If Hosts are running their OS via SD-Cards/USB and vSAN is the only cluster storage (No other shared storage):
Are there solutions to still follow best practice for vSphere Cluster in above situation?
(Not looking for workarounds like setting up some VM with NFS Service to provide additional shared storage etc...)
@andvm vSAN use the vSAN network for HA heartbeat so no concern not having other datastores from that perspective.
Storing logs on vsanDatastore is not just not advised, it is unsupported, e.g. please don't do that.
What @IRIX201110141 suggested e.g. use a durable device for boot and also placing logging here is advised - SD card device for ESXi boot/install is not advised in modern versions https://kb.vmware.com/s/article/85685
@IRIX201110141 - Boss card is installed but think it came pre-configured as one virtual disk using all space (Raid1) and this is where ESXi is installed.
So looks like ESXi would need to be wiped and existing virtual disk removed to create two instead (and ESXi re-installed)
@TheBobkin - thanks for reminding me about the that vSphere HA uses the vSAN Network when vSAN is available.
Still however would have thought that heartbeat datastores are needed so that vSphere HA can confirm if Host has totally failed or just network partitioned. Probably I need to re-visit how vSAN reacts in case of vSAN network partitions or single Host losing both vSAN uplinks.
and now it depends..
@IRIX201110141 - Its BOSS-S1 so possible to delete and create 2x virtual disks as per your comment.
But in any case this will require the deletion of existing ESXi which is not ideal, so something that should be done first thing prior ESXi install.
Actually these are vSAN Ready Nodes so came with ESXi pre-installed now that I remember.
I wonder why these do not come pre-partitioned into 2x virtual disks knowing the vSAN requires a VMFS datastore?
Bottom line, adding a VMFS datastore via the BOSS Card might be possible but not straightforward in this case.
Please don't mid me asking. I'm a bit confused.
You said "If Hosts are running their OS via SD-Cards/USB ...".
Is ESXi really installed on SD cards rather than on the BOSS device?
apologies my bad as got another set of Servers which do have ESXi installed on SD.
Ultimately I think I got the answer which is that a vSAN Cluster will always need VMFS datastore (shared or per Host to function/follow best practice)