How SVmotion Process works in background in 5.1

[MrVmware9423]

Dear team,

Just want to know if we perform SVMotion in vSphere5.1 what happens in the background., please find the my remarks in red, correct me if I m wrong.

copying VM files (What file it copy)

Preparing VM for Live Migration  (Here what it do )

Creating VM configuration (Creating same configuration file at destination datastore)

Migrating the active state of VM (Copying vmdk file)

Preparing VM files for Live migration  (at this step what it do in the background)

Cleaning up after migrating VMs (Over here it deletes source VMDK file or complete folder of that VM)

regards

Mr Vmware

[dhanarajramesh]

How Does VMware Storage VMotion Work? VMware Storage VMotion allows virtual machine storage disks to be relocated to different datastore locations with no downtime, while being completely transparent to the virtual machine or the end user. Before moving a virtual machines disk file, Storage VMotion moves the “home directory” of the virtual machine to the new location. The home directory contains meta data about the virtual machine (configuration, swap and log files). After relocating the home directory, Storage VMotion copies the contents of the entire virtual machine storage disk file to the destination storage host, leveraging “changed block tracking” to maintain data integrity during the migration process. Next, the software queries the changed block tracking module to determine what regions of the disk were written to during the first iteration, and then performs a second iteration of copy, where those regions that were changed during the first iteration copy (there can be several more iterations). Once the process is complete, the virtual machine is quickly suspended and resumed so that it can begin using the virtual machine home directory and disk file on the destination datastore location. Before VMware ESX allows the virtual machine to start running again, the final changed regions of the source disk are copied over to the destination and the source home and disks are removed. This approach guarantees complete transactional integrity and is fast enough to be unnoticeable to the end user refer to the vmware docs http://www.vmware.com/files/pdf/VMware-Storage-VMotion-DS-EN.pdf

[Sundararajan]

Below are the background process of Storage vmotion:

1. When SVmotion is initiated, it will first move the metadata file ( configuration,swap and log files) to the destination.

2.After locating metadata directory,then it will start migrating the VMDK files of Virtual machine to the destination.

3.In the mean while to leverage the data it will create a "Change Block Tracking" this will maintain the data integrity at the time of migration of VMDKs.

4. Once the process of copying VMDK is completed,it will suspend @ source and resumes in Destination.

5. Finally Before VMware ESX allows the virtual machine to start running again, the final changed regions of the source disk are copied over to the destination and the source home and disks are removed.

[engineer4kailas]

No CBT machanism after 5.0 ..

Refer the nice article byDuncan Epping

vSphere 5.0: Storage vMotion and the Mirror Driver - Yellow Bricks

[engineer4kailas]

1. When SVmotion is initiated, it will first copy the home directory with the metadata file ( configuration,swap and log files) to the destination.

2.After locating metadata directory,then it will start migrating the VMDK files of Virtual machine to the destination.

3.ongoing iops are copied to both source and destination by mirror driver

4. Once the process of copying VMDK is completed,it will suspend the vm on sourrce and start on destination

5.source home and disks are removed.