ESXi Host Upgrade Precheck through SDDC Manager fails with "There are one or more exceptions that would prevent the host from entering maintenance mode"

Products

• VMware SDDC Manager
• VMware Cloud Foundation

Issue/Introduction

• Upgrade attempt for ESXi hosts from SDDC manager fails at precheck with error:

• On the lcm logs on SDDC Manager, the precheck fail is observed on one of the hosts with entries in /var/log/vmware/vcf/lcm/lcm.log

YYYY-MM-DDTHH:MM:SS ERROR [vcf_lcm,0000000000000000,0000,upgradeId=########-####-####-####-############,resourceType=ESX HOST,resourceId=########-####-####-####-############,bundleElementId=########-####-####-####-############ [c.v.e.s.l.c.v. vsphere. VsphereUtils, Upgrade-10] Error during enter MAINTENANCE check. Generic error : Currently connected device 'CD/DVD drive 1' uses backing ' [<datastore_name>] <filename>. iso', which is not accessible.
YYYY-MM-DDTHH:MM:SS ERROR [vcf_lcm, 0000000000000000,0000, upgradeId=########-####-####-####-############,resourceType=ESX
HOST,resourceId=########-####-####-####-############,bundleElementId=########-####-####-####-############] [c.v.e.s.l.p.i.e. EsxVumUpdateStageRunnerImpl, Upgrade-10] Dry run of Enter MAINTENANCE mode failed for Esx host with list of errors : [Currently connected device 'CD/DVD drive 1' uses backing ' [<datastore_name>] <filename>. iso', which is not accessible

• On the vCenter Server where the concerned ESXi host is connected, entries are observed in /var/log/vmware/vpxd/vpxd.log

YYYY-MM-DDTHH:MM:SS info vpxd [#####] [Originator@#### sub=vpxLro opID=########] [VpxLRO] -- BEGIN lro-1981683 -- host-## -- vim. HostSystem. queryWhatIfEnterMaintenance -- ########-####-####-####-############(########-####-####-####-############)
YYYY-MM-DDTHH:MM:SS info vpxd[#####] [Originator@#### sub=VmCheck opID=########] CompatCheck results: (vim.vm. check. Result) [(vim. vm. check. Result) {
vm = 'vim. VirtualMachine: ########-####-####-####-############:vm-<vmid>',
host = 'vim. HostSystem: ########-####-####-####-############:host-<hostid>',
error = (vmodl. MethodFault) [
(vim. fault. CannotAccessVmDevice) {
device = "CD/DVD drive 1",
backing = "[<datastore_name>] <filename>. iso",
connected = true,
msg = "",

• On the ESXi Host, entries pointing to vmx name for the virtual machine referencing the iso is observed in /var/run/log/hostd.log

YYYY-MM-DDTHH:MM:SS In (###) Hostd[#######]: [Originator@#### sub=Vmsvc. vm: /vmfs/volumes/vsan:################################/########-####-####-####-############/<vm_name>.vmx] CacheDatastores: fileBacking [ ] /vmfs/volumes/<datastore>/filename.iso has null datastore reference

Environment

• VCF 5.x
• VCF 9.x

Cause

DRS fails to put the ESXi host into maintenance mode, as the virtual machine cannot be migrated out of the host due to iso being mounted.

Resolution

Unmount the ISO from the concerned virtual machine by following the below steps to resolve the issue and then proceed with the Upgrade Precheck:

1. Navigate to the VM object in either from vCenter Server vSphere Client or ESXi Host Client
2. Right click on the VM > Edit Settings
3. Look for CD/DVD drive row
4. Uncheck the "Connected" box to disconnect
5. Click OK to save.

Additional Information

VMotion fails with the compatibility error: Currently connected device uses backing which is not accessible