For new installations of ESXi, during the autoconfiguration phase, a scratch partition is created on the installation disk if it is a high-endurance device such as a hard drive or SSD.

Note: Partitioning for hosts that are upgraded to ESXi 7.0 from earlier versions differs significantly from partitioning for new installations of ESXi. The size of bootbank partitions is different and autoconfiguration might not configure a coredump partition on the boot disk due to size limitations.

When ESXi boots, the system tries to find a suitable partition on a local disk to create a scratch partition.

The scratch partition is not required. It is used to store system logs, which you need when you create a support bundle. If the scratch partition is not present, system logs are stored in a ramdisk. In low-memory situations, you might want to create a scratch partition if one is not present.

The scratch partition is created during installation. Do not modify the partition.

If no scratch partition is created, you can configure one, but a scratch partition is not required. You can also override the default configuration. You can create the scratch partition on a remote NFS-mounted directory.