ESXi sending frequent false SNMP traps for VM Heartbeat

Products

• VMware vSphere ESXi

Issue/Introduction

To stop the false SNMP traps.

Symptoms:

• Frequent SNMP traps on VMs and hosts
• There is output similar to

VMWARE-VMINFO-MIB:vmwVmHBLost and VMWARE-VMINFO-MIB:vmwVmHBDetected

Example: A "vmwVmHBLost" event has occurred, from GnSNMPDev device, named esxi1.. A
virtual machine has detected a loss in guest heartbeat. vmwVmID = 3
vmwVmConfigFilePath = /vmfs/volumes/########-########-f11/VM/VM.vmx
vmwVmDisplayName = VM vmwVmDisplayName.vmwVmIdx = 3

Cause

The SNMP trap provides a reverse poll, a way for a management system to generate an alarm when the ESXi system is not responding or is not reachable. An alarm should be generated indicating that the ESXi system is either slow or not responding when this particular trap is not received after twice the default sending period

Resolution

This issue is resolved in:

VMware vSphere ESXi 6.7 P03 (ESXi670-202008001)
VMware vSphere ESXi 7.0.1 Update 1.

However, it's advised to update to the latest ESXi 7.0 release. Please find the ESXi download packages by doing the following:

1. Login to the Broadcom Support Portal
2. Select "My Downloads"
3. Select "VMware vSphere"
4. Select the entitlement, i.e,
    "VMware vSphere - Enterprise Plus"
5. This window defaults to "Primary Downloads". Select the major version, i.e.
    "7.0" 
6. In the row titled "VMware vSphere Hypervisor (ESXi)" select "View Group"
7. In the upper right of the next window use the pull-down menu to select the minor version, i.e,
    "7.0U3n"
8. Select the cloud-download icon to download the ESXi ISO image or the ESXi offline bundle format file

Workaround:
To work around this issue:

1. Using the oid map from Determining the MIB module listing, name, and type of an SNMP OID
• Identity the traps to suppress.
• For example:

VMWARE-VMINFO-MIB vmwVmHBLost notification 1.3.6.1.4.1.6876.4.1.0.3
VMWARE-VMINFO-MIB vmwVmHBDetected notification 1.3.6.1.4.1.6876.4.1.0.4

2. Log in to the ESXi host through SSH.
3. Run the below command:

# esxcli system snmp set --notraps <MIB ID>
 

Note :where <MIB ID> is replaced with the ID of the MIB (e.g., 1.3.6.1.4.1.6876.4.1.0.3)

4. Run the command to list No Traps

# esxcli system snmp get

For more information also refer to VMware KB - SNMP Trap is repeated every 5 minutes

Additional Information

Impact/Risks:
None.