Prerequisites

Use the prerequisites for workload migration based on single-system or single-cloud and multi-system or multi-cloud.

Single-system or single-cloud workload migration

  • Environment level prerequisites for both source and target systems:
    • Both the source and target system must run on Generation 4 or higher systems.
    • Both source and target are at a minimum level of Version 2.3.4.
    • Make sure that the source and target vCenter servers have different instance UUID. To refresh or reset the UUID, see Configuring the virtual manager external IP address. If you encounter errors, see stage 2 of Troubleshooting.
    • For IBM® Cloud Pak System migrations, an entry of vCenter credentials must exist for the source and target cloud group. Add the entry in both IBM Cloud Pak System source and target. For the actual procedure, see Configuring external application access.
    • For IBM Cloud Pak System migration, make sure that you configure the virtual manager external IP address on both systems. Also, make sure that you configure a distinctive FQDN on each of the involved IBM Cloud Pak Systems. For the actual steps, see Configuring the virtual manager external IP address.
    • You must have administrator privileges on both the source and target system.
    • The vCenter ID of the source system and target system must be the same. It is a VMware® limitation.
    • The patterns in both source and target must not have any pending warnings.
  • Make sure that the MAESTRO_JAVA_HOME environment variable is set in the source Windows virtual machine that is targeted for migration. The value for this variable must point to the IBM Java SDK runtime that is installed on the virtual machine, which is, C:\Program Files (x86)\IBM\Java80\sdk.
  • The following software must be the same for both source and target systems:
    • Virtual images (same version)
    • Virtual System pattern
    • Pattern Type (same version)
    • Build ID (same version)
    • Plug-ins
    • Component types
    • Script packages
    • IP Groups are configured for the virtual machines of both source and target cloud groups such that the Subnet, Gateway, and VLAN ID are the same.
      Note: All IPv4 addresses of the virtual machines are retained on the target virtual machine after migration. However, the IPv6 addresses change after the migration on the target virtual machine.
  • Source level prerequisites:
    • Take a backup of the virtual machines before you start the migration. If problems occur in migration, the backup helps to restore the virtual machines.
      Note: Though snapshots are migrated from source to target, you cannot restore a snapshot that is taken on the source after the virtual machine is migrated to the target.
      Important: If the target system does not allow certain number of vCPUs to be deployed, then the virtual machine cannot be migrated with that number of vCPUs to this system. Make sure that you first check and compare the target and source system values and then trigger the migration process.
    • For the Virtual System Instance under migration, avoid 100% CPU usage of these virtual machines. You can achieve this CPU usage by either temporarily stopping applications on the virtual machines or by reducing the amount of CPU activity that is done by these applications. But you can also temporarily add more vCPU resources if possible.
    • If the same version of the plug-ins that are deployed in the source Virtual System Instance is needed in the migrated Virtual System Instance, that is, if you do not want to upgrade to the current version of the plug-in, then you must deploy the source Virtual System Instance with the Lock all plug-ins option that is selected in the Lock option for plug-in usage section of the pattern editor. If you select the Unlock plug-ins or the Lock all plug-ins except Foundation plug-ins option, the plug-ins of the migrated Virtual System Instance are upgraded to the current version of the plug-in.
  • Instance level prerequisites:
    • Make sure that the Virtual System Instance is in running state before migration.
      Note: Even if the Virtual System Instance is in maintenance mode in the source, the migrated instance in the target system is in running state.
  • Target level prerequisites:
    • Make sure that the IPV4 address is added to each of the compute nodes in the target system.
    • Make sure that the hypervisor version of the compute node is the same in both the source and target system.
    • The IP addresses of a Virtual System Instance are dynamically created during the migration process, so make sure that these IP addresses do not exist on the Target IP group before migration.
  • Go through the known issues or troubleshooting information before you proceed with the migration. For more information, see Known issues and Troubleshooting.

Multi-system or multi-cloud workload migration

Apply all the single-system or single-cloud workload migration prerequisites on all the four systems (two target and two source systems) for multi-system or multi-cloud workload migration.

Apply these additional prerequisites for multi-system or multi-cloud workload migrations. Make sure that:
  1. The multi-system or multi-cloud set up is working fine on the target and source set system multi-cloud pair. Go to System > Management Domain Configuration from the IBM Cloud Pak System user interface and check whether the configuration is in Available state or not.
  2. The same LDAP configuration is in place on both the source and target multi-cloud system pair.
  3. The LDAP user that was used to create the Virtual System Instance on the source multi-cloud rack is also available on target MR rack. Do the migration by using this same user only, as the same parameter is used everywhere to login on the source and target multi-cloud system pair.
  4. Migration might fail if a non-LDAP user triggers the migration.
  5. The deployment is accessible from the LDAP user that is used for migration on the target multi-cloud system.
  6. Both the source and target multi-cloud system pairs must be on IBM Cloud Pak System Version 2.3.4.
  7. The LDAP user that is used for migration must have all the privileges to fetch the VMware Virtual Center (vCenter) credentials and to do the deployment on the target multi-cloud system pair.
  8. Add the same number of cloud groups in the target environment profile, which are present in the source environment profile, too. You need the same configuration on the source and target (cloud groups, environment profile, and IP groups) systems.