Last week there was a question that I received and the user was seeing an error message for the HA in the cluster.
- Ha Heartbeat Datastores For This Host Is 1
- Vsphere Ha Heartbeat Datastores Less Than Required
- Move Vsphere Ha Heartbeat Datastores
- Vsphere Ha Heartbeat Datastores Is 0
Recently, there was an internal request where the Engineer wanted to change the Datastore Heartbeat Configuration on the HA cluster and he wanted to update the configuration using PowerCLI. The task was to change the setting to Automatically select the datastores accessible from the hosts.
HA datastore heartbeating comes into play if a HA cannot reach other hosts on the network. The secondary datastore provides additional resilience, and if you don't want to create a second datatsore, you may consider to disable the warning (see HA error: 'The number of heartbeat datastores for host is 1, which is less than required: 2' (200473. For storage heartbeat, the minimum number of heartbeat datastores is two and the maximum is five. For vSphere HA datastore heartbeating to function correctly in any type of failure scenario, VMware recommends increasing the number of heartbeat datastores from two to four in a stretched cluster environment. The datastore is not used for vSphere HA heartbeat. The datastore is not part of a datastore cluster (managed by Storage DRS). The datastore is not configured as a diagnostic coredump partition. Storage I/O Control is disabled for the datastore. If the LUN is being used as an RDM, remove the RDM from the virtual machine. I believe this new Datastore Heartbeat feature is part of making HA more intelligent and able to make better decisions in the case of the Master HA Host being isolated or split off from other hosts.
The number of heartbeat datastores for host is 1 which is less than required 2
Before we move further, I just wanted to clarify a few things about the error message.
You would see this error message only in vCenter Server 5.x and above. The Datastore heartbeat is what the HA master node uses to differentiate between a failure of the host and an isolation of the host in the cluster.
There is also a Network heartbeat which is used by the HA to isolate the host in the cluster.
If both the network heartbeat and the datastore heartbeat is missing, then the host will be marked as dead and the VMs will be restarted on other hosts in the cluster.
Getting back to our original error message, you would ideally receive this message if there are less than two datastores used for heartbeat mechanism in the HA cluster.
By default, you need to have two datastores that can participate in the heartbeat mechanism for redundancy purposes.
There are two ways to get rid of this message:
Ha Heartbeat Datastores For This Host Is 1
- Add another datastore to the hosts that are part of the HA cluster.
- Change an advanced setting in HA to not show the error message even if there is only one datastore.
I highly recommend choosing the first option, the reason being that you would redundancy if there is an issue with one of your datastores.
Under some circumstances, you might want to use the second option, which is changing an advanced setting in the HA cluster.
If you are using a lab and do not sufficient resources to create another datastore or there is a specific requirement wherein you are requested to use only one datastore for the heartbeat mechanism.
The advanced setting that I am referring to is das.ignoreInsufficientHbDatastore. This set to false by default.
The below procedure will help you change the value to TRUE so that the error message will not be reported on the hosts.
Vsphere Ha Heartbeat Datastores Less Than Required
Below are the steps that can be used to change the setting:
- Log into vCenter Server.
- Right-click the cluster and click Edit Settings.
- Click vSphere HA > Advanced Options.
- Under Option, add an entry for das.ignoreInsufficientHbDatastore.
- Under Value, type true.
- Click OK to save the settings.
Move Vsphere Ha Heartbeat Datastores
Once you save the setting, right click on the ESXi host in the cluster that was reporting the message and click on Reconfigure for vSphere HA.
Once the HA is reconfigured, you should no longer see the warning message on the host.
Ha Heartbeat Datastores For This Host Is 1
- Add another datastore to the hosts that are part of the HA cluster.
- Change an advanced setting in HA to not show the error message even if there is only one datastore.
I highly recommend choosing the first option, the reason being that you would redundancy if there is an issue with one of your datastores.
Under some circumstances, you might want to use the second option, which is changing an advanced setting in the HA cluster.
If you are using a lab and do not sufficient resources to create another datastore or there is a specific requirement wherein you are requested to use only one datastore for the heartbeat mechanism.
The advanced setting that I am referring to is das.ignoreInsufficientHbDatastore. This set to false by default.
The below procedure will help you change the value to TRUE so that the error message will not be reported on the hosts.
Vsphere Ha Heartbeat Datastores Less Than Required
Below are the steps that can be used to change the setting:
- Log into vCenter Server.
- Right-click the cluster and click Edit Settings.
- Click vSphere HA > Advanced Options.
- Under Option, add an entry for das.ignoreInsufficientHbDatastore.
- Under Value, type true.
- Click OK to save the settings.
Move Vsphere Ha Heartbeat Datastores
Once you save the setting, right click on the ESXi host in the cluster that was reporting the message and click on Reconfigure for vSphere HA.
Once the HA is reconfigured, you should no longer see the warning message on the host.
Vsphere Ha Heartbeat Datastores Is 0
I hope this has been informative and thank you for reading!
