Loss of log messages with errors "vmsyslog logger X.X.X.X lost xxx log messages"

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• In /var/log/vmkernel.log you see errors similar to:

2019-01-02T05:29:43.230Z cpu63:66187)ALERT: vmsyslog logger 1xx.1xx.2xx.39:514 lost 83302 log messages

• In /var/log/.vmsyslogd.err you see errors similar to:

2019-01-02T05:29:43.377Z vmsyslog.loggers.file : ERROR ] Failed to spawn onrotate call
Traceback (most recent call last):
File "/build/mts/release/bora-10719125/bora/build/esx/release/vmvisor/sys-boot/lib64/python3.5/site-packages/vmsyslog/loggers/file.py", line 379, in writeLog
File "/build/mts/release/bora-10719125/bora/build/esx/release/vmvisor/sys-boot/lib64/python3.5/subprocess.py", line 676, in __init__
File "/build/mts/release/bora-10719125/bora/build/esx/release/vmvisor/sys-boot/lib64/python3.5/subprocess.py", line 1221, in _execute_child
OSError: [Errno 28] No space left on device
2019-01-02T05:32:13.804Z vmsyslog : CRITICAL] vmsyslogd daemon starting (87201097)
2019-01-02T05:32:14.005Z vmsyslog.main : CRITICAL] Dropping messages due to log stress (qsize = 25000)

Note:The preceding log excerpts are only examples.Date,time and environmental variables may vary depending on your environment.

Environment

VMware vSphere ESXi 6.5

Cause

If the network is slow, the write thread to network buffer will be faster than the reader thread which leads to losing messages.

Resolution

This issue is resolved in VMware vSphere ESXi 6.5 U3 and ESXi 6.7 U3 release.

To download  
Go to Customer Connect for ESXi 6.5 U3
Go to Customer Connect for ESXi 6.7 U3

Additional Information

Refer to VMware KB :  Methods for upgrading an  VMware ESXi host

Impact/Risks:
No Impact.