Part 1: Introduction to the vMotion process

hi welcome to this video I'm Neel Shah court and I work for VMware in a cloud platform business unit in this video I would like to talk to you about the vmotion process fee motion has been around a while now we actually introduced it in 2003 and over time we developed it to support new technologies looking at the motion and what it does in essence it's the ability to have a virtual machine running on the source ESXi host and we can now migrate the active state of that virtual machine to the destination host the important thing to understand here is that while being live migrated the application keeps on running there is no downtime involved we do have some requisite prerequisites for Vivi motion to to support free motion the most important thing is that we need a V motion enabled network between the ESXi ousts once this is set up we can now initiate a vMotion operation from the vCenter server UI we can also leverage tools like DRS our distributed resource scheduling feature DRS balances workloads across music's iOS within a cluster now DRS is able to automatically initiate V motion operations let's look at what a fee motion process actually is okay so now we know the basics of emotion let's dig a little bit deeper in what is going on when you hit that initiate when you initiate a fee motion process so first of all we have vCenter server right and in vCenter server what is happening is that we have started a long-running task now in that long-running task what it basically kicks off at first is a compatibility check that compatibility check is all about versioning so what for Jo machine needs to be migrated and what are the ESXi source and what does T is excited destination host what versions do they run and is it actually is the vm compatible to run on the destination host once that compatibility check is done we will now create a migration spec this migration speck has a lot of details on the VM itself so what are the what is the virtual machine hardware that is configured for that VM what is what are other VM options that is that are configured for that specific VM what about the V motion Network details from this between the source and destination is x ì óù ç all that information is bundled in this migration spec now this migration spec is passed on to the VP XD process this is the virtual provisioning ex-demon that is running inside the V virtual Center server VP XD will now connect to the ESXi hosts both the source and destination host and it will communicate to the VP X a which is the agent that communicates with the daemon running inside Virgil Center server and the VP XA is obviously then running inside the ESX Iost now VP XA will communicate with the host D process running inside the ESXi host now host D has all the information about the host itself about the hardware and more importantly from a vMotion perspective it owns the VM state so hos Dean knows what state the VM is running in O's D will then go ahead and talk to the vmx process not to be confused with the vmx configuration file of a virtual machine but the vmx process now vmx process handles all the i/o to devices that are not critical to performance for that VM vmx will talk to virtual machine monitor VMM now vmm process does handle all the i/o requests to all the devices that are critical for VM for virtual machine performance so this is about all the computer resources CPU memory etc vm m and vm x actually set the virtual machine to an intermediate state so we can now not change the vm configuration while being in a V motion process once this is set up these two will talk to the kernel module and this module is basically the code for vMotion once this is all set up we begin communication with the destination ESXi host where basically the same is happening so VP XA is talking to OSD and iOS D is talking to VM x vm m is not involved on the destination side and that is because the virtual machine still lives on the source host right so that is where the memory is active right now and virgil machine monitor like we said handles the i/o to the memory as well so vm x will call out the kernel module on the destination host and between the kernel modules on its source and destination host sockets will be opened on the vMotion network the vmotion and naval network I'm a-saying so once this is all set up we now have everything in place for the VM to be migrated from the source music sigh OS to the destination musics Iost in the next video we will talk about what is going on from a memory pre copy perspective thank you for watching you

Channel: VMware vSphere

Views: 22,839

Keywords: vMotion, vmware, vSphere, VMware, esxi, vsphere

Id: 0Q_MPVeuWgc

Length: 6min 54sec (414 seconds)

Published: Tue Nov 12 2019