CrashDodson
Contributor
Contributor

Fastest way to move data from a datastore

I am trying to find the fastest way to move data from a datastore to anywhere else.  I want to move entire VM's at a time.  My current test was the following:

An ESXI host version 5.5 connected to a SAN via 10G.  The san is all SSD drives.  I have a SSD Sas drive with server 2012R2 installed that I inserted into the ESXI host itself via a hotplug port.  I created a raw disk mapping to this device and used that mapping to boot the 2012R2 server on the SSD as a VM. 

On the 2012 VM I installed vsphere client, vsphere power CLI and veeam backup free edition. 

On ESXI I created a vswitch with a vmkernal and port group.  This vswitch has no phsyical NIC's assigned to it.  I IP'ed the vmkernal with 10.10.10.10 and placed my 2012VM in the port group and IP'ed the VM with 10.10.10.11.  Using this vswitch I can access ESXI from the VM using no ethernet connections.  In my mind it should be blazing fast. 

I used the 3 different methods of vsphere client, vsphere power cli, and veeam backup to copy a 100 GIG VMDK from the datastore (All SSD san via 10G) to my locally installed SSD drive/2012 R2 guest.  The copy took over an hour for all 3 methods.  I literally am getting usb 1 speeds on local attached disks. 

Can anyone explain this behavior and can anyone recommend a faster way to move virtualmachines from one datastore to another?  I need to quickly copy VMDK's to media/devices that can be taken to another location.  So storage vmotion and things like that will not work for me.  There is no reason that my above method should be slow. 

0 Kudos
4 Replies
CrashDodson
Contributor
Contributor

I can confirm that moving data between two RDM disks plugged into the same host is fast.  about 300mb/s.  but going from the RDM disk to a datastore is SLOW

0 Kudos
continuum
Immortal
Immortal

I sometimes do the following in recovery scenarios:
Assume the RDM is a link to /dev/disks/deviceXY
Assume you want to copy the RDM to the datastore /vmfs/volumes/datastore1/export/export.vmdk
Then try this:
dd if=/dev/disks/deviceXY of=//vmfs/volumes/datastore1/export/export-flat.vmdk bs=1M conv=notrunc
When that is done use cp to copy the vmx and the vmdk-descriptor.
Sometimes this procedures performs very well compared with other methods.


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

0 Kudos
CrashDodson
Contributor
Contributor

Thanks for your reply.

If I wanted to copy the VMDK on the datastore to the RDM would I just reverse this?  There is a windows NTFS file system on the RDM disk. 

0 Kudos
continuum
Immortal
Immortal

I never had a use case for that direction - so I cant say anything about how that will work.


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

0 Kudos