If you’re on VMware vSphere 7 and you can’t figure out why your SD cards keep dying, or if you’re about to upgrade to vSphere 7 and you use SD cards as your boot storage, this is for you. Basically, VMware reconfigured how vSphere interacts with the storage partitions on the boot device and SD cards are just not going to be able to handle the write intensity anymore, so you’ll need to change that out for another form of storage. Other flash boot devices like SSDs or BOSS cards are NOT affected as much by this behavior.
The good news is that it shouldn’t be a very difficult task – you should be able to expand the storage in your existing servers.
But let’s get into the details…
Why is this happening?
VMware has a great article covering the ground on this, but here’s the high-level summary: VMware consolidated the boot partitions in vSphere 7, which adds lots of write intensity. SD cards aren’t designed to handle this type of workload, so it burns them out quickly. You may not notice this for practically four months as the SD burns itself out, but it is a safe bet that vSphere 7 will destroy your SD cards for booting.
Source: VMware
So what do I do?
Luckily, it shouldn’t be a huge feat to adjust how your boot storage is set up. You don’t need flash, so you can snap up some low-cost spinning disks from your preferred vendor and put them into your server. If your storage is all already allocated, or your servers don’t have the space for additional drives, we need to talk.