The health check service helps identify and troubleshoot configuration errors in vSphere distributed switches.

Health check helps identify the following common configuration errors.

  • Mismatched VLAN trunks between an ESXi host and the physical switches it's connected to.

  • Mismatched MTU settings between physical network adapters, distributed switches, and physical switch ports.

  • Mismatched virtual switch teaming policies for the physical switch port-channel settings.

Health check monitors VLAN, MTU, and teaming policies.


Checks whether the VLAN settings on the distributed switch match the trunk port configuration on the connected physical switch ports.


For each VLAN, health check determines whether the physical access switch port's MTU jumbo frame setting matches the distributed switch MTU setting.

Teaming policies

Health check determines whether the connected access ports of the physical switch that participate in an EtherChannel are paired with distributed ports whose teaming policy is IP hash.

Health check is limited to the access switch port to which the ESXi hosts' NICs connects.

Table 1. Distribute Switch Health Check Design Decisions

Design ID

Design Decision

Design Justification

Design Implication


Enable vSphere Distributed Switch Health Check on the virtual distributed switch.

vSphere Distributed Switch Health Check ensures all VLANS are trunked to all ESXi hosts attached to the vSphere Distributed Switch and ensures MTU sizes match the physical network.

You must have a minimum of two physical uplinks to use this feature.

A MAC address is assigned per VLAN per ESXi Host. With a large number of customer workload VLANs and a large number hosts, switch CAM tables may over ow.


For VLAN and MTU checks, at least two physical NICs for the distributed switch are required. For a teaming policy check, at least two physical NICs and two hosts are required when applying the policy.