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Online migrations between vCenters with VxRAIL
Hello,
I've seen some conflicting articles, posts about what is and isn't supported when migrating VM's from an existing environment into a new VxRAIL environment (with embedded vcenter). It doesn't sound like adding any of the existing (foreign) nodes into the VxRAIL vcenter is supported. So what I'd like to do is create the VxRAIL cluster using the customer's existing external VC. This should allow for some smoother migrations that are online and if the customer's existing VC is also a VM, I would think you can just migrated that over to live on the VxRAIL at the end - is that supported or is there something that limits this from happening?
Thanks for all the advice!
-K
marquesj
28 Posts
1
March 9th, 2017 14:00
Even though "technically" you can take a customer deployed vCenter and run it on a VxRail, it is not recommended nor supported because VxRail Manager will be unaware of the fact that it is indeed running physically on the VxRail cluster itself. To VxRail Manager, the vCenter and PSC are special "service VM's" that have a higher priority and a specific purpose that VxRail Manager takes into account as it manages the power on and power off of these VM's when using the VxRail deployed vCenter. This is extremely important that VxRail Manager takes these VM's into account because they need to be considered when doing appliance maintenance tasks like appliance shutdown as an example.
If you use a customer supplied vCenter and then move it onto the VxRail cluster, VxRail Manager will treat it like any other VM and will not be able to verify its availability when doing system maintenance. This lack of control is why we don't support this deployment scenario. When you attach a VxRail cluster to an existing Customer Supplied vCenter, it's understood that the availability and maintenance of that vCenter is no longer the responsibility of VxRail Manager. And thus VxRail Manager does not account for it during appliance maintenance. If you move a customer supplied vCenter to run on a VxRail Cluster, you do so at your own risk.
lmoglie
2 Posts
0
March 7th, 2017 05:00
Hi,
hope this link helps you https://www.emc.com/collateral/guide/h15844-vxrail-4-0-vcenter-server-pg.pdf .
> So what I'd like to do is create the VxRAIL cluster using the customer's existing external VC.
Yes you can
> This should allow for some smoother migrations that are online and if the customer's existing VC is also a VM, I would think
> you can just migrated that over to live on the VxRAIL at the end - is that supported or is there something that limits this
> from happening?
So, if you have two clusters, managed by a single vCenter you can hot migrate VMs from your production environment to the new VxRail environment. You can migrate in the same time both computer resource and storage.
For limitations watch the link.
Best Regards
Lorenzo
echolaughmk
522 Posts
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March 7th, 2017 16:00
Thanks Lorenzo,
I have read that doc and came to the same conclusions as what you state above and it doesn't sound like there is any issues with doing what I want to do given the external VC would be a VM that would eventually be moved to the VSAN datastore. Appreciate the confirmation. Always trying to find a way to do it online since most of the TS kits and other docs all only talk about outages to cutover (usually due to EVC), but always looking for clever ways to migrate online. Stinks you can bring other hosts into the VxRAIL vcenter today.
Thanks!
echolaughmk
522 Posts
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March 9th, 2017 12:00
To add to this thread, I got some more conflicting information from EMC that this is, in fact, NOT Supported to have the external VC that manages VxRAIL reside eventually on VxRAIL Storage. I don't understand why and see this as a bi limitation for migration enablement, but maybe someone from DellEMC can chime in here on the why's (and potentially update the docs out there).
Anyways....wanted to share with the greater public to help others.
HTH
echolaughmk
522 Posts
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March 9th, 2017 15:00
Thanks Jason...great explanation and what I was looking for. Any plans to allow this in the future? One suggestion also might be to update the vxrail/vcenter white paper to call this out because I am seeing it asked a lot more lately from customers that want to keep their existing vcenter setup, but might be looking to move an entire environment.
Thanks again for the great feedback.
marquesj
28 Posts
0
March 10th, 2017 06:00
You're welcome.
To answer your last question, it is not on any short term or medium term roadmap to support what you are looking for. That may change long term, but it's not something being considered at this time. VxRail will have a VxRail deployed vCenter option with which it has its pros and cons from an ease of use but limitation in flexibility in the scale of management and it will have the Customer Supplied vCenter Server which has more flexibility but less tightly coupled integration with the VxRail Manager LCM and is not recommended to run on the appliance itself.
echolaughmk
522 Posts
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March 11th, 2017 05:00
Thanks for the additional info Jason!
-Keith