Unable to reconnect ESXi host to vCenter after ESXi upgrade - Conflicting VMFS datastores one is force-mounted, the other is not

Products

• VMware vCenter Server

Issue/Introduction

Symptoms:

• ESXi host disconnects from the  vCenter Server after upgrade.
• Attempting to reconnect the ESXi host to the vCenter Server fails with an error:

" Datastore 'Test1' conflicts with an existing datastore in the datacenter that has the same URL (ds:///vmfs/volumes/########-########-####-############/), but is backed by different physical storage."

 

Environment

VMware vSphere ESXi 8.x

 

Cause

This issue is caused when datastore is forcefully mounted on some hosts while on others it is mounted normally.

• In the vpxd.log file of the VC this error "Conflicting VMFS datastores one is force-mounted, the other is not"  is seen:

2026-02-10T12:43:20.454+05:30 info vpxd[06240] [Originator@6876 sub=vpxLro opID=mlg9g89c-946-auto-qb-h5:70000557-c4] [VpxLRO] -- BEGIN task-3816414 -- host-462521 -- vim.HostSystem.reconnect -- ########-########-####-############(########-########-####-############)
2026-02-10T12:43:20.495+05:30 error vpxd[06240] [Originator@6876 sub=HostAccess opID=mlg9g89c-946-auto-qb-h5:70000557-c4] Conflicting VMFS datastores (url ds:///vmfs/volumes/########-########-####-############/) - one is force-mounted, the other is not
2026-02-10T12:43:20.515+05:30 error vpxd[06240] [Originator@6876 sub=Default opID=mlg9g89c-946-auto-qb-h5:70000557-c4] [VpxLRO] -- ERROR task-3816414 -- ########-########-####-############(########-########-####-############) -- host-462521 -- vim.HostSystem.reconnect: :vim.fault.ConflictingDatastoreFound
--> Result:
--> (vim.fault.ConflictingDatastoreFound) {
-->    faultCause = (vmodl.MethodFault) null,
-->    faultMessage = <unset>,
-->    name = "Test1",
-->    url = "ds:///vmfs/volumes/########-########-####-############/"
-->    msg = ""

 

Resolution

To identify which datastores are forcefully mounted, please refer to the following article - Identify if a datastore is force mounted on an ESXi host

Workaround:

1. Unmount datastores that are currently marked with the force-mount flag.
2. Apply the required patch to the ESXi host.
3. During the update workflow, verify that the ESXi host transitions to a connected state without issues.
4. Re-mount the datastores unmounted in Step 1. --> These will now appear as snapshot volumes.
5. Validate that no datastores remain mounted with the force-mount flag.