Provide storage for persistence of the logs from the hosts in the Virtual SAN cluster.
If you install ESXi on a USB or SD device and you allocate local storage to Virtual SAN, you might not have enough local storage or datastore space left for persistent logging.
To avoid potential loss of log information, configure the ESXi Dump Collector and vSphere Syslog Collector to redirect ESXi memory dumps and system logs to a network server. See the vSphere Installation and Setup documentation.