger a Flexible PIC Concentrators (FPC) crash which leads to traffic loss. PR1688455


  • On all Junos OS and Junos OS Evolved platforms where EVPN feature is enabled, the l2ald process might crash in a rare scenario when a loopback IP address is changed.PR1631280

  • While verifying, show mac-vrf routing database instance User_mvs1 extensive command "mobility-seq-num" is not as expected.PR1694943

General Routing

  • When VLAN is added as an action for changing the VLAN in both ingress and egress filters, the filter is not installed. PR1362609

  • On the QFX5100 line of switches, inserting or removing optics on a port might cause a Packet Forwarding Engine Manager CPU spike and an eventual microcode failure. PR1372041

  • VXLAN VNI (multicast learning) scaling on QFX5110 traffic issue is seen from VXLAN tunnel to Layer 2 interface. PR1462548

  • 5M DAC connected between QFX10002-60C and MX2010 doesn't link up. But with 1M and 3M DAC this interop works as expected. Also it is to be noted QFX10002-60C and ACX or Traffic generator the same 5M DAC works seamlessly. There seems to be certain SI or link level configuration on both QFX10002-60C and MX2010 which needs to be debugged with the help from HW and SI teams and resolved. PR1555955

  • To avoid the additional interface flap , interface hold time needs to be configured . PR1562857

  • On QFX5100, Media type for SFP+-10G-CU1M and SFP-T cables are shown as Fiber. This is only a display issue and no functionality impact is observed.PR1570555

  • On a QFX5120, when you disable a protected link. You may see a delay of 200-400 mSec for the system to react to the disable link event.PR1579931

  • In a fully loaded devices, at times, firewall programming was failing due to scaled prefix configuration with more than 64800 entries. However, this issue is not observed in development setup. PR1581767

  • Management interface speed is displayed as 10G instead of 1G though there is no functionality impact. PR1589942

  • On QFX5110 VC, FPC may gets disconnected with 24K DHCPv6 relay scaling, after the traffic is stopped. "pfe_listener_disconnect" error messages may be seen.PR1594748

  • Pim VxLAN not working on TD3 chipsets enabling VxLAN flexflow after Junos OS Release 21.3R1. Customers Pim VxLAN or data plane VxLAN can use the Junos OS Release 21.3R1. PR1597276

  • On QFX5100, optical power is seen after detached and attached QSFP on disable interface. PR1606003

  • On QFX5120-48Y, when scaled config and baseline configs are loaded multiple times one after other without much wait time in between then traffic or protocols on pure L3 interfaces may behave in undefined/unexpected manner. PR1612973

  • On Junos QFX10k platforms with scaled number of BFD (Bidirectional Forwarding Detection) sessions configured, addition of a new BFD session might cause flapping in newly added session and other existing BFD sessions.PR1621976

  • QFX5110-32Q : Traffic loss seen after renumbering master in VCPR1632565

  • Backup FPC lose their connection to the master when new members are added to the VCF (Virtual Chassis Fabric).PR1634533

  • The bounded delay config feature for IFL is not supported on Pyrite platform. The core is seen only when this config is enabled on the device. PR1634941

  • On all devices running Junos OS or Junos OS Evolved, where this is a high BGP scale with flapping route and the BGP Monitoring Protocol (BMP) collector/station is very slow, the rpd process might crash due to memory pressure.PR1635143

  • When a 100G interface on a QFX5120 is converted to a VC port, the interface stays down as the port is configured as 40G internally. PR1638156

  • On all QFX5100 Virtual Chassis platforms, after the reboot, Virtual Chassis port (VCP) ports may not establish a VCP connection and Cyclic Redundancy Check (CRC) errors are also observed.PR1646561

  • On QFX Series platform, v6 logical interfaces statistics are being derived from the underlying physical interfaces statistics unlike on PTX Series where they are hardware assisted. Therefore, they are not very reliable and are at best, guesstimate. PR1653671

  • After converting access side port from SP style to EP style, MAC-IP learning fails for a host and ARP doesn't get resolved. PR1658657

  • QFX5100-24Q and EX4600 devices Virtual-chassis is in unstable state for 3-7 minutes causing traffic loss. PR1661349

  • On all QFX Series platforms, EVPN Type-5 traffic drops are observed when the device is configured only with Type-5 Virtual Routing and Forwarding (VRF) and without an Integrated Routing and Bridging (IRB) interface. PR1663804

  • When the remote end server/system reboots, QFX5100 platform ports with SFP-T 1G inserted might go into a hung state and remain in that state even after the reboot is complete. This might affect traffic after the remote end system comes online and resumes traffic transmission.PR1665800

  • On QFX5110 platforms with more than one Layer 2 circuit configured, deactivating and activating the l2circuit configurations successively might cause traffic drop on one or more L2 circuits. PR1666260

  • Native VLAN with VLAN rewrite on same interface not supported. PR1671372

  • On QFX5200, after NSSU upgrade for a 4 member Virtual Chassis, FPC might toggle resulting in interfaces going offline. PR1673116

  • On QFX5120 Virtual Chassis with Open vSwitch Database (OVSDB) VxLAN topology, Address Resolution Protocol (ARP) resolution fails if the traffic passes through Virtual Chassis port (VCP) ports. As a result, ARP packets drops. PR1679684

  • On QFX5100 platforms (both stand-alone and VC scenario) running Junos OS, occasionally during the normal operation of the device, Packet Forwarding Engine can crash resulting in total loss of traffic. The Packet Forwarding Engine reboots itself following the crash. PR1679919

  • On all Junos OS platforms, in a scaled scenario when some of the ge/xe/et interfaces are members of aggregated Ethernet and the Class of Service (CoS) forwarding-class-set configuration is applied with a wildcard for all the physical interfaces and aggregated Ethernet, it would trigger a Flexible PIC Concentrators (FPC) crash which leads to traffic loss. PR1688455

  • On all Junos OS platforms, the device control daemon (dcd) process crash is observed when more than 256 VLANs as name tags are added on the same interface.PR1696428

  • On Junos QFX5110 and QFX5120 devices, a small number of packets are lost when assigned VNI (VXLAN Network Identifier) to the VLAN. There is a packet loss on incoming packets, but no packet loss on outgoing packets. PR1697244

Layer 2 Ethernet Services

  • On QFX5100 and QFX5110, vendor-id format might be incorrect for network ports. This does not impact the ZTP functionality or service. The DHCP client configuration is coming from two places, that is, AIU script and vsdk sandbox. The DHCP client configuration coming from AIU script has the serial id in vendor id where as the default configuration from sandbox doesn't have.PR1601504

Layer 2 Features

  • In case of the access-side interfaces used as SP-style interfaces, when a new logical interface is added and if there is already a logical interface on the physical interface, there is 20--50 ms traffic drop on the existing logical interface. PR1367488

  • On QFX5100 and EX4600 platforms, if a change related to TPID is made in the Device Control Daemon, traffic might be dropped in PFE due to failure on l2 learning or interfaces flapping. PR1477156


  • In MVPN Case, if the nexthop index of a group is not same between master and backup after a nsr switchover, we may see a packet loss of 250 to 400 ms. PR1561287

Platform and Infrastructure

  • On all Junos and Junos OS Evolved platforms, while using source-address NTP configuration parameter and issue the command "set ntp date" from the CLI, packets will be sent with the source address of the outgoing interface rather than the manually configured IP address. Typically, the manually configured IP address would be a loopback address. The problem does not apply to automatically generated NTP poll packets.PR1545022

Routing Protocols

  • On Junos OS and Junos OS Evolved platforms configured with graceful-shutdown sender under the BGP dynamic neighborship, the peer device does not receive routes with communities "graceful-shutdown", as it is not advertised by the sender causing the traffic drop for the affected routes. PR1699633