Knowledge Base

To increase the size of a Datastore on a local boot storage device, recreate the partition layout to accommodate the larger filesystem, and then grow the Datastore to fill the larger partition.

1. Use the boot device hardware's management tools to add additional disk capacity to the device. For more information, engage your hardware vendor.
   
   
2. Open a console to the ESX host. For more information, see Unable to connect to an ESX host using Secure Shell (SSH) (1003807).
   
   
3. Obtain the device identifier for the Datastore to be modified (eg: naa, mpx, eui, vml, etc). For more information, see Identifying disks when working with VMware ESX (1014953).
   
   vmkfstools -P "/vmfs/volumes/DatastoreName/"

   Example output:
   
   VMFS-3.33 file system spanning 1 partitions.
File system label (if any): DatastoreName
Mode: public
Capacity 145223581696 (138496 file blocks * 1048576), 43937431552 (41902 blocks) avail
UUID: 4a14d968-88bf7161-700f-00145ef48f76
Partitions spanned (on "lvm"):
    mpx.vmhba0:C0:T0:L0:5

   Note: To obtain this information for the Datastore containing the Service Console virtual disk (VMDK) on ESX, use the command: vmkfstools -P `esxcfg-init --cos-vmdk`
   
   
4. Record the amount of free disk space on the Datastore. For more information, see Investigating disk space on an ESX or ESXi host (1003564).
   
   
5. Equipped with the device identifier, identify the existing partitions on the device using the partedUtil command. For more information, see Using the partedUtil command line utility on ESX and ESXi (1036609).
   
   partedUtil get "/vmfs/devices/disks/mpx.vmhba0:C0:T0:L0"
   
   For example, a disk containing an ESX 4.x installation with 4 existing partitions:
   
17834 255 63 286515200     - Geometry of the disk. Disk size in sectors is 286515200.
1 63 2249099 131 128       - Primary #1, Type 131=0x83=Linux, Bootable, Sectors 63-2239099
2 2249100 2474009 252 0  - Primary #2, Type 252=0xFC=VMKcore, Sectors 2249100-2474009
3 2474010 286487144 5 0  - Primary #3, Type 5=Extended, Sectors 2474010-286487144
5 2474073 286487144 251 0  - Logical #5, Type 251=0xFB=VMFS, Sectors 2474010-286487144
| |       |         |   |
| |       |         |   \--- attribute
| |       |         \------- type
| |       \----------------- ending sector
| \------------------------- starting sector
\--------------------------- partition number
   
   
6. Identify the partitions which need to be resized, and the size of the space to be used. From the example in step 5, Logical Partition 5 is contained within Extended Partition 3, they are the last partitions on the disk, and there is empty free space between them and the end of the disk. For example:
   
   

   				Datastore
   				2474073	286487114
   				Logical Partition 5 Type 251 (VMFS)
   63	2249099	2240100	2474009	2474010	286487114	286487145	286515199
   Primary Partition 1		Primary Partition 2		Extended Partition 3 Type 5		Empty Space To Be Used

   
   
7. Identify the desired ending sector number for the target VMFS Datastore's partitions. To use all space out to the end of the disk, subtract 1 from the disk size in sectors as reported in step 5 to obtain the last usable sector.
   
   For example, Disk sector count 286515200 - 1 = 286515199 as the last usable sector.
   
   
8. Resize the partition(s) containing the target VMFS Datastore using the partedUtil command, specifying the existing starting sector of the partition and the desired ending sector:
   
   partedUtil resize "/vmfs/devices/disks/device" PartitionNumber NewStartingSector NewEndingSector
   
   For example, to resize the Extended and Logical partitions from the example in step 5:
   
   partedUtil resize "/vmfs/devices/disks/mpx.vmhba0:C0:T0:L0" 3 247010 286515199
partedUtil resize "/vmfs/devices/disks/mpx.vmhba0:C0:T0:L0" 5 247073 286515199
   
   
9. During step 8, the partedUtil command may report the warning:
   
   The kernel was unable to re-read the partion table on /dev/device (Device or resource busy).
   
   If you receive this warning, reboot the host before proceeding with the next step. For more information, see Rebooting an ESX Server host (1003530).
   
   
10. The partition tables have been adjusted, but the VMFS Datastore within the partitions is still the same size. There is now empty space within the partition in which the VMFS Datastore can be grown. For example:
    
    

    				Datastore	Empty Space
    				2474073	286515199
    				Logical Partition 5 Type 251 (VMFS), Now Larger
    63	2249099	2240100	2474009	2474010	286515199
    Primary Partition 1		Primary Partition 2		Extended Partition 3 Type 5, Now Larger

    
    
11. Grow the VMFS Datastore in to the new space using the vmkfstools --growfs command, specifying the partition containing the target VMFS Datastore twice.
    
    vmkfstools --growfs "/vmfs/devices/disks/device:partition" "/vmfs/devices/disks/device:partition"
    
    For example:
    
    vmkfstools --growfs "/vmfs/devices/disks/mpx.vmhba0:C0:T0:L0:5" "/vmfs/devices/disks/mpx.vmhba0:C0:T0:L0:5"
    
    
12. Validate that the size of the VMFS Datastore has increased. For more information, see Investigating disk space on an ESX or ESXi host (1003564).
    
    Note: Click the Refresh button in the vSphere Client to update the Datastore capacity and usage.