Of all the features available with vSphere - one of the greatest features I like is Storage vMotionwhich is described by VMware as follows:. All without downtime ok, one or two pings. Updated info vSphere 4. I was looking to understand more on how this exactly works - so I looked up Kit Colbert's Session from VMworld ancient, I know but still a great source of information.
That is all nice and fine - and now for a look under the covers - to see exactly what is happening. Opening a vSphere client session to the host itself, we will see a new VM that is created. Just before the the SvMotion is completed you will see that both machines co-exist for a short amount of time and both are powered on. And from an esxtop perspective. Here you can see that there is one VM with an ID of So here is the correct technical document for 4.
So what changed? CBT is now used to tracks the changes between the start of the process and the last stage just before the switch over. In this great session from Ali Mashtizadeh and Emre Celebi I learnt more about the process and how it now works in 4.
So how does this change performance-wise as compared to 3.
As you can see below the performance gain is substantial both in ESX CPU cycles used during the process and the time needed for the process. It is free and an hour well spent. The screenshots posted above showing the process are from a 4. And how does this work? Just before the the SvMotion is completed you will see that both machines co-exist for a short amount of time and both are powered on The switch is made and the old one is powered off and removed. Start the SvMotion and there are two VM's.Snapshots extremely simplify the Virtual Machine OS management and maintenance tasks by preserving the current state of the virtual machine.
So it allows you to revert to the state before the snapshot is taken. Before performing the OS patching or software upgrade, You need to take a backup such as OS Image level backup to restore the OS in case of any corruption is happened during the patching and also it is a time-consuming process. In VMware Virtual Machine, Snapshots simplifies the process to capture the Point-in-time copy of the virtual machine without the need of any third party backup software.
It also allows you to take multiple snapshots to preserve the multiple states of the virtual machine. It also simplifies the restore process. You just need to select the snapshot which is taken before patching to revert to the particular state of the virtual machine in case any issue happened during the patching. Name : Specify the name for the snapshot. Name of the snapshot should understandable easily from its name. Description: Provide a description for this snapshot.
You can even specify the Date and time to best identify its age. As of now, Just go with the snapshot without Virtual Machine memory.
Click Ok to create the snapshot. It is completed and Snapshot is created. It takes little longer time to create the memory snapshot as compared to snapshots with memory. Virtual Machine needs to be Powered on state to take the memory snapshot. If the virtual machine is in powered off state, Memory snapshot option will be grayed out.
This memory snapshot will allow you to restore the virtual machine to the same state as it was when a snapshot was taken. In Simple terms, it captures the live state of the virtual machine.
For Example, you are modifying a Microsoft word Document file and memory snapshot is taken at that time. After some time VM goes into Blue screen.
You want to restore the snapshot from the memory snapshot taken prior to the blue screen issue.
Deep dive with Enhanced VMotion
Snapshot with memory will revert the VM into powered on state along with the opened MS word file. Snapshot taken without memory option will not capture the live state of the virtual machine. Virtual Machine can be either in Powered on or Powered off state to take VM snapshot without memory option. It will be powered off. You need to manually power on the VM after reverting the snapshot.Though vMotion and Storage vMotion each serve a different purpose, they feature a large amount of overlapping technology.
Therefore these two vSphere functions fit well together in one chapter. Both technologies are proactive.
This means vMotion is used to migrate virtual machines between running ESX-hosts while Storage vMotion migrates the data between fully functional data stores on the virtual machines. Both vSphere features are no longer usable when the source or the destination is offline. VMware vMotion and Storage vMotion effectively protect against downtime because they can bridge maintenance windows on the hosts and datastores without any interruption of service.
However, contrary to popular speculation, they are not tools designed to increase high availability. Readers have certainly already heard of VMware vMotion, the live migration function within VMware vSphereso this introduction will be brief. With vSphere 5. This procedure was previously only possible as a cold migration process with offline VMs. However not every virtual machine is well suited for vMotion.
This point will be further discussed later in the chapter. Upon delving a bit deeper into vMotion one must admit that the functionality is both simple and ingenious. It ensures system reliability during a traditionally problematic time — maintenance of the host. Additionally it is easy to notice in vMotion how important it really is to separate the hardware from both the operating system and the applications.
The first step is to ensure that the source VM can be operated on the chosen destination server. Then a second VM process is started on the target system and the resources are reserved. Next a system memory checkpoint is created.
This means all changes to the source VM are written to an extra memory area. The contents of the system memory recorded at the checkpoint are transferred to the target VM. The last modifications to the main memory are transferred to the target VM in milliseconds.
The vMotion process is ended and a reverse ARP packet is sent to the physical switch important: Notify Switches must be activated in the properties of the virtual switch. Hard disk access is taken over by the target ESX.
The source VM is shut down. One additional comment about what the vMotion checkpoints record:. The guest system of course does not notice anything. Pre-Copy Iteration. As you can see in Table 1. Therefore an active vMotion process must always be allowed to run to completion even in the case that vCenter crashes.
Deep Dive Multi-nic vMotion
The vMotion user interface must be configured by an administrator and is installed on the VMkernel port. This means the vMotion data transfer must be enabled in the settings of the VMkernel port. Share on Pinterest Pin it. Share on Twitter Tweet.Most of the IT world has heard of vMotion. Allowing you to migrate off failing hardware or update hardware without interruption to the customers machine. Quite simply it is awesome. I can provide a basic overview a lot of the details are IP controlled by VMware.
Normal vMotion takes advantage of the following things:. The major portion of any virtual machine is data at rest on the shared storage. The only portion of a virtual machine not on the storage is the execution state and active memory.
When both copies are almost in sync VMware stuns the operating system for microseconds to transfer the workload to another compute node. Once transferred to the new compute node the virtual machine sends out a gratuitous arp to update the physical switches with the virtual machines new location.
Memory and execution state are transferred over the vMotion interface. Locking into shared storage became a problem for a lot of larger customers. VMware addressed this issue by providing storage vMotion. Storage vMotion allows a guest operating system to move between similar compute without shared storage between them or between different storage on the same compute. The only common requirement was networking and similar execution environment cpu instructions.
SvMotion has two types of data : active and cold. Active data are files that are read and writable. Cold data applies to any data that is not currently writable. Some examples of cold data are powered off virtual machines or parents files of the currently active snapshot only the active snapshot is considered active. In 6 the cold migration data is moved across the NFC protocol link designated as Provisioning traffic in vSphere 6.
So design consideration create a NFC designated vmkernel nic to avoid having management used. Storage vMotion can be offloaded to the array when the array supports VAAI and the movement is on the same array.
Multi-nic vMotion is the practice of using multiple nics to transfer vMotion data. Why would you need more nics? If multi-nic vMotion is configured correctly any vMotion job will be load balanced between all available links, thus increasing the bandwidth available to transfer data. A single machine vMotion can take advantage of the the multiple links.
This can really help the speed of vMotions. Multi-nic vMotion does have a cost. The cost is if you are moving a really large virtual machine you could saturate your links.In my latest blog posts we discussed the vSphere vMotion process in detail. Be sure to check this vMotion Deep Dive Series:.
This video will explain the basic concept of a workload live migration using vSphere vMotion. What happens when you initiate a vMotion? Watch the video to find out! In a previous video, we explained the vMotion process. This video will give detailed information on how vMotion keeps track of memory pages, and how memory is copied from the source to the destination ESXi host.
This video will share details on the vMotion stream architecture. It will show what can be done to tune vMotion bandwidth utilization for high bandwidth networks 25GbE and up.
In this video, we will explain how to troubleshoot vMotion. What logs files are used by the various processes. What to look for in those log files?
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I have configured it now and it works Hi CJ, I am planing to do the same. Did you configure it and does it Categories Virtualization 57 Storage 19 Networking 16 Random One of the biggest sticking points with ESX, in my opinion, has been the VMotion compatibility and processor classes. This point has produced some rather interesting support documents both from VMware and hardware vendors.
vSphere 5.1 vMotion Deep Dive
The basic concept is that it takes a group of heterogenous processors, determines the lowest common denominator between the group and then sets that as the baseline for the cluster. After that point, ESX will basically mask all newer processors down to the most compatible feature set. If an applications is running and utilizing a certain feature, then VMotions to a host without those processor features, the application will most likely blue screen, lock up or otherwise fail.
The solution which VMware has devised required intervention from its processor manufacturing partners, so the solution will only be available on certain newer processors which will allow their features to be masked. This is primarily because a running application may already be utilizing a feature which would be masked away within the cluster.
So its a small inconvenience, but easy solution to get this technology to market as quickly as possible for VMware. With a focus on data center technologies, he has built a career helping his customers and his employers deploy better IT solutions to solve their problems. Philip holds certifications in VMware and Microsoft technologies and he is a technical jack of all trades that is passionate about IT infrastructure and all things Apple.
He's a part-time blogger and author here at Techazine. View and opinions are my own and not reflective of my employer.
Is robotic process automation the perfect addition to Introduction to Cisco Intersight and what cloud system Investigating and setting syslog settings for ESXi with You may also like. June 9, December 13, VMware vCenter users are entitled to free December 11, June 7, May 24, We are doing a VM migration compute and storage.
We want to svmotion a powered on VM from source array to target array filer. What is the traffic flow for a powered on svmotion? Does it use the management interface to transfer the VM when going between source and target datastores? The reason we ask is that the Management Interface vlan 1 is connected to the firewall and we want to keep the traffic away from the firewall.
Please enter a title. You can not post a blank message. Please type your message and try again. Any feedback is much appreciated. I have the same question Show 0 Likes 0. This content has been marked as final. Show 2 replies. If it's a cross host or cross vCenter migration without shared storage it will. Hope that helps. Go to original post.