ramdisk full due to vsantraces and running vSAN File Services

Products

• VMware vSAN

Issue/Introduction

Symptoms:
In vobd.log you see:
2021-04-10T11:37:00.295Z: [VisorfsCorrelator] 3257982723401us: [vob.visorfs.ramdisk.full] Cannot extend visorfs file /vsantraces/vsantraces--2021-04-10T11h21m29s968.gz because its ramdisk (vsantraces) is full.
2021-04-10T11:37:00.295Z: [VisorfsCorrelator] 3257967831661us: [esx.problem.visorfs.ramdisk.full] The ramdisk 'vsantraces' is full.  As a result, the file /vsantraces/vsantraces--2021-04-10T11h21m29s968.gz could not be written.

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

vSAN File Services is enabled

Environment

VMware vSAN 7.0.x

Cause

Under certain conditions, some vsantrace entries may be logged too frequently, eventually exhausting the capacity of the volume holding the trace files.

Resolution

Upgrade both vCenter/ESXi versions to 7.0U2 or higher

Workaround:
Follow KB The ramdisk 'vsantraces' is full to either redirect vsantaces to a syslog server or limit vsantraces on the ramdisk to 200MB.

Additional Information

Impact/Risks:
ramdisk gets full which could lead to a hung host or the host becoming non-responsive in vCenter