Migrating VMware VMs to zCompute

VMware VMs are migrated to zCompute by converting the boot disk using virt-v2v and migrating the other disks intact, as block devices.

There are two methods to migrate VMware VMs to zCompute:

  1. Migrate VMWare VMs from NFS share


    Recommended migration method

    The recommended migration option includes an NFS volume that is accessible to both the source virtualization platform (e.g. as a datastore for Vmware ESXi hosts) and to the importer VM over a direct subnet to which it’s attached.

    • High bandwidth / low latency connected source:


    • Limited bandwidth / high latency connected source:


  2. Migrate VMs using the VMware API

    Other, slower options involve copying the source VM’s virtual disks to the zCompute cloud from the virtualization platform’s management interface (e.g. HTTP copy of vmdk files from vCenter or ESXi hosts).


The V2Z migration tool must be installed and configured, with attention to source and target prerequisites. See V2Z migration prerequisites.


Migration using the V2Z tool requires infrastructure preparations.

Contact Zadara’s Operations team for coordinating the migration’s planning and infrastructure setup stages.

Migrate VMWare VMs from NFS share


This is the preferable migration method, in terms of speed and minimal downtime.

In vCenter:

  1. Go to Actions > Migrate.

  2. In Select the migration type, choose Change storage only and click Next.

  3. In Select storage, choose the VPSA NFS that will be connected to the importer VM and click Next.

In the importer VM:

  1. Run this entire procedure with root privileges:

    sudo su -
  2. Format and make a mount point for the disk connected to the importer VM.

    This disk was created earlier as an additional data volume, with free space that amounts to double the used capacity of the largest boot disk.

    In the following example, “X” in “vdX” is the number of the volume block device previously added to the VM:

    mkfs.ext4 /dev/vdX
  3. Update the zCompute toolbox VM’s fstab file (/etc/fstab) with entries:

    # Configure mount point for the disk connected to the importer VM
    /dev/vdX /home/fedora/data ext4 defaults
    # Mount the local NFS share as read-only
    <NFS-server-IP>:/export/<export-name> /home/fedora/nfs_mount nfs user,noauto,ro,nfsvers=3
  4. Remount all entries in fstab:

    mount -a
  5. In the Symp CLI, export the zCompute user’s login token as an environment variable, so that it will be used instead of the user password. This avoids an issue with larger VMs that take a longer time to import.

    export SYMP_TOKEN=`symp -k --url https://<cluster-api-ip> -d <account> -u <user> -p <password> --project <project> login <user> <password> <account> <project> -f value`
  6. Before running the V2Z migration process, change the current working directory to /home/fedora/data:

    cd /home/fedora/data
  7. Migrate the VM using the migrate-vmdk-via-block-device command, with the syntax according to your Toolbox version.


    The syntax of the migrate-vmdk-via-block-device command for Toolbox Fedora 2.3.1 and later differs from the syntax for Toolbox 2.3.0 and earlier.

    • For implementations using Toolbox Fedora 2.3.1 or later, use the syntax that specifies the target VM’s INSTANCE_TYPE:


      v2z vsphere migrate-vmdk-via-block-device [OPTIONS] <VM_NAME> <INSTANCE_TYPE> <BOOT_VMDK_PATH> <OUTPUT_PATH>
        --other-vmdk-paths TEXT
        --config-path TEXT
        --uefi TEXT              [default: False]
        --help                   Show this message and exit.

      For example:

      v2z vsphere migrate-vmdk-via-block-device win2012r2-bios-2disk z4.large /mnt/vmdk_nfs/win2012r2-bios-2disk/win2012r2-bios-2disk-flat.vmdk /home/fedora/data --other-vmdk-paths /mnt/vmdk_nfs/win2012r2-bios-2disk/win2012r2-bios-2disk_1-flat.vmdk
    • For implementations using Toolbox 2.3.0 or earlier, use the syntax that specifies the target VM’s number of CPUs and RAM (in MB):


      v2z vsphere migrate-vmdk-via-block-device <VM_NAME> <CPU> <RAM_MB> <BOOT_VMDK_PATH> <OUTPUT_PATH>  [--other-vmdk-paths <2nd_VMDK_PATH> [n_VMDK_PATH] ]

      For example:

      v2z vsphere migrate-vmdk-via-block-device win2012r2-bios-2disk 2 8192 /home/fedora/vmdk_nfs/win2012r2-bios-2disk/win2012r2-bios-2disk-flat.vmdk /home/fedora/data --other-vmdk-paths /home/fedora/vmdk_nfs/win2012r2-bios-2disk/win2012r2-bios-2disk_1-flat.vmdk

    The examples above, for either Toolbox Fedora 2.3.1 and later or Toolbox 2.3.0 and earlier, will create a zCompute VM with the following:

    • The VMware VM will be migrated to a zCompute VM named win2012r2-bios-2disk

    • The migrated VM on zCompute will have 2 CPUs, 8GB (8192MB) RAM

    • The boot disk to migrate is win2012r2-bios-2disk-flat.vmdk

    • The second disk to migrate (--other-vmdk-paths) is win2012r2-bios-2disk_1-flat.vmdk

    • The output path will be /home/fedora/data

  8. In symp, for VMs that boot using BIOS, run the following configuration:

    vm update --hw-firmware-type bios <vm-id>


    This configuration is required for VMs booting using BIOS, because they migrate as UEFI VMs.

  9. Continue with Post-migration configuration.

Migrate VMs using the VMware API

This is the simplest migration method but slower than the NFS share alternative, thus increasing downtime.

In this migration process, the vSphere API is accessed, and after the vmdk is detected, the vmdk files are migrated into the importer VM using HTTP GET.

The boot disk has to be converted using virt-v2v and additional disks are migrated directly into a zCompute block device, using HTTP GET.

The V2Z migration tool accesses the vSphere API based a configuration file that is populated with the vSphere host and credentials.


V2Z should already be configured for first usage during the V2Z installation and configuration phase, using the v2z config command. See Installing the V2Z migration tool.

The configuration can be viewed and modified using the v2z config command.


  1. Confirm connectivity to vSphere by running the command

    v2z vsphere vm-info <VM_NAME>

    that will display information of a VM that you want to migrate. For example:

    [fedora@fedora-36-zadara-toolbox-d9cbc89-vm ~]$ v2z vsphere vm-info win2016-bios
    Logs for this migration will be available in /var/log/v2z/20220913141833.log
    20220913141833|INFO|ID:cc34dc1c-d447-4d07-9085-45c602d70a2a|Fetching VM information for VM win2016-bios
    20220913141833|INFO|ID:cc34dc1c-d447-4d07-9085-45c602d70a2a|Successfully fetched the VM info for VM: win2016-bios Info: {'name': 'win2016-bios', 'instance_uuid': '503f5ac2-77ae-11f5-a6a1-02c05943c5f7', 'bios_instance_uuid': '423ffb10-d395-5168-9b1f-13d944d0b27f', 'cpu': 1, 'guest_os_name': 'Microsoft Windows Server 2012 (64-bit)', 'memory': 4096, 'power_state': 'poweredOff', 'firmware': 'bios', 'virtual_disk': [{'file_name': '[VPSA_gen3_rnd_prod] win2016-bios/win2016-bios.vmdk', 'datastore_name': 'VPSA_gen3_rnd_prod', 'size_in_kb': 41943040}]}
        "name": "win2016-bios",
        "instance_uuid": "503f5ac2-77ae-11f5-a6a1-02c05943c5f7",
        "bios_instance_uuid": "423ffb10-d395-5168-9b1f-13d944d0b27f",
        "cpu": 1,
        "guest_os_name": "Microsoft Windows Server 2012 (64-bit)",
        "memory": 4096,
        "power_state": "poweredOff",
        "firmware": "bios",
        "virtual_disk": [
                "file_name": "[VPSA_gen3_rnd_prod] win2016-bios/win2016-bios.vmdk",
                "datastore_name": "VPSA_gen3_rnd_prod",
                "size_in_kb": 41943040
  2. Make sure that the temporary directory (usually /home/fedora/data) has double the capacity of the boot vmdk.

  3. Migrate the VM using v2z vsphere migrate-vsphere-vm-via-block-device:

    For Toolbox Fedora 2.3.1 and later, this command automatically determines details such as disk and instance types.


    Usage: v2z vsphere migrate-vsphere-vm-via-block-device [OPTIONS] VM_NAME OUTPUT_PATH
       --config-path TEXT
       --help              Show this message and exit.

    For example:

    v2z vsphere migrate-vsphere-vm-via-block-device win2012r2-bios-2disk /home/fedora/data


    After the VM is created, and while it is powered off, the instance type can be changed.

  4. Continue with Post-migration configuration.

Post-migration configuration

After the VM migration has completed, start up the migrated VM and complete its network setup.

  1. In the zCompute UI, go to Compute > Instances.

  2. Select the migrated VM, and click Start.

    The Attach Interface dialog opens, prompting you to attach a network to the VM. It is possible to specify a subnet, an existing NIC or the VM’s MAC address.

Migrating to a DVS project

VMware VMs that are migrated to zCompute using the V2Z migration process result in VMs in a rich VPC networking type project rather than in the simpler DVS networking alternative.

Tenants that prefer the simpler DVS networking model can further migrate their newly migrated zCompute VPC VMs to a DVS project.

See Migrating a VM to a DVS project in the Networking Guide.