At the place I work, we experienced continuous “The ramdisk ‘root’ is full” issues on our vSAN ESXi nodes.

The first thing we did was to raise a support call and have vmware check what is filling up the ramdisk.

Support suggested that we need to limit the size of vsantraces to 200MB, and pointed to the below KB Article

https://kb.vmware.com/kb/2150320

This puzzled me, as the vsantraces was not full.

I kept digging and I found out that the scratch partition on the hosts was not pointing scratch -> /tmp/scratch

but it was on / instead.