vRealize Operations Manager generates an alert if a problem occurs with the components in the storage area network that the vSAN adapter is monitoring.

Table 1. vSAN Alert Definitions

Alert

Alert Level

Affected Object Type

Description

Performance Service on vSAN cluster might be off or experience issues

Critical

vSAN Adapter Instance

Triggered when the vSphere Virtual SAN Performance Service is off or experiences issues for one of the vSAN-enabled cluster compute resources.

Cleared by enabling Virtual SAN performance service in vSphere.

vSAN adapter instance failed to collect data from Virtual SAN Health Service. The health service might have issues.

Critical

vSAN Adapter Instance

Triggered when the vSAN adapter instance is unable to collect data from the vSphere Virtual SAN Health Service for one of the vSAN-enabled cluster compute resources.

Check Virtual SAN health service settings in vSphere.

vSAN Cluster disk space usage is approaching capacity

Warning

Cluster Compute Resource

Triggered when the disk usage in a vSAN cluster reaches 80% of capacity.

Cleared by removing virtual machines that are no longer in use or adding more disks to the cluster.

vSAN Cluster disk space capacity is less than 5%

Critical

Cluster Compute Resource

Triggered when the disk usage in a vSAN cluster reaches 95% of capacity.

Cleared by removing virtual machines that are no longer in use or adding more disks to the cluster.

vSAN Cluster flash read cache is approaching capacity

Warning

Cluster Compute Resource

Triggered when the Read Cache (RC) in the vSAN cluster reaches 80% of capacity.

Cleared by adding flash storage to the read cache.

vSAN Cluster flash read cache capacity is less than 5%

Critical

Cluster Compute Resource

Triggered when the Read Cache (RC) in the vSAN cluster reaches 95% of capacity.

Cleared by adding flash storage to the read cache.

vSAN Cluster virtual disk count is approaching capacity

Warning

Cluster Compute Resource

Triggered when the number of virtual disks per host in the vSAN cluster reaches 75% of capacity.

Cleared by adding most hosts to the cluster.

vSAN Cluster virtual disk count capacity is less than 5%

Critical

Cluster Compute Resource

Triggered when the number of virtual disks per host in the vSAN cluster reaches 95% of capacity.

Cleared by adding most hosts to the cluster.

vSAN Disk Group read cache hit rate is less than 90%

Warning

vSAN Disk Group

Triggered when the vSAN disk group read cache hit rate is less than 90%.

Cleared by adding more cache to accommodate the workload.

vSAN Disk Group read cache hit rate is less than 90% and write buffer free space is less than 10%

Warning

vSAN Disk Group

Triggered when the vSAN disk group read cache hit rate is less than 90% and the vSAN disk group write buffer free space is less than 10%.

Cleared by adding more flash capacity to the vSAN disk group.

vSAN Host has no VMkernel NIC configured

Immediate

Host System

Triggered when vSAN host has no VMkernel NIC configured.

Clears when the symptom disappears.

One or more physical disks on vSAN host is experiencing software state health issues

Critical

Host System

Triggered when one or more physical disks on vSAN host is experiencing software state health issues.

vSAN Performance Service is unable to communicate and retrieve statistics from host

Critical

Host System

Triggered when vSAN Performance Service is unable to communicate and retrieve statistics from host.

vSAN enabled hosts have inconsistent values for advanced configuration options

Critical

vSAN Cluster

Triggered when some advanced configuration settings have different values on different hosts in the vSAN cluster.

vSAN is disabled on the host

Critical

Host System

Triggered when vSAN is disabled on the host.

vSAN objects health will be impacted If this host stores any vSAN data (For example: virtual machine objects) on its local disks.

One or more vSAN enabled hosts are not in the same IP subnet

Critical

Host System

Triggered when one or more vSAN enabled hosts are not in the same IP subnet.

Host in a vSAN cluster does not have a VMkernel NIC configured for vSAN traffic

Critical

Host System

Triggered when host in a vSAN cluster does not have a VMkernel NIC configured for vSAN traffic.

Note:

Even if an ESXi host is part of the vSAN cluster, but is not contributing storage, it must still have a VMkernel NIC configured for vSAN traffic.

One or more hosts in the vSAN cluster have misconfigured multicast addresses

Critical

Host System

Triggered when one or more hosts in the vSAN cluster have misconfigured multicast addresses.

vSAN health service is not installed on the host

Critical

Host System

Triggered when vSAN health service is not installed on the host.

Host in a vSAN cluster has IP multicast connectivity issue

Critical

Host System

Triggered when host in a vSAN cluster has IP multicast connectivity issue. It means that multicast is most likely the root cause of a vSAN network partition.

Host in a vSAN cluster has connectivity issues and vCenter Server does not know its state

Critical

Host System

Triggered when host in a vSAN cluster has connectivity issues and vCenter Server does not know its state.

vSAN disk group has incorrect deduplication and compression configuration

Critical

Host System

Triggered when vSAN disk group has incorrect deduplication and compression configuration.

vSAN witness host has an invalid preferred fault domain

Critical

Host System

Triggered when vSAN witness host has an invalid preferred fault domain.

vSAN Cluster contains host whose ESXi version does not support vSAN Stretched Cluster

Critical

Host System

Triggered when vSAN Cluster contains host whose ESXi version does not support vSAN Stretched Cluster.

Host has invalid unicast agent and impacting the health of vSAN Stretched Cluster

Critical

Host System

Triggered when host has invalid unicast agent and impacting the health of vSAN Stretched Cluster.

An invalid unicast agent on the host can cause a communication malfunction with the witness host.

Storage I/O controller driver is not VMware certified

Critical

Host System

Triggered when stability and integrity of vSAN may be at risk as the storage I/O controller driver is not VMware certified.

Storage I/O controller is not compatible with the VMware Compatibility Guide

Critical

Host System

Triggered when vSAN environment may be at risk as the Storage I/O controller on the ESXi hosts that are participating in a vSAN cluster are not compatible with the VMware Compatibility Guide.

vSAN host and its disks have inconsistent deduplication and compression configuration with the cluster

Critical

Host System

Triggered when vSAN host and its disks have inconsistent deduplication and compression configuration with the cluster.

Unicast agent is not configured on the host and affecting operations of vSAN Stretched cluster

Critical

Host System

Triggered when unicast agent is not configured on the host and affecting operations of vSAN Stretched cluster.

The preferred fault domain is not set for the witness host in a vSAN Stretched cluster

Critical

Host System

Triggered when the preferred fault domain is not set for the witness host in a vSAN Stretched cluster and affecting the operations of vSAN Stretched cluster.

vSAN Stretched cluster contains a witness host without a valid disk group

Critical

Host System

Triggered when vSAN Stretched cluster contains a witness host without a valid disk group.

If the witness host does not have any disk claimed by vSAN then its fault domain is not available.

vSAN Stretched cluster has inconsistent configuration for Unicast agent

Critical

Host System

Triggered when vSAN Stretched cluster contains multiple unicast agents.

This means multiple unicast agents were set on non-witness hosts.

vSAN Stretched cluster does not contain a valid witness host

Critical

Host System

Triggered when vSAN Stretched cluster does not contain a valid witness host.

This affects the operations of vSAN Stretched cluster.

vSAN cluster has multiple network partitions

Critical

Host System

Triggered when vSAN cluster has multiple network partitions due to a network issue.

Witness host is a part of vSAN Stretched cluster

Critical

Host System

Triggered when witness host is a part of the vCenter cluster, which forms vSAN Stretched cluster.

Witness host resides in one of the data fault domains

Critical

Host System

Triggered when witness host resides in one of the data fault domains.

This affects the operations of vSAN Stretched cluster.

vSAN cluster has unexpected hosts

Critical

Host System

Triggered when vSAN cluster has unexpected hosts.

vSAN is unable to retrieve the physical disk information from host

Critical

Host System

Triggered when vSAN is unable to retrieve the physical disk information from host. vSAN Health Service may not be working properly on this host.

vCenter Server has lost connection to a host that is part of a vSAN cluster.

Critical

Host System

Triggered when host that is part of a vSAN cluster is in disconnected state or not responding and vCenter Server does not know its state.

vSAN has encountered an integrity issue with the metadata of an individual component on a physical disk

Critical

Host System

Triggered when vSAN has encountered an integrity issue with the metadata of an individual component on a physical disk.

vSAN is running low on the vital memory pool (slabs) needed for the operation of physical disks.

Critical

Host System

Triggered when vSAN is running low on the vital memory pool (slabs) needed for the operation of physical disks.

This can lead to a variety of performance issues such as virtual machine storage performance degradation, operation failures, or even ESXi hosts going unresponsive.

vSAN is running low on the vital memory pool (heaps) needed for the operation of physical disks.

Critical

Host System

Triggered when vSAN is running low on the vital memory pool (heaps) needed for the operation of physical disks.

This can lead to a variety of performance issues such as virtual machine storage performance degradation, operation failures, or even ESXi hosts going unresponsive.

vSAN is using a physical disk which has high congestion value

Critical

Host System

Triggered when vSAN is using a physical disk which has high congestion value.

This can lead to a variety of performance issues such as virtual machine storage performance degradation, operation failures, or even ESXi hosts going unresponsive.

Disk format version of one or more vSAN disks is out of date

Critical

Host System

Triggered when disk format version of one or more vSAN disks is out of date and is not compatible with other vSAN disks. This can lead to problems in creating or powering on VMs, performance degradation, and EMM failures.

vSAN Cluster has multiple Stats DB objects which are creating conflicts and affecting vSAN Performance Service

Critical

vSAN Cluster

Triggered when vSAN cluster has issues in electing stats master of vSAN Performance service.

This affects the functionality of vSAN Performance service.

vSAN cluster has issues in electing stats master of vSAN Performance service

Critical

vSAN Cluster

Triggered when vSAN cluster has issues in electing stats master of vSAN Performance service.

This affects the functionality of vSAN Performance service.

CLOMD process on the host has issues and impacting the functionality of vSAN cluster

Critical

Host System

Triggered when CLOMD process on the host has issues and impacting the functionality of vSAN cluster.

Number of vSAN components on a disk is reaching or has reached its limit

Critical

vSAN Cluster

Triggered when number of vSAN components on a disk is reaching or has reached its limit. This will cause failure in the deployment of new Virtual Machines and also impact rebuild operations.

vSAN HCL DB auto updater is not working properly

Critical

vSAN Cluster

Triggered when vSAN HCL DB auto updater is not working properly. This means that vSAN cannot download and update its HCL DB automatically.

vSAN has encountered an issue while reading the metadata of a physical disk

Critical

Host System

Triggered when vSAN has encountered an issue while reading the metadata of a physical disk and cannot use this disk.

Overall health of the physical disks in a vSAN Cluster is impacted

Critical

Host System

Triggered when overall health of the physical disks in a vSAN Cluster is impacted. See the health status of each physical disk individually on all the hosts.

vSAN performance service statistics database object is reporting issues.

Critical

Host System

Triggered when vSAN performance service statistics database object is reporting issues.

Overall health of vSAN objects is reporting issues

Critical

vSAN Cluster

Triggered when overall health of vSAN objects is reporting issues.

Number of vSAN components on a host is reaching or has reached its limit

Critical

Host System

Triggered when number of vSAN components on a host is reaching or has reached its limit.

This will cause failure in the deployment of new Virtual Machines and also impact rebuild operations.

Site latency between two fault domains and the witness host has exceeded the recommended threshold values in a vSAN Stretched cluster

Critical

vSAN Cluster

Site latency between two fault domains and the witness host has exceeded the recommended threshold values in a vSAN Stretched cluster.

Host ESXi version and the vSAN disk format version is incompatible with the other hosts and disks in a vSAN cluster

Critical

Host System

Host ESXi version and the vSAN disk format version is incompatible with the other hosts and disks in a vSAN cluster.

Statistics collection of vSAN performance service is not working correctly

Critical

vSAN Cluster

Triggered when statistics collection of vSAN performance service is not working correctly.

This means that statistics collection or writing statistics data to storage have failed for three consecutive intervals.

After one additional host failure, vSAN Cluster will not have enough resources to rebuild all objects

Critical

vSAN Cluster

Triggered when after one additional host failure, vSAN Cluster will not have enough resources to rebuild all objects.

vSAN cluster is reaching or has reached its limit for components, free disk space and read cache reservations

Critical

vSAN Cluster

Triggered when vSAN cluster is reaching or has reached its limit for components, free disk space and read cache reservations.

Disk load variance between some vSAN disks exceeded the threshold value

Critical

vSAN Cluster

Triggered when disk load variance between some vSAN disks exceeded the threshold value.

vSAN cannot perform the load balance properly.

Host is either running an outdated version of the vSAN Health Service VIB or It is not installed on the host

Critical

Host System

Triggered when host is either running an outdated version of the vSAN Health Service VIB or It is not installed on the host.

Storage I/O controller drivers is not supported with the current version of ESXi running on the host

Critical

Host System

Triggered when stability and integrity of vSAN may be at risk as the storage I/O controller driver is not supported with the current version of ESXi running on the host.

vSAN HCL DB is not up-to-date

Critical

vSAN Cluster

Triggered when vSAN HCL DB is not up-to-date.

vSAN cluster health checks are reporting issues

Critical

vSAN Cluster

Triggered when vSAN cluster health checks are reporting issues.

vSAN cluster Hardware Compatibility health checks are experiencing issues

Critical

vSAN Cluster

Triggered when vSAN cluster Hardware Compatibility health checks are experiencing issues.

vSAN cluster Limits health checks are experiencing issues

Critical

vSAN Cluster

Triggered when vSAN cluster Limits health checks are experiencing issues.

vSAN cluster network health checks are experiencing issues

Critical

vSAN Cluster

Triggered when vSAN cluster network health checks are experiencing issues.

Performance Service on vSAN cluster might be off or experiencing issues

Critical

vSAN Cluster

Triggered when performance service on vSAN cluster might be off or experiencing issues.

vROps will not be able to collect the data from vSAN cluster in this state.

vSAN Stretched cluster health checks are experiencing issues

Critical

vSAN Cluster

Triggered when vSAN Stretched cluster health checks are experiencing issues.

MTU check (ping with large packet size) has failed on vSAN host

Critical

Host System

Triggered when MTU check (ping with large packet size) has failed on vSAN environment due to some MTU misconfiguration in the vSAN network.

Basic (unicast) connectivity check (normal ping) has failed on vSAN host

Critical

Host System

Triggered when basic (unicast) connectivity check (normal ping) has failed on vSAN host due to network misconfiguration.

vSAN adapter instance failed to collect data from vSAN Health Service. The health Service might have issues.

Critical

Host System

Triggered when vSAN adapter instance failed to collect data from vSAN Health Service. The health Service might have issues.