Where to install ESX?

[vmb01]

Hi everyone, I need to install a vSAN on a PowerEdge R740XD equipped with 1 SSD for caching and 2 HDD for capacity. Now I am considering to use a USB to boot ESX or to add a new HDD. My question is: if I use an entire HDD, can I share the same controller with the other capacity disk? Is there any best practices? HDD or USB?

Thank you

[TheBobkin]

Hello vmb01​

"Now I am considering to use a USB to boot ESX or to add a new HDD."

By USB, do you mean SD-card via USB-controller?

If so then this is (generally) a cost-effective option but shouldn't be also used for persistent logging as it will burn out relatively quickly.

"My question is: if I use an entire HDD, can I share the same controller with the other capacity disk?"

This depends - this is supported if it is in the same mode as the vSAN devices (e.g. passthrough) and the drive is not used for any VMs (e.g. only logging/dump etc.) then this is supported except on H730 where you have to remove every trace of VMFS after install is complete (and no logging in this case). However I would advise something inside the box e.g. SD-card/SATADOM as it can depend on the controller and there are some new provisions in 6.7 which may change what is supported.

Some useful articles relevant to your question:

https://kb.vmware.com/s/article/2129050

https://kb.vmware.com/s/article/2136374

https://blogs.vmware.com/virtualblocks/2016/03/18/virtual-san-design-considerations-for-booting-from...

Bob

[aleex42]

We are using a dual SD card (with RAID1) in our Dell R630 servers.

In the newer Dell Rx40er Servers this feature is called BOSS (Boot optimized storage solution) and consists of two M.2 SATA SSDs (RAID1, too).

http://i.dell.com/sites/doccontent/shared-content/data-sheets/en/Documents/Dell-PowerEdge-Boot-Optim...

Even better method than running your ESXi installation from USB or harddrives.

[MohamadAlhousse]

Hi vmb01​,

Please check the below link addressing the same concern:

VSAN Considerations with PERC R730 RAID Controllers - vExpert Consultancy

Regards,

[IRIX201110141]

Dell offer Dual SD Card (16-64GB in size) or BOSS  which mean 2x 120GB M.2 SSD as RAID 1. Both are supportet under vSphere and the DUAL SD is in use for years in our Hosts. We now have odered a couple of R740 with BOSS.

Regards,

Joerg

[mschubi]

Hello,

here my summary:

• Dual SD Modules in Mirror Mode works well on Dell servers but there are some limitations:
  • not supported on hosts with more than 512GB RAM
  • no persistant storage from the perspective of ESXi
  • you need persistant storage to store scratch log, vsan traces, core dumps and log files (no VSAN datastore!!!)
    
    
• lokal Disk for ESXi must be separated from VSAN HBA
  • you should not have any VMFS or ESXi partitions  on disks they are connected on the same bus like the VSAN disks
  • the prefered controller is the HBA330. There is no RAID functionality so you have to add a second RAID controller to run 2 additional disks in RAID Mode
  • in my point of view too expensive to boot ESXi
    
    
• DELL BOSS cards are the best way
  • PCI-E card with two M.2 drives starting on 120GB in RAID-1 Mode
  • persistant storage for ESXi
  • you can store all the Logs and Traces
  • independent of the used RAID controller

Concerning the costs is DUAL SD the cheapest, followed by BOSS...

best regards,

Mike

[aleex42]

mschubi​ dual SD also works for Dell servers with 768 GB for us

[mschubi]

Dual SD or other USB devices works well with more than 512GB but it is still not supported by VMware 🙂

Be carefull ....

best regards,

Mike

[aleex42]

Hm ok. We've ordered them in this configuration with VMware on it direct at Dell.

Until now no problems with VMware support cases on this machines ...