Guest-Side Migration Bridge for VMware
When VDDK disappears from a VMware migration plan, generate open images from inside the VM and automatically start shadow replicas in the target environment for validation.
After Broadcom stopped offering VDDK downloads, teams preparing to leave VMware can suddenly lose their host-side export path. An administrator registers a group of VMs to migrate, the target environment, and acceptable downtime in a migration console, then runs a shadow migration on one noncritical machine. The product clearly shows which credentials are missing for each machine, which guest OS permissions are available, and which application checks must be completed before migration.
A lightweight agent runs inside the VM. It freezes application writes, captures disk contents and boot configuration from the guest OS, and produces an open image. It translates network adapters, disk mounts, and boot parameters into configurations recognized by KVM, Proxmox, or a specified cloud environment. Services with consistency requirements, such as databases, must first use team-provided write-pause scripts; without a script, the VM remains in the pending queue.
Once the image reaches the target environment, the product automatically starts an isolated replica, saves the boot screen, and probes critical ports, service processes, and sampled data. Migration leads receive an item-by-item comparison report showing which services started, which configurations still need manual changes, and whether data checks match between the original and replica. The first usable version focuses on Linux VMs moving to KVM and Proxmox, so teams can validate small batches before scheduling a production cutover.
Why now
Starting August 25, multiple VDDK download paths were documented as unavailable; reporting on September 7 brought the change to the attention of more migration teams. S1 As of September 8 at 00:33 UTC, the related Hacker News item ranked ninth with 67 points and 28 comments, a point at which administrators were more likely to discover that their planned agentless migration workflow could no longer proceed. S2
Target user
Platform teams preparing to move a group of Linux workloads off VMware. When a host-side download or interface suddenly becomes unavailable, they must reassess the migration path. What they need is not another format-conversion guide, but a way to identify which machines have guest access, can produce consistent images, and can be started and validated in the target environment before cutover.
Minimal entry point
The first release is limited to Linux VMs using LVM, ext4, or XFS. The agent checks for root access, volume layout, free space, and boot mode. Application scripts establish a stable read point through write pauses, `fsfreeze`, and LVM snapshots; exports are blocked when requirements are not met. Disks stream as sparse blocks and land as raw or qcow2 images. The destination side integrates separately with libvirt and the Proxmox REST API. S4 After boot, it collects console output, port status, systemd services, and user-specified validation commands. The first release does not cover Windows, vTPM, or automated consistency across databases.
Punching above its weight
Find the first users among people seeking migration help in Proxmox, KVM, and private-cloud communities. Release a free read-only assessor that reports volume layout, boot mode, and missing requirements so administrators can determine whether a VM is migratable. Publish anonymized migration-report templates showing boot, port, and data-check results. Offer independent virtualization consultants batch workspaces they can bring directly into client projects.
Competitors & gaps
- Azure Migrate agent-based migrationGoogle
- Azure Migrate already offers agent-based VMware migration. It can continuously replicate disks and supports test migrations and production cutovers. When VDDK cannot be downloaded, Microsoft explicitly recommends switching to agent-based migration. S3 Its destination, however, is Azure, and migrated workloads remain constrained by Azure’s resource model. Teams moving to on-premises KVM or Proxmox still need image conversion, boot repair, and validation orchestration. It also requires a replication appliance, an Azure project, and cloud permissions. The opening is destination-neutral, guest-based collection that combines open-image creation, configuration conversion, and item-by-item validation in one workflow.
- Proxmox VE ESXi ImporterGoogle
- Proxmox VE includes an ESXi importer that can map most VM configurations and supports import methods intended to reduce downtime. S4 Its official workflow still requires access to ESXi or vCenter and recommends learning the process with test VMs first. Encrypted disks, vTPM, vSAN, and VMs with many snapshots have further limitations. S4 It works well when Proxmox is the confirmed destination and the team still has host-side access. If the organization cannot obtain host interfaces or is comparing several KVM destinations, the existing importer cannot handle guest-side collection. The gap is to export a neutral image from inside the VM, use the Proxmox API to create an isolated replica, and produce a consistent cross-platform validation report.
How it makes money
Charge per migration batch. The base plan includes a set number of Linux VMs, image staging, and shadow validation; additional VMs are billed per machine. An enterprise tier adds private deployment, audit logs, and retained migration reports.
The case against
Guest-side exports are constrained first by disk layout. Machines without space for LVM snapshots are difficult to image consistently while writes continue. Database write-pause scripts must also be maintained by application owners, and coordination costs rise with the number of services. Full-disk transfers consume production network capacity and lengthen shadow migrations. Boot repair can run into UEFI, VirtIO, network-interface naming, and encrypted volumes. A misconfigured isolated network could let replicas reach production dependencies or create address conflicts. A live port is not proof that the application is correct, and flawed validation would erode trust before the production cutover.