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Rahuldey
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Headroom calculation in an ESXi

Dear Community members,

I have to install an HBA in my ESXi host in the cluster. I have a 3 node cluster. As a part of sanity check ,I would like to determine if  other nodes in the cluster has enough memory and resources to accommodate the VM guests before I take the ESXi in maintenance mode and power it down. How can I determine this?

I want to avoid any situation during the maintenance window where the other ESXi nodes raise a flag during the vmotion that they are tight and cannot accommodate any VMs..

Would appreciate any suggestions in this matter

-Rahul

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vThinkBeyondVM
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Hi Friend,

    I believe, there is no tool to determine this automatically. You will have to manually see (in summary page ESXi host) that how much cpu/memory is being used by other hosts, note down + how much mem/cpu is being used by the host which you want to put into MM. This  will give you fair idea on whether all you VMs can be accommodated on all other hosts.

In addition to this. you will have to check HA/DRS (specially DRS threshold + DRS rules)/DPM/SDRS configuration so that these features will not be affected.


----------------------------------------------------------------
Thanks & Regards
Vikas, VCP70, MCTS on AD, SCJP6.0, VCF, vSphere with Tanzu specialist.
https://vThinkBeyondVM.com/about
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Disclaimer: Any views or opinions expressed here are strictly my own. I am solely responsible for all content published here. Content published here is not read, reviewed or approved in advance by VMware and does not necessarily represent or reflect the views or opinions of VMware.

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vThinkBeyondVM
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Hi Friend,

    I believe, there is no tool to determine this automatically. You will have to manually see (in summary page ESXi host) that how much cpu/memory is being used by other hosts, note down + how much mem/cpu is being used by the host which you want to put into MM. This  will give you fair idea on whether all you VMs can be accommodated on all other hosts.

In addition to this. you will have to check HA/DRS (specially DRS threshold + DRS rules)/DPM/SDRS configuration so that these features will not be affected.


----------------------------------------------------------------
Thanks & Regards
Vikas, VCP70, MCTS on AD, SCJP6.0, VCF, vSphere with Tanzu specialist.
https://vThinkBeyondVM.com/about
-----------------------------------------------------------------
Disclaimer: Any views or opinions expressed here are strictly my own. I am solely responsible for all content published here. Content published here is not read, reviewed or approved in advance by VMware and does not necessarily represent or reflect the views or opinions of VMware.

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Rahuldey
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Thanks a lot Vicky,

I have another query,I have VMs with RDM in a virtual MSCS cluster.. (the active node on 1st ESX and the passive node on second one).

Will there be any problem for them to get vmotioned to other nodes?

-Rahul

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vThinkBeyondVM
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On below guide on 5.5,

There is one statement under limitation : "Migration with vSphere vMotion® of clustered virtual machines".

Hence this is the limitation

http://pubs.vmware.com/vsphere-55/topic/com.vmware.ICbase/PDF/vsphere-esxi-vcenter-server-55-setup-m...

Also, Please follow comments on MSCS+RDM on below blog.

Migrating RDMs, and a question for RDM Users. | VMware vSphere Blog - VMware Blogs

It seems, its not supported.


----------------------------------------------------------------
Thanks & Regards
Vikas, VCP70, MCTS on AD, SCJP6.0, VCF, vSphere with Tanzu specialist.
https://vThinkBeyondVM.com/about
-----------------------------------------------------------------
Disclaimer: Any views or opinions expressed here are strictly my own. I am solely responsible for all content published here. Content published here is not read, reviewed or approved in advance by VMware and does not necessarily represent or reflect the views or opinions of VMware.

Rahuldey
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Thanks Vicky,

I meant just vMotion and not Storage vMotion.

Is vMotion also not supported on VMs w/RDMs?

-Rahul

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vThinkBeyondVM
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"Migration with vSphere vMotion® of clustered virtual machines".


Above statement under limitation (refer guide) is about vMotion (not storage vMotion),


blog link was about SVMOtion.


----------------------------------------------------------------
Thanks & Regards
Vikas, VCP70, MCTS on AD, SCJP6.0, VCF, vSphere with Tanzu specialist.
https://vThinkBeyondVM.com/about
-----------------------------------------------------------------
Disclaimer: Any views or opinions expressed here are strictly my own. I am solely responsible for all content published here. Content published here is not read, reviewed or approved in advance by VMware and does not necessarily represent or reflect the views or opinions of VMware.

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