Booting off SD cards for ESXi host

[Chipperchoi]

Hello all,

I apologize in advance if this is a noob question but I am starting hear horror stories of booting your ESXi hosts off the SD cards on the host servers.

I do realize that the issue has become more apparent after the version 7 release but if I move the scratch\log location off the SD card to a SAN, is it still an issue? Am I really looking at inevitable failure of my hosts when the SD card wears out?

If so, is it possible to move the boot option off the SD cards to boot it off the SAN?

Many of the servers that we have already deployed have no drives in them. Just the SD card that was equipped from the manufacturer, HP and Dell.

Thanks in advance for any input. 

[IRIX201110141]

You should always adjust scratch partition and syslog setting when having a SD card as boot medium to a VMFS datastore (no vsan allowed).

We sold a couple of 100s of those servers and because of Dell comes with DUAL SD modules(its a Failsafe and not RAID1) since a long time we never see a lost of configuration. Yes we have to replace 2-3 SD card because of a failure and we also see Firmware related issue with the IDSDM. But it was a similar ratio compared to HDD replacement in a RAID1.

The ESXi loads into a RAM disk during start up and when you have redirected the logs than the wear level rate is quite low.

Right now the vendors doesnt offer the SD card together with vSphere 7anymore and i think it have to do with the OS_DATA partition VMware use now a days.

Regards,
Joerg

[Arthos]

Chipperchoi,

I can recommend this.

Solution
--------
1. If you want to move out of SD card. definitely you can boot off from SAN.
2. If you want to continue with SD card,
Note below points.
1. move scratch and log off from SD card.
2. SD card wearing out issues are more seen post 7.0 update 1. If you are pre 7.0 update 1 . you are safe.
3. Wait till the solution is permanently available in version 7.
4. refer this. https://kb.vmware.com/s/article/83376

-if it helps, consider marking it as helpful 

[Chipperchoi]

How do you proceed with moving the boot partition off the SD cards to a SAN or Harddrive?

Do I have to start over from scratch?

I have clients that are using single hosts for their remote offices with no option for vmotioning off the VMs while we work on that host. 

Is it something that can be moved without impacting operation?

[Arthos]

Without vMotioning the VMs , there will be a downtime for sure.

try this it can help, it works for me.

1. power off the VM gracefully.

2. Install ESXi onto Harddrive . if your vmdk is on HDD then make sure you don't format it during installation.

3. register the VM from vmx file and power on.

You can do this operation sequentially and try first on a test machine so that there will be less impact to the work.