Some useful vmkfstools ‘hidden’ options

1. Display hosts which are actively using a volume

~ # vmkfstools –activehosts /vmfs/volumes/TEST-DATASTORE
Found 1 actively heartbeating hosts on volume ‘/vmfs/volumes/TEST-DATASTORE’
(1): MAC address 91:1a:b2:7a:14:d4

This option will show the management interface MAC address of any hosts which is actively using a datastore.

2.Display File Metadata, including Lock Information

~ # vmkfstools -D /vmfs/volumes/TEST-DATASTORE/TEST/TEST.vmdk
Lock [type 10c00001 offset 456325421v 44, hb offset 3268682
gen 6155, mode 0, owner 00000000-00000000-0000-000000000000 mtime 12783 nHld 0 n Ovf 0]
Addr <4, 558, 4>, gen 6, links 1, type reg, flags 0, uid 0, gid 0, mode 600
len 492, nb 0 tbz 0, cow 0, newSinceEpoch 0, zla 4305, bs 8192

3.Display VMFS File Block Details

~ # vmkfstools -P -v10 /vmfs/volumes/TEST-DATASTORE
VMFS-5.54 file system spanning 1 partitions.
File system label (if any): TEST-20
Mode: public
Capacity xxxxxxxxxxx (xxxxxx file blocks * xxxxxx), xxxxxxxxx(xxxxxxx blocks) avail
Volume Creation Time: Tue Feb 21 12:18:44 2012
Files (max/free): xxxxxx/xxxxx
Ptr Blocks (max/free): xxxxxx/xxxxxxx
Sub Blocks (max/free): xxxxxxx/xxxxxxx
Secondary Ptr Blocks (max/free): 256/256
File Blocks (overcommit/used/overcommit %): 0/115092/0
Ptr Blocks  (overcommit/used/overcommit %): 0/133/0
Sub Blocks  (overcommit/used/overcommit %): 0/6/0
UUID: xxxxxxxx-xxxxxxxx-xxxx-xxxxxxxxxxxx
Partitions spanned (on “lvm”):
naa.xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx:1
DISKLIB-LIB   : Getting VAAI support status for /vmfs/volumes/TEST-DATASTORE
Is Native Snapshot Capable: NO

4:VMDK Block Mappings

This command is very useful for displaying the mappings of VMFS file blocks to a VMDK. It can also be used to display the layout of a VMDK if you are concerned that a thin provisioned VMDK might be fragmented from a block allocation perspective.

~ # vmkfstools -t0 /vmfs/volumes/TEST-DATATSORE/TEST/TEST.vmdk