vSphere 6 vMotion Enhancements

Starting with vSphere 6, VMware provided some new enhancements to the existing vMotion capabilities. Let us look at the history of vMotion over the last couple vSphere versions:

  • vSphere 5.0
    • Multi-NIC vMotion, which allows you to dedicate multiple NICs for vMotion
    • SDPS – Stun During Page Send has been introduced. SDPS ensures that vMotion will not fail due to memory copy convergence issues. Previously, vMotion might fail if the virtual machine modifies memory faster than it can be transferred. SDPS will slow down the virtual machine to avoid such a case
  • vSphere 5.1
    • vMotion without shared storage – vMotion can now migrate virtual machines to a different host and datastore simultaneously. Also, the storage device no longer needs to be shared between the source host and destination host

So, what are the new vMotion enhancements in vSphere 6? There are three major enhancements:

vMotion across vCenters

  • Simultaneously change compute, storage, networks and management
  • Leverage vMotion with unshared storage
  • Support local, metro and cross-continental distances

Screen Shot 2014-12-30 at 10.55.05 AM

Requirements for vMotion across vCenter Servers:

  • Supported only starting with vSphere 6
  • Same Single-Sign-On domain for destination vCenter Server instance using UI; different SSO domain possible if you use the API
  • 250 Mbps network bandwidth per vMotion operation


vMotion across vSwitches aka x-vSwitch vMotion)

  • x-vSwitch vMotion is fully transparent to the Guest.
  • Required L2 VM network connectivity
  • Transfers Virtual Distributed Switch port metadata
  • Works with a max of virtual switches

Screen Shot 2014-12-30 at 10.49.04 AM

Long-distance vMotion

  • Allows cross-continental vMotion with up to 100ms latency (Round-trip delay time)
  • Does¬†not require vVols
  • Use Cases:
    • Permanent migrations
    • Disaster avoidance
    • SRM/DA testing
    • Multi-site load balancing
  • vMotion network will cross L3 boundaries
  • NFC network, carrying cold traffic, will be configurable

Screen Shot 2014-12-30 at 11.01.00 AM


What’s required for Long-distance vMotion?

  • If you use vMotion across multiple vCenters, then vCenters must connect via L3
  • VM network:
    • L2 connection
    • Same VM IP address available at destination
  • vMotion network:
    • L3 connection
    • Secure (dedicated or encrypted)
    • 250 Mbps per vMotion operation
  • NFC network:
    • Routed L3 through Management Network or L2 connection
    • Networking L4-L7 services manually configured at destination

Long-distance vMotion supports Storage Replication Architectures

  • Active-active replicated storage appears as shared storage to the Vm
  • Migration over active-active replication is classic vMotion
  • VVOLs are required for geo distances

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