It took me 5 years since my original reply but I finally got around to inflating my thin disk and the SCSI errors have gone away!
My original reply isn't showing the screenshot any more (it says 'Content not viewable in your region' because I guess Imgur blocked access to UK users apparently) - so here it is again for posterity on a different image host:
[image: 153ec5c6-d945-4840-bf1a-ba8b9c14f203.png]
For what it's worth to the guys at Netgate, you should write in your documentation that if you're using pfSense on VMware then you should NOT use thin disk provisioning when setting up the VM (use eager-zeroed-thick instead)! There is currently no mention of this on https://docs.netgate.com/pfsense/en/latest/recipes/virtualize-esxi.html
Here's the process that I followed to fix it (from my own notes):
Preface
Since inflating a thin disk requires the VM to be off, and since switching off the router's VM kills routing to vCenter (even via VMware Remote Console) where the Inflate would usually be performed; this solution can be used instead
Prerequisites
Power off the VM
Delete all snapshots (consolidate)
Check the size of the the VM's -flat.vmdk file
You will need a minimum of this amount of space free, and preferably twice this amount of space free - so that you can do the optional backup step too - E.G. if the VMDK is 100GB, then you'll need at least 100GB free to inflate; plus another 100GB = 200GB free in total, if you do the optional backup step too!
Method
Read the Prerequisites first!
SSH to the ESXi host:
cd "/vmfs/volumes/<SOME_GUID_HERE>/RTR01/"
ls -lah RTR01*.vmdk*
cp RTR01.vmdk RTR01.vmdk.bak
Optionally backup the disk:
The cp command will backup the disk to a new file - you will need at least TWICE the amount of space free if you're doing this step!
cp RTR01-flat.vmdk RTR01-flat.vmdk.bak
Monitor progress at: ESXi host > Datastore browser > The volume > RTR01-flat.vmdk.bak > See the file size > Click Refresh on the dialog box's toolbar
Continue:
The vmkfstools -i command will inflate the disk to a new file - you will need a minimum of this amount of space free!
ls -lah RTR01*.vmdk*
vmkfstools -i RTR01.vmdk RTR01-thick.vmdk -d eagerzeroedthick
ls -lah RTR01*.vmdk*
mv RTR01.vmdk RTR01.vmdk.orig
mv RTR01-flat.vmdk RTR01-flat.vmdk.orig
mv RTR01-thick.vmdk RTR01.vmdk
mv RTR01-thick-flat.vmdk RTR01-flat.vmdk
ls -lah RTR01*.vmdk*
Edit the path to the -flat.vmdk by removing -thick using Vim:
vi RTR01.vmdk
Go down to the line, optionally press 'i' to enter Insert mode, delete -thick, then save with 'Esc' > ':wq'
Power on the VM
Confirm routing works properly to VMs
Clean up:
rm -f RTR01.vmdk.bak RTR01-flat.vmdk.bak RTR01.vmdk.orig RTR01-flat.vmdk.orig
ls -lah RTR01*.vmdk*
