Tagging the Stateless Caching Disk using Autodeploy displays an inaccurate Is Local: value

Products

• VMware vCenter Server

Issue/Introduction

This article provides steps to properly tag disks as System Image Cache disks within a vCenter Server Auto Deploy configuration using host profiles.

Symptoms:

When your stateless caching configuration is configured to write to the first disk detected as local using a configuration similar to esx local, you experience these symptoms:

• The ESXi host incorrectly tags local disks as remote disks.
• Running the command esxcli storage core device list displays an inaccurate Is Local value similar to:
  
  naa.################################
  Display Name: HP Serial Attached SCSI Disk (naa.################################)
  Has Settable Display Name: true
  Size: 139979
  Device Type: Direct-Access
  Multipath Plugin: NMP
  Devfs Path: /vmfs/devices/disks/naa.################################
  Vendor: HP
  Model: LOGICAL VOLUME
  Revision: 6.40
  SCSI Level: 5
  Is Pseudo: false
  Status: degraded
  Is RDM Capable: true
  Is Local: false
  Is Removable: false
  Is SSD: false
  Is Offline: false
  Is Perennially Reserved: false
  Queue Full Sample Size: 0
  Queue Full Threshold: 0
  Thin Provisioning Status: unknown
  Attached Filters:
  VAAI Status: unknown
  Other UIDs: vml.######################################################
  Is Local SAS Device: false
  Is Boot USB Device: false
  
  
• Manually tagging disk(s) as local does not persist after a reboot and prevents the host from using the disk as a System Image Cache.

 

Resolution

To resolve this issue, when configuring a System Image Cache disk, use these arguments to define the disk for the cache:

• esx – The first disk detected containing a valid installation of ESXi
• local – The first local disk detected by ESXi after boot
• device model
• device vendor
• vmkernel device driver name

For more information, see the Configure a Host Profile to Use Stateless Caching section in the Set Up Stateless Hosts to Use Auto Deploy with Caching Guide.

 

For example, to configure a device as a System Image Cache using the device vendor tag:

1. Open a console to the ESXI host logging in as the root.
2. Run this command to list the detected storage devices:
   
   esxcli storage core device list
   
3. Locate the disk in which you want to configure as the System Image Cache and make note of the Vendor value.
   
   In this example, the Vendor value is Kingston:
   
   mpx.vmhba32:C0:T0:L0
   Display Name: Local USB Direct-Access (mpx.vmhba32:C0:T0:L0)
   Has Settable Display Name: false
   Size: 14883
   Device Type: Direct-Access
   Multipath Plugin: NMP
   Devfs Path: /vmfs/devices/disks/mpx.vmhba32:C0:T0:L0
   Vendor: Kingston
   
   
4. Log in to vCenter Server using the vSphere Client.
5. Navigate to Home > Management > Host Profiles.
6. Right-click the host profile and click Edit Profile.
7. Expand System Image Cache Configuration.
8. Under Arguments for the first disk field, add the vendor tag identified in Step 3.
   
   Note: You can use the Arguments for first disk field to specify a comma-separated list of disks to use, in the order of preference.
   
   
9. Click Finish to complete the host profile configuration.
10. Apply the host profile to update the configuration.

Additional Information

Use vSphere Auto Deploy for Stateless Caching and Stateful Installs