Skip disk size requests for ISO files when retrieving VMs

When retrieving VMs, the platform can request the disk size for ISO disks on retrieved VMs. This request depends on the full availability and speed of the datastores, and may affect the overall speed and reliability of VM retrieval, especially if many of the VMs in your environment use ISO disks.

To configure the platform to try to obtain the size of ALL disk files including ISO disk files, on the Remote Services servers, set the isoSizeSkip property to false.

Notes

The configuration to skip ISO disk size requests has the following limitations:

• When capturing a VM that uses an ISO, the platform will report 0 size for the discovered ISO disk.

• When adding an ISO to an existing VM, the platform will discover the ISO disk and report 0 size. This includes Cloud-init ISOs, which usually have a small size.

• The platform will not include the capacity of discovered ISO disks when it checks limits and quotas, so users may obtain bonus storage space for these disks.

The platform manages pass through devices (without file backing) as size 0 disks but it does not record a datastore for them.

The platform updates datastore usage with a separate check, so the platform will correctly allocate datastore space.

Use cases

When you activate this configuration by setting isoSkipSize to true, the platform will not change the size of ISO disks already in VMs to 0.

When the configuration is activated:

• If you retrieve VMs, the platform will skip the request to obtain the disk size and set disk size to 0 for ISO disks

• If you deploy a VM with a template that includes an ISO disk (e.g. ubuntu-install.iso), the ISO disk in the VM will have the size from the VM template

• If you deploy a VM using cloud-init or add an ISO that is disk backed, the platform discovers the ISO disk, sets size=0, and reports the datastore

After you deactivate this configuration, the platform will update the size of existing ISO disks in VMs to their correct size.