Disk Format Converter (DFC) pre-check fails for a HCI Mesh vSAN environment with "Detected host(s) are running in mixed mode, please upgrade ESX servers to the same version."

Products

• VMware vSAN

Issue/Introduction

Symptoms:
vSAN HCI Mesh environment
Remote vSAN datastore
You see the below messages in the vsan health service logs
2021-01-29T06:43:01.801Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_CheckCluster opID=noOpId] 'vim.HostSystem:host-64': targetVersion 14
2021-01-29T06:43:01.801Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_CheckCluster opID=noOpId] 'vim.HostSystem:host-68': targetVersion 14
2021-01-29T06:43:01.802Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_CheckCluster opID=noOpId] 'vim.HostSystem:host-72': targetVersion 14
2021-01-29T06:43:01.803Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_CheckCluster opID=noOpId] 'vim.HostSystem:host-76': targetVersion 14
2021-01-29T06:43:01.804Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_CheckCluster opID=noOpId] 'vim.HostSystem:host-80': targetVersion 14

2021-01-29T06:43:01.977Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_ComputeTargetVersionForCluster opID=noOpId] 'vim.HostSystem:host-104': targetVersion 14
2021-01-29T06:43:01.978Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_ComputeTargetVersionForCluster opID=noOpId] 'vim.HostSystem:host-117': targetVersion 14
2021-01-29T06:43:01.978Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_ComputeTargetVersionForCluster opID=noOpId] 'vim.HostSystem:host-121': targetVersion 14
2021-01-29T06:43:01.979Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_ComputeTargetVersionForCluster opID=noOpId] 'vim.HostSystem:host-129': targetVersion 13
2021-01-29T06:43:01.980Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_ComputeTargetVersionForCluster opID=noOpId] 'vim.HostSystem:host-133': targetVersion 13
2021-01-29T06:43:01.980Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_ComputeTargetVersionForCluster opID=noOpId] 'vim.HostSystem:host-137': targetVersion 13

2021-01-29T06:43:02.118Z INFO vsan-mgmt[64234] [VsanClusterConfigHelper::GetRemoteVersionsSupported opID=noOpId] Supported version list for client cluster version 14: [13, 14]

2021-01-29T06:43:04.569Z INFO vsan-mgmt[64234] [VsanVcDiskFormatConverterImpl::_RunPreCheck opID=noOpId] Finished precheck on 'vim.ClusterComputeResource:domain-c164': (vim.cluster.VsanDiskFormatConversionCheckResult) {
issues = (vim.VsanUpgradeSystem.PreflightCheckIssue) [
(vim.vsan.upgradesystem.MixedEsxVersionIssue) {
msg = 'Detected host(s) are running in mixed mode, please upgrade ESX servers to the same version.'
}
],
isSupported = false,
isDataMovementRequired = false
}

Note: The preceding log excerpts are only examples. Date, time, and environmental variables may vary depending on your environment.

Environment

VMware vSAN 7.0.x

Cause

The client & server clusters participating in the HCI Mesh are on different ESXi versions resulting in the DFC pre-check failing with "Detected host(s) are running in mixed mode, please upgrade ESX servers to the same version."

HCI Mesh checks the server cluster's compatibility with the client cluster as part of the DFC pre-check.

Resolution

Ensure all vSAN clusters participating in the HCI Mesh are on the same ESXi version.