Freeing Disk from VMware Virtual Flash Read Cache (vFRC)

I was toying with vFRC in my lab and when I was done, I deleted the volume from the vSphere web client, but the local flash disk had retained its GPT partition format and was still claimed as a VMFS volume. I was unable to use that disk for other applications.

Try deleting using the web client:

 
Select the host then go to Manage tab then select Storage option and from there choose the Storage Devices entry. Select the disk, then click on the gear icon and choose Erase Partitions. Make sure you selected the right disk because this will wipe everything.


Via CLI: To delete the disk partition, first enable SSH on the host, then login and list all disks:
 ls -l /vmfs/devices/disks/

Sample output:
ls -l /vmfs/devices/disks/
total 495867432
-rw-------    1 root     root     8004304896 Feb 29 08:45 mpx.vmhba32:C0:T0:L0
-rw-------    1 root     root       4161536 Feb 29 08:45 mpx.vmhba32:C0:T0:L0:1
-rw-------    1 root     root     262127616 Feb 29 08:45 mpx.vmhba32:C0:T0:L0:5
-rw-------    1 root     root     262127616 Feb 29 08:45 mpx.vmhba32:C0:T0:L0:6
-rw-------    1 root     root     115326976 Feb 29 08:45 mpx.vmhba32:C0:T0:L0:7
-rw-------    1 root     root     299876352 Feb 29 08:45 mpx.vmhba32:C0:T0:L0:8
-rw-------    1 root     root     2684354560 Feb 29 08:45 mpx.vmhba32:C0:T0:L0:9
-rw-------    1 root     root     128035676160 Feb 29 08:45 t10.ATA_____ADATA_SP600_____________________________7F1820011415________
-rw-------    1 root     root     128033579008 Feb 29 08:45 t10.ATA_____ADATA_SP600_____________________________7F1820011415________:1
-rw-------    1 root     root     120034123776 Feb 29 08:45 t10.ATA_____KINGSTON_SV300S37A120G__________________50026B7255068D61____
-rw-------    1 root     root     120032591872 Feb 29 08:45 t10.ATA_____KINGSTON_SV300S37A120G__________________50026B7255068D61____:1
lrwxrwxrwx    1 root     root            20 Feb 29 08:45 vml.0000000000766d68626133323a303a30 -> mpx.vmhba32:C0:T0:L0
lrwxrwxrwx    1 root     root            22 Feb 29 08:45 vml.0000000000766d68626133323a303a30:1 -> mpx.vmhba32:C0:T0:L0:1
lrwxrwxrwx    1 root     root            22 Feb 29 08:45 vml.0000000000766d68626133323a303a30:5 -> mpx.vmhba32:C0:T0:L0:5
lrwxrwxrwx    1 root     root            22 Feb 29 08:45 vml.0000000000766d68626133323a303a30:6 -> mpx.vmhba32:C0:T0:L0:6
lrwxrwxrwx    1 root     root            22 Feb 29 08:45 vml.0000000000766d68626133323a303a30:7 -> mpx.vmhba32:C0:T0:L0:7
lrwxrwxrwx    1 root     root            22 Feb 29 08:45 vml.0000000000766d68626133323a303a30:8 -> mpx.vmhba32:C0:T0:L0:8
lrwxrwxrwx    1 root     root            22 Feb 29 08:45 vml.0000000000766d68626133323a303a30:9 -> mpx.vmhba32:C0:T0:L0:9
lrwxrwxrwx    1 root     root            72 Feb 29 08:45 vml.010000000035303032364237323535303638443631202020204b494e475354 -> t10.ATA_____KINGSTON_SV300S37A120G______________                                   ____50026B7255068D61____
lrwxrwxrwx    1 root     root            74 Feb 29 08:45 vml.010000000035303032364237323535303638443631202020204b494e475354:1 -> t10.ATA_____KINGSTON_SV300S37A120G____________                                   ______50026B7255068D61____:1
lrwxrwxrwx    1 root     root            72 Feb 29 08:45 vml.01000000003746313832303031313431352020202020202020414441544120 -> t10.ATA_____ADATA_SP600_________________________                                   ____7F1820011415________
lrwxrwxrwx    1 root     root            74 Feb 29 08:45 vml.01000000003746313832303031313431352020202020202020414441544120:1 -> t10.ATA_____ADATA_SP600_______________________                                   ______7F1820011415________:1


Find your disk there, and then list its partitions:
partedUtil getptbl /vmfs/devices/disks/

Sample output:
 partedUtil getptbl /vmfs/devices/disks/vml.010000000035303032364237323535303638443631202020204b494e475354
gpt
14593 255 63 234441648
1 2048 234440703 AA31E02A400F11DB9590000C2911D1B8 vmfs 0

You can see above that there's one partition labeled as "vmfs" which we need to get rid of. The leading number (in blue) is the partition number.

To delete the partition:
partedUtil delete /vmfs/devices/disks/

Sample output:
partedUtil delete /vmfs/devices/disks/vml.010000000035303032364237323535303638443631202020204b494e475354 1

Done. Look in vSphere web client and it should now report 0 primary partitions on that disk and you're free to use it for something else.

Check the partition table:
partedUtil getptbl /vmfs/devices/disks/vml.010000000035303032364237323535303638443631202020204b494e475354
gpt
14593 255 63 234441648