When using the vm-support data-collection utility on an ESXi host, either via the command-line or the vSphere client, it stores data in a temporary location under /var/tmp/. This is a symbolic link to /scratch/var/tmp/, which may have limited space available if the scratch location is on a ramdisk.
If many virtual machines are running on the ESXi system, vm-support needs more space than the directory can provide. As a result, vm-support fails, with an out of disk space message.
To resolve this issue, provide the vm-support command-line utility enough space to store temporary files during execution.
Provision a persistent scratch location on a Fat16 or VMFS partition accessible by the ESXi host. This scratch location will be used by the vm-support data-collection utility. For more information, see Creating a persistent scratch location for ESXi (1033696).
Execute the vm-support data-collection utility from the command-line of the ESXi host, specifying a temporary working directory.