vmotion live migration

[Divyavm]

Hi,

I need to migrate a Virtual machine through live vmotion from one host to another, what will happpen to my network settings if both the host are in different network?

Will the ip address chang for the vm after vmotion to the target vm?

can anyone share videos on vmotion vm migrate when the virtual machine is powered on?

[AWo]

You need to have the same vSwitch (name) on both hosts. Otherwise vmotion won't let you migrate. They should be connected to the same IP subnet if you want to keep the network connection up and running. In any case, if the guest has a fixed IP setup it will keep that one. This is a guest setting.

I don't think that you see much in a vMotion video. You just klick on the migrate button, you decide what to migrate (guest, virtual disks or both, if you license allows you that) and where to move that. That's it.

AWo

[Divyavm]

what happens if the vm is not having static ip, and user is accessing the virtual machine which is getting migrated using vmotion. Will the ip address change for the vm?

Will there be any impact to the user or the vm will get slow or anything?

[Troy_Clavell]

...what happens if the vm is not having static ip, and user is accessing  the virtual machine which is getting migrated using vmotion. Will the ip  address change for the vm?

no.  All a vMotion is, at a high level, is a live migration of the active memory shares of the guest, from one ESX host to the other.  The IP inside the guest, whether DHCP or Static will not change.

Will there be any impact to the user or the vm will get slow or anything?

no.  Upon the final phase of the vMotion there may be a slight pause (equal to a single lost ping) while the VM completes it's migration.

[Divyavm]

is vmotion possible only with the shared datastore?

what will happen if the host are in different geographical locations?

how long does it take for vmotion?

[Troy_Clavell]

a requirement of vMotion is shared storage, yes.  A far a long distance vMotion, it can work, but you cannot vMotion across vCenter Servers. As for how long it takes, that depends.  Is your vMotion traffic on a private VLAN (which is should be).  Our vMotions usually on takes a few seconds.

[vGuy]

just for the info, there is also a very detailed & informative video on vMotion Architecture on youtube:

http://www.youtube.com/watch?v=uQR-gM0lEd8

[Divyavm]

Suppose if the Vswitch details of Virtual machine port groups are different in Source host and destination host, what will happen to the VM port groups, after Vmotion, will that be same as the host vswitch details or destination vswitch details?

Or this is condition valid?

[schepp]

The names of the virtual Machine Port Group must be identical on both hosts, otherwise vMotion won't start.

Regards

[UmeshAhuja]

Hi,

Kindly go through the below VMOTION REQUIREMENT:

HOST Base

Ensure that you have correctly configured your hosts in each of the following areas:

      ■ Each host must be correctly licensed for vMotion.

      ■ Each host must meet shared storage requirements for vMotion.

      ■ Each host must meet the networking requirements for vMotion.

STORAGE Base

     Configure hosts for vMotion with shared storage to ensure that virtual machines are accessible to both source and target hosts.

NETWORK Base

Migration with vMotion requires correctly configured network interfaces on source and target hosts.

vMotion requires a Gigabit Ethernet (GigE) network between all vMotion-enabled hosts. Each host enabled for vMotion must have a minimum of two Ethernet adapters, at least one of which must be a GigE adapter.

Recommended networking best practices are as follows:

     ■  Use one dedicated GigE adapter for vMotion.

     ■  If only two Ethernet adapters are available:

     ■  For best security, dedicate the GigE adapter to vMotion, and use VLANs to divide the virtual machine and management traffic on the other adapter.

     ■  For best availability, combine both adapters into a bond, and use VLANs to divide traffic into networks: one or more for virtual machine traffic and one for vMotion.

      Configure the virtual networks on vMotion-enabled hosts as follows:

     ■  On each host, configure a VMkernel port group for vMotion.

     ■  Ensure that virtual machines have access to the same subnets on source and destination hosts.

     ■  If you are using standard switches for networking, ensure that the network labels used for virtual machine port groups are consistent across hosts. During a migration with vMotion, vCenter Server assigns virtual machines to port groups based on matching network labels.

Note

You cannot migrate virtual machines that are attached to a virtual intranet with vMotion, even if the destination host has a virtual intranet configured with the same network label.

     ■  If you are using vSphere Distributed Switches for networking, ensure that source and destination hosts are members of all vSphere Distributed Switches that virtual machines use for networking.

     ■  Use of Jumbo Frames is recommended for best vMotion performance.

VIRTUAL MACHINE CONFIGURATION Base

A number of specific virtual machine configurations can prevent migration of a virtual machine with vMotion.

The following virtual machine configurations can prevent migration with vMotion:

     ■              You cannot use migration with vMotion to migrate virtual machines using raw disks for clustering purposes.

     ■              You cannot use migration with vMotion to migrate a virtual machine that uses a virtual device backed by a device that is not accessible on the destination host. (For example, you cannot migrate a virtual machine with a CD drive backed by the physical CD drive on the source host.) Disconnect these devices before migrating the virtual machine.

Virtual machines with USB passthrough devices can be migrated with vMotion as long as the devices are enabled for vMotion.

     ■              You cannot use migration with vMotion to migrate a virtual machine that uses a virtual device backed by a device on the client computer. Disconnect these devices before migrating the virtual machine.