New disk not visible when increasing local datastore capacity in ESXi

Products

• VMware vSphere ESXi

Issue/Introduction

When attempting to increase the capacity of a local VMFS datastore after replacing or adding a new disk, the new device does not appear in the list of available extents within the vSphere Client. This occurs even after performing a storage rescan.

• A new or replacement disk is successfully detected by the ESXi host but cannot be selected to expand an existing local datastore.

• The datastore currently consists of multiple disks (e.g., 10 or 11 disks).

• Storage rescan at the host or cluster level does not resolve the visibility of the new disk for expansion.

• New VMFS local datastore can be created using the new disk.

Environment

• Product: VMware vSphere ESXi 8.0 & 9.0

• Hardware: Local storage disks with mixed sector formats.

Cause

The issue is caused by a mismatch in the Physical Blocksize and Format Type between the existing disks in the datastore and the new disk. ESXi requires all disks contributing to a single VMFS datastore to have matching sector formats (e.g., all 512e or all 512n).

Example:

When the existing datastore is created using disks with Format Type and 512e and the newly added drive has Format Type of 512n, it would not list the drive when trying to expand the datastore capacity.

The command 'esxcli  storage core device capacity  list' can be used to verify the Physical Blocksize and Format Type.

+---------+--------------------+-------------------+---------------------+-------------+-------------+
| Device  | Physical Blocksize | Logical Blocksize | Logical Block Count |    Size     | Format Type |
+---------+--------------------+-------------------+---------------------+-------------+-------------+
| naa.id  |               4096 |               512 |          7501476528 | 3662830 MiB | 512e        | -------------------> Existing extent of the datastore show 512e
| naa.id  |               4096 |               512 |          7501476528 | 3662830 MiB | 512e        |
| naa.id  |                512 |               512 |          7501476528 | 3662830 MiB | 512n        | -------------------> Newly added drive show 512n Format.
+---------+--------------------+-------------------+---------------------+-------------+-------------+

Resolution

To resolve this issue, the physical sector format of the new disk must match the existing disks in the datastore.

Fix the hardware issue:

Work with hardware vendor to replace the drive with the required format type.

Verify and Add drive:

Once the drive is replaced, validate the drive's specifications for Physical Blocksize and Format Type.

1. Log in to the ESXi host via SSH.

2. Run the following command to identify the format type of the devices: Command: vdq -q | grep -iE "Name|FormatType|Physical Blocksize"

3. If the new drive is matching the Blocksize and Format type, the datastore can be expanded using the drive. 

4. Follow the instructions in the resolution section of the KB Unable to grow or expand a VMFS volume or datastore to expand the datastore capacity.

Matching the drive 'Format Type' and 'Physical Blocksize' allows the drive to be listed during datastore expansion as it aligns with the existing disk specifications.