VMkernel Observations (VOBs) are system events that you can use to set up vSAN alarms.

vSAN alarms are used for monitoring and troubleshooting performance and networking issues in the vSAN cluster. In vSAN, these events are known as observations.

VMware ESXi Observation IDs for vSAN

Each VOB event is associated with an identifier (ID). Before you create a vSAN alarm in the vCenter Server, you must identify an appropriate VOB ID for the vSAN event for which you want to create an alert. You can create alerts in the VMware ESXi Observation Log file ( vobd.log). For example, use the following VOB IDs to create alerts for any device failures in the cluster.
  • esx.problem.vob.vsan.lsom.diskerror
  • esx.problem.vob.vsan.pdl.offline

To review the list of VOB IDs for vSAN, open the vobd.log file located on your ESXi host in the /var/log directory. The log file contains the following VOB IDs that you can use for creating vSAN alarms.

Table 1. VOB IDs for vSAN
VOB ID Description

esx.audit.vsan.clustering.enabled

The vSAN clustering service is enabled.

esx.clear.vob.vsan.pdl.online

The vSAN device has come online.

esx.clear.vsan.clustering.enabled

The vSAN clustering service is enabled.

esx.clear.vsan.vsan.network.available

vSAN has one active network configuration.

esx.clear.vsan.vsan.vmknic.ready

A previously reported vmknic has acquired a valid IP.

esx.problem.vob.vsan.lsom.componentthreshold

vSAN reaches the near node component count limit.

esx.problem.vob.vsan.lsom.diskerror

A vSAN device is in a permanent error state.

esx.problem.vob.vsan.lsom.diskgrouplimit

vSAN fails to create a disk group.

esx.problem.vob.vsan.lsom.disklimit

vSAN fails to add devices to a disk group.

esx.problem.vob.vsan.lsom.diskunhealthy vSAN disk is unhealthy.

esx.problem.vob.vsan.pdl.offline

A vSAN device is offline.

esx.problem.vsan.clustering.disabled

vSAN clustering services are not enabled.

esx.problem.vsan.lsom.congestionthreshold

vSAN device memory or SSD congestion has been updated.

esx.problem.vsan.net.not.ready

A vmknic is added to vSAN network configuration without a valid IP address. This happens when the vSAN network is not ready.

esx.problem.vsan.net.redundancy.lost

The vSAN network configuration does not have the required redundancy.

esx.problem.vsan.no.network.connectivity

vSAN does not have existing networking configuration, which is in use.

esx.problem.vsan.vmknic.not.ready

A vmknic is added to the vSAN network configuration without a valid IP address.

esx.problem.vob.vsan.lsom.devicerepair

The vSAN device is offline and in a repaired state because of I/O failures.
esx.problem.vsan.health.ssd.endurance One or more vSAN disks exceed the warning usage of estimated endurance threshold.

esx.problem.vsan.health.ssd.endurance.error

A vSAN disk exceeds the estimated endurance threshold.

esx.problem.vsan.health.ssd.endurance.warning

A vSAN disk exceeds 90% of its estimated endurance threshold.