ESXi and SD-Cards

[Bab]

I read this KB about SD card  https://kb.vmware.com/s/article/85685

and I know new esxi storage lay-out has changed and has added new part ESX-OS DATA . As I understood the main reason we have to immigrate from SD-Card to disk such as ssd disk , nvme disk , ...for  install esxi is for the size of OS-DATA partition is increasing and SD-CRAD size is not suitable for it and the other write has been increased in new version of ESXi in this partition (OS-DATA) that SD card cannot tolerate it correctly. 

but want to know Is that possible use SD-card with 32G and create a scratch partition on shared storage for ESX - OS data ?

migrate vmware tools such as this KB to another path instead of OS-DATA:

https://kb.vmware.com/s/article/83376

 migrate core dump to other path 

If we do above . Can install ESXi on SD-card with 32G space ?

[mbartle]

My only advice i can offer is this :

DO NOT upgrade to 7.0.2 (any flavor) if you use SD cards. I've had clusters running at 7.0.1 with 16GB cards, moving scratch and coredump to disk and also offloading VMware tools to RAM. Not one single issue

I patch to 7.0.2c and 24 hours later 1 SD card dies on one blade. 48 hours later a second, so I am rebuilding back to 7.0.1

Unless you replace SD cards with m2 or SSD you are asking for trouble . Trust me 

[Bab]

But I am really confuse :

1 - As I know the issue with SD-card has been solved in Esxi 7.0.2Uc so this issue will happen in the next major of ESXi (I think probably according to KB 85685   " Starting from the next major vSphere release, SD cards/USB media as a standalone boot device will not be supported. SD cards cannot be used to store the OSDATA partition, and an additional persistent device will be required."

I am using HPE 32GB microSD Raid1 USB BOOT Drive . 

1 - Is that your means I cannot install or update to ESXi 7.0.2Ud on HPE 32GB microSD Raid1 USB BOOT Drive ?

2- According to doc the main issue for SD-card is the size of new lay-out that has been added to new version of ESXi (ESX-OSDATA) and the other IO that cannot handle by SD-CARD . so one of the solution that has mentioned in the doc is :

" If a persistent local device is not available as a boot device, SD cards can be used for boot bank partitions However a separate persistent local device to store the OSDATA partition (32GB minimum, 128GB recommended) must be provided"

So I can install Esxi such as before on SD-card and create a scratch partition on my shared storage such as /vmfs/volumes/LUN1/ and forward ESX-OSDATA such as log , core dump , VMware Tools on that and work with it . Is that correct ?

 

[Srijithk]

7.0 u2 d is not a major release it's just a patch

major releases tend to be U1 , U2 , U3 etc (not 7.0 u 2 a/b/c/d)

VMware will change architecture only in 8. x similar to what it did with 7.x by bringing VMFS-L

I believe 7. x will not have issues with SD cards (7.0u2 c code having the fix will be taken further in all 7.x versions)although it will not be supported/recommended as per them and even I won't be recommending SD cards/usb anyways no matter whether they are supported or not especially when we are aware of how the I/O operations tend to happen in them, it would also be better to stop using them in the first place 

[Bab]

Is that possible use follow plan :

I have 6 SSD disks and one HPE raid controller . is that possible create raid1 for 2 ssd disk to install esxi and use 4 ssd disk in AFA ? Do I need a specific raid controller or I can do it ?

[lukaslang]

Using a supported HPE Controller in the VMware HCL should be no problem. Simply create a RAID 1 with 2 of the SSDs and another RAID 5 with the 4 remaining disks. ESXi will then see 2 separate logical disks.

[Bab]

Thanks . But I am talking about vSAN not local disks and raid type.

[lukaslang]

Well I am no vSAN expert, but from my understanding you should be good to go to create a RAID 1 with two SSDs (directly on the RAID controller) as boot device and let the other 4 SSDs unconfigured to show them to the OS and then use 1 of them as Cache Disk and the 3 others as capacity disks (as long as all of them are on the HCL for vSAN and have the performance/endurance ratings for the different tiers).

[Duncan Epping]

you are not allowed to share the diskcontroller for booting ESXi and vSAN disks.

[Bab]

Is that recommendation or will not allow to do that while running vSAN ?

[Duncan Epping]

that is a support requirement.

[lukaslang]

Sorry for the dumb question, but this article especially says that it is fine (non best practice) for vSAN 7.0?

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

 

edit: ok it says that you should not mix RAID and JBOD

[Bab]

Thanks but in this KB https://kb.vmware.com/s/article/2129050  mentioned 

• ESXi host installation is permitted on non-vSAN disks attached to same controller for vSAN 7.0 and higher. This is NOT supported for vSAN 6.x and lower.

According to that we can implement this scenario:  2 disks with raid 1 to install ESXi (non-vSAN) and 4 ssd disks with raid0 use for vSAN . Is that correct ?

[Duncan Epping]

Strange. I follow these guidelines:

https://www.vmware.com/resources/compatibility/vsan_profile.html?locale=en

[Bab]

Unfortunately, VMware documents about vSAN are confusing . in one document mentioned we cannot install esxi on SSD but in the other KB said we can install just forwards ESX-OSDATA on persistent disk . Another in one document said we cannot use one controller for both vSAN and non-vSAN (esxi installation) traffic but in the other mentioned we can install 

 

I am really confuse . which one is correct ?

Is Is that possible use one raid controller for both type of vSAN and non- vSAN traffic (esxi installation) ?

Will it provide good performance ?

[Bab]

Would you please help me about it . I am really confused I have just one raid controller with 2*600GB sas disks and 4ssd disks so I want create raid1 for 2 sas disks to install ESXi on that and create raid0 for all ssd disks to run vSAN according to follow article :  https://kb.vmware.com/s/article/2129050

is that possible ?

 ESXi host installation is permitted on non-vSAN disks attached to same controller for vSAN 7.0 and higher. This is NOT supported for vSAN 6.x and lower.