How to determine if a disk is shared between two VMs?

[hpoirier8]

Hi,

I would like to know if there is a way to determine if a disk is shared beween 2 VMs , and is there a way to be sure that it is shared ?

The Disk at the ESX level can be seen as follows: ESX1

[root@ESX1:/vmfs/volumes/5a76d0ff-29374c60-0da2-ecb1d7b559f0/VM1] vmkfstools -D ./sli-strsrv-01-prd-cit_7-flat.vmdk
Lock [type 10c00001 offset 74498048 v 181, hb offset 4001792
gen 3, mode 3, owner 00000000-00000000-0000-000000000000 mtime 141128311
num 1 gblnum 0 gblgen 0 gblbrk 0]
MW Owner[0] HB Offset 3215360 5cad723b-b0731e06-6b91-ecb1d7b4cb90  (MAC Address VNIC0 - ESX1)
Addr <4, 153, 16>, gen 50, links 1, type reg, flags 0, uid 0, gid 0, mode 600
len 53687091200, nb 51200 tbz 0, cow 0, newSinceEpoch 51200, zla 3, bs 1048576

[root@ESX1:/vmfs/volumes/5a76d0ff-29374c60-0da2-ecb1d7b559f0/VM2] vmkfstools -D ./sli-strsrv-02-prd-cit_7-flat.vmdk
Lock [type 10c00001 offset 148422656 v 175, hb offset 3260416
gen 3, mode 3, owner 00000000-00000000-0000-000000000000 mtime 95353452
num 1 gblnum 0 gblgen 0 gblbrk 0]
MW Owner[0] HB Offset 3268608 5c71dc0c-40c9a88b-707d-ecb1d7b5a2d0 (MAC Address VNIC0 - ESX2)
Addr <4, 333, 16>, gen 50, links 1, type reg, flags 0, uid 0, gid 0, mode 600
len 53687091200, nb 51200 tbz 0, cow 0, newSinceEpoch 51200, zla 3, bs 1048576

The Disk at the ESX level can be seen as follows: On ESX2
[root@ESX2:/vmfs/volumes/5a76d0ff-29374c60-0da2-ecb1d7b559f0/VM1] vmkfstools -D ./sli-strsrv-01-prd-cit_7-flat.vmdk
Lock [type 10c00001 offset 74498048 v 181, hb offset 4001792
gen 3, mode 3, owner 00000000-00000000-0000-000000000000 mtime 141128311
num 1 gblnum 0 gblgen 0 gblbrk 0]
MW Owner[0] HB Offset 3215360 5cad723b-b0731e06-6b91-ecb1d7b4cb90 (MAC Address VNIC0 - ESX1)
Addr <4, 153, 16>, gen 50, links 1, type reg, flags 0, uid 0, gid 0, mode 600
len 53687091200, nb 51200 tbz 0, cow 0, newSinceEpoch 51200, zla 3, bs 1048576

[root@ESX2:/vmfs/volumes/5a76d0ff-29374c60-0da2-ecb1d7b559f0/VM2] vmkfstools -D ./sli-strsrv-02-prd-cit_7-flat.vmdk
Lock [type 10c00001 offset 148422656 v 175, hb offset 3260416
gen 3, mode 3, owner 00000000-00000000-0000-000000000000 mtime 95353452
num 1 gblnum 0 gblgen 0 gblbrk 0]
MW Owner[0] HB Offset 3268608 5c71dc0c-40c9a88b-707d-ecb1d7b5a2d0 (MAC Address VNIC0 - ESX2)
Addr <4, 333, 16>, gen 50, links 1, type reg, flags 0, uid 0, gid 0, mode 600
len 53687091200, nb 51200 tbz 0, cow 0, newSinceEpoch 51200, zla 3, bs 1048576

I dont see any lock as the 2 VMs are configured within a RHN Cluster in Active / Passive Mode.

Any help would be greatly appreciated.

Thanks in advance

Regards

[fabio1975]

Ciao 

By shared you mean Multi-write Disk?

Using Red Hat Clustering Suite or SUSE Linux on a vSphere 6.x vSAN Datastore (2151774) (vmware.com)

[hpoirier8]

Hi, Thanks for your update.

The vSphere version is : 6.0 MU3.

When I check thru the vCenter, the disk (Virtual Disk) is not suppposed to be shared as in the VM Parameters interface, the "Shared" option  shows "Not Share", but the person who did the configuration told me he created "Shared" disks between the 2 VMs (belonging to a RedHat cluster configuration).
So what I am looking for, or would like to know , is an option, or a command at the ESX level, which certifies that the person who prepared the configuration, did a mistake, and reveals that the disk is not at all shared between the 2 VMs.

thanks for your support.

hubert

[fabio1975]

Ciao

it is possible that you are using RDM disks (RDM = Raw device mapping)
In vpshere 6.0 to make a cluster with shared disks it was necessary to use RDMs.
Here are two links with details:

Identify RAW device

https://kb.vmware.com/s/article/1004814

Cluster on VMware vSphere

https://kb.vmware.com/s/article/2147661

Doc on RDM device

https://docs.vmware.com/en/VMware-vSphere/6.0/com.vmware.vsphere.storage.doc/GUID-9E206B41-4B2D-48F0...