6.7

When you choose to change both the host and the datastore, the virtual machine state is moved to a new
host and the virtual disk is moved to another datastore. vMotion migration to another host and datastore
is possible in vSphere environments without shared storage.
After the virtual machine state is migrated to the alternate host, the virtual machine runs on the new host.
Migrations with vMotion are transparent to the running virtual machine.
When you choose to change both the compute resource and the storage, you can use vMotion to migrate
virtual machines across vCenter Server instances, data centers, and subnets.
Transferred State Information
The state information includes the current memory content and all the information that defines and
identifies the virtual machine. The memory content includes transaction data and the bits of the operating
system and applications that are in the memory. The defining and identification information stored in the
state includes all the data that maps to the virtual machine hardware elements. This information includes
BIOS, devices, CPU, MAC addresses for the Ethernet cards, chipset states, registers, and so forth.
Stages in vMotion
Migration with vMotion occurs in three stages:
1 When the migration with vMotion is requested, vCenter Server verifies that the existing virtual
machine is in a stable state with its current host.
2 The virtual machine state information (memory, registers, and network connections) is copied to the
target host.
3 The virtual machine resumes its activities on the new host.
If errors occur during migration, the virtual machine reverts to its original state and location.
Host Configuration for vMotion
Before using vMotion, you must configure your hosts correctly.
Ensure that you have correctly configured your hosts.
n
Each host must be correctly licensed for vMotion.
n
Each host must meet shared storage requirements for vMotion.
n
Each host must meet the networking requirements for vMotion.
Important The ESXi firewall in ESXi 6.0 and later does not allow per-network filtering of vMotion
traffic. Therefore, you must apply rules on your external firewall to ensure that no incoming
connections can be made to the vMotion socket on TCP port 8000.
vCenter Server and Host Management
VMware, Inc. 124