This article explains the cause for the reported syslog message.

On JUNOS release prior to 20.2R3, all QFX5K platforms with EVPN VXLAN scenario may expience memory leak when DHCP configuration was enabled. The following syslog message will be observed when the memory leak is taking place, and corresponding syslog message can be used as indicator of hitting on known software PR#1566483

Nov 17 21:38:31.135 rsw34.ebo : %PFE-3: fpc0 TX VxLAN BCAST: vport NULL for ifl_index 559

This software defect has been fixed in JUNOS release 20.2R3, 20.3R3, 20.4R2, 21.1R1, 21.1R2, 21.2R1, 20.2R2-S3 and newer code.

However, the same syslog message is perserved to provide debugging information. In such situation, if the network port goes down due to the BGP EVPN session goes down, the vport associated with the vtep will be deleted in PFE hence VPORT will be NULL for the corresponding network side interface in PFE. Once VTEP/VPORT comes up (Network interface in VxLAN associated with BGP), the logs should not be seen.

Due to above reason, on JUNOS release 20.2R3, 20.3R3, 20.4R2, 21.1R1, 21.1R2, 21.2R1, 20.2R2-S3 and newer code, the syslog message is informational only and does not indicate any system malfunction, and can be safely ignored.

This log message does not indicate any service impact and can be safely ignored. It is expected to see the log message if QFX5k EVPN BGP session goes down for network event.

To suppress repeating non-impacting messages, refer to KB9382 [juniper.net] - How to prevent certain syslog messages from being written to the log file

initial KB draft version 1.0 by Peter Zhang