Executive Summary
In late August, Broadcom ended public downloads of their VMware Virtual Disk Development Kit (VDDK) from their website. The VDDK is a set of libraries and APIs that enables external software like backup, recovery, and migration tools to access and transfer data from VMware virtual disks managed through vSphere or hosted on ESXi infrastructure. Access to the VDDK has been restricted to select approved vendors. Broadcom has explicitly stated that the VDDK is not included with the VMware licensing. If your migration plans assume VDDK access, it’s worth revisiting them now.
Impact
The VDDK is used for direct access to Virtual Machine Disk (.vmdk) files, the file format used by VMware to store operating systems, applications, and data. The toolkit was used extensively by backup, disaster recovery, and migration vendors. Many third-party migration tools rely on the VDDK for their data transfer path. That means tools built around the dependency now face the access problem Broadcom just created.
Existing migration environments with VDDK already installed may continue operating, but projects that need to deploy, replace, or upgrade components could still be affected. Third party vendors cannot assume they may obtain or redistribute the VDDK; redistribution requires specific authorizations from Broadcom. Most major distributors of competing and replacement virtualization products depend on the VDDK to migrate customer workloads off vSphere onto the new platform.
Many vendors have already addressed this issue on their websites, directing customers to contact VMware for a resolution. Any VMware customers with existing VDDK deployments are advised to document their versions, permitted uses, support status, and recovery requirements.
Our Approach
Platform9’s vJailbreak migration utility initially relied on the VDDK and that remains one of three options for migrating VMs out of vSphere. While it’s a dependable tool, the VDDK doesn’t support the scale of migration for many of our customers. Based on real feedback from our customers using vJailbreak, we devised two additional methods of migrating VMs to take advantage of improved transfer speeds and the ability to multi-thread migrations.
Take back control with three migration options:
VDDK and NBD
The original migration option may still be viable for VMware customers who have already installed the VDDK. Using NBD (Network Block Device), the VDDK reads a VM’s virtual disk blocks from the ESXi host over the network and transfers them to the migration application. New migration projects will likely find this option blocked due to the removal of VDDK downloads.
Accelerated Copy
Platform9 developed Accelerated Copy in March 2026, based on direct customer feedback that VDDK-based transfers didn’t scale for their environment, months before Broadcom’s move made that same dependency a bigger problem for the rest of the market. Accelerated Copy provides a proprietary VDDK-independent transfer path designed to reduce the network bottlenecks associated with NBD-based migration. Accelerated Copy also supports parallel migrations and can scale through deployment of additional proxy appliances.
Storage Assisted
Storage-assisted migration uses the storage platform itself to copy or replicate a VM’s virtual disks to the destination environment. Because the data movement occurs at the storage layer, the migration does not depend on VDDK. Because the transfer is handled entirely by the storage array, VM and network latency do not impact throughput, storage-assisted migrations have been shown to run up to 10x faster than network-based transfer. vJailbreak currently supports storage assisted migrations with Pure, NetApp, and Hitachi Vantara storage arrays.
Broadcom’s removal of public VDDK access doesn’t have to prevent VMware migrations from proceeding. Organizations should verify whether their planned migration workflow requires a newly downloaded VDDK package and identify an alternative data path where necessary. With VDDK/NBD, storage-assisted migration, and Accelerated Copy, vJailbreak lets customers choose the method that fits their environment without making continued public access to VDDK a prerequisite.
Not sure which path fits your environment? Bring your current vSphere setup to a migration assessment with the Platform9 team. We’ll map your VMs, storage, and scale requirements to the right transfer path and scope a pilot in your own environment, before you commit to anything.
Author
