Moving Simplivity clusters between vCenter servers/federations

[AleksandarPeev]

Hi everybody,

Here is my set up.
I have two linked-mode vCenters that host 2 Simplivity clusters each.
As is standard, each pair of clusters are in their own Simplivity federation.
Each vCenter has had its own vCenter plugin installed and is managing its own federation.
This has its downsides that conncecting to either of the vCenters not necessarily shows its own federation as connecting to the vCenter plugin seems to be random. So at times you get the federation that you need sometimes .. the other one.

I would like to decommision one of the vCenters so that all of the clusters end up ibeing managed by a single vCenter and thus in a single federation.

I have tried moving the nodes of one cluster to the target vCenter and the OVCs connect correctly to the new vCenter, however they still believe that they are under the old federation.

My question to be precise is how do I repoint the OVCs to the target federation? I know that there is the dsv-federation-join command, but as documentation on the command is quite meager, I would like to know what risks does using that command entail, what does it actually do?

For extra points I would like to ask if you could referene any documents that actually describe the functionality of a Simplivity federation and the role that it plays in the Simplivity ecosystem.

I would highly appreciate your answers!

[support_s]

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[AleksandarPeev]

I just adore the bluntness of this reply!

Cmon, bots now take 32 minutes to process the discussion....

HPE please do not do this.

At least try to be helpful.

[W-Internal]

Unfortunatley you will need to re-deploy one of the clusters if you are looking to have a single Federation.  There is no other way around it.  Alternatively you can split the current set up and have 2 single vCenter Servers that you can move the nodes to.  That will keep the current setup in a non Linked vCenter mode.

[AleksandarPeev]

Hi,

I appreciate the straightforward NO.

I have a follow up question that I would be thrilled if you could answer.

Instead of  disconnecting one Vcenter I would rather do the following step to merge the clusters into a single federation.

The clusters that I have have 2 nodes each.
Are these steps in the following order reasonable?

1. Basically perform a decomissioning operation on one node of the cluster, thus having a single node cluster being left.
2. On the decomissioned node run the deploy process anew, basically reuse the current config, but join it to the target federation
3. Recreate Storage/Networking/Backup Policies
4. VMotion the VMs off of the source sigle node onto the node in the target federation
5. Once everything has been cleaned off, run the decomissioning process on the remaining node
6.  Run the deploy process anew on the cleaned off node and join it to the cluster of the first node , thus adding it to the target federation 

Would this procedure be supported by HPE as I would of course do it under supervision of an HPE engineer... I do have support at least

[W-Internal · Accepted solution]

That will be fine to do so but you will probbaly need to create a new Datacenter and Cluster.  If you are using the same vCenter Server you will also have to temporarily disconnect the remainning node during deployment so that the node you are re-deploying does not join the remaining node's Federation.  You can after Re-Deploying add the remaing node to vCenter and do your migrations.   

I hope this helps.

[AleksandarPeev]

Absolutely!

Thank you for the reply!

[Juliien]

Hello,

I am very interested in this article/question as I am about to perform this move.

Having 2 separate vcenters-Federations, I need to move a 2node (A & B) cluster from its own vcenter-fed to the other one.

-I understand the overall operation but I am wondering what you (@W-Internal) mean by "If you are using the same vCenter Server...".

-Also I am wondering : after reimaging the 1st node (A) and adding it to the target vcenter/federation, how do you vMotion the VMs from the remaining node (B)? 

     => do you just add (B) to the target vCenter (same cluster as A) and perform standard vMotion? if yes that would mean that the OVC-B that host (B) is carrying will connect to the source vcenter while host (B) will then be connected to the target vCenter?

     =>Or do you perform a cross-vCenter vMotion?

I hope I am being clear and you can answer these questions

J

[Sunitha_Mod]

Hello @Juliien,

Thank you for posting! Since you have posted in an old topic and there is no response yet, I would recommend you create a new topic using the create "New Discussion" button, so the experts can check and guide you further. 

[AleksandarPeev]

Hello Julian,

I am terribly sorry for my delayed answer!

I would recommend that you do a cross vCenter vmotion. I was restricted by the license (Essentials license does not support cross vCenter migrations, ....and yes I know i could have done it better by simply reverting to the trial license... hindsight 20/20).

What I did was  just add the node B to the target vCenter and to the target cluster (containing node A) and vmotioned the vms off of it to the node A.. yes this confuses the setup a bit as the OVC on node B is still reporting to the old vCenter, but even though the OVCs are in the same cluster they are not in the same federation, just consider them as two standalone Simplvity nodes in a federation of their own, but joined via the same netowrking set up for the purpose of transitioning through the federation move. Simplivity functions for the node B at that poing will not be available to you (available but not functioning) as the node B is foreign to the target federation. Once the VMs have vmotioned off .. you can just remove node B from the target vCenter and either rejoin it to the source vCenter, to perform any residual maintenance functions (like performing the actual removal of the residual federation, should you need to keep the old vCenter for other purposes, and not to leave trash) or just scrap the old vCenter (if not needed any more, that is what I did) and proceed with reimaging node B and join it to the target federation as the secondary node.

I hope i have answered your questions, but of course should you need any advice please do not hesitate to aks again.