Dell Unity™ Family VNX® Series Data Import to Unity All Flash or Hybrid, or UnityVSA™ System User Guide

Prerequisites for NFS-only VDM import

Import of a VDM and its related file systems from a VNX storage system to a Unity storage system requires the following prerequisites:

• Time is synchronized between the VNX and Unity storage systems. The time difference must be within five seconds. Use the same NTP server on the VNX Data Mover that hosts the source VDM, and the target Unity SPs. See Configuring Time Services on VNX for information about NTP.
  NOTE: The NTP server used must have a stratum number of 5 or less.
• One or more pools must be created and available on the target Unity system to perform a VDM import operation. The pools that are selected should be large enough to hold the source VDM and all its file systems that are migrated.
  NOTE: Compressed data is uncompressed, and deduplicated data is undeduplicated, for migration. Ensure that the target pool has enough capacity to handle these changes in data size. Check on the source VNX for the amount of space savings that compression and deduplication provide for the data. Then determine the amount of space that is required for the uncompressed and undeduplicated data.
• Before creating an import connection, you must configure mobility interface IP address for each SP (A and B) of the target system. (When creating an import session, you select the mobility interface IP address of either SPA or SPB to use as the target import interface. This interface is used to migrate the VNX CIFS server and file systems.)
• Before creating the VDM import session, you must do the following:
  • Create a migration interface on the source Data Mover (for IPv4, use server_ifconfig <server_name> -create -Device <device> -name <nas_migration_interface_name> -protocol IP <ipv4> <ipnetmask> <ip–broadcast> ; for IPv6, use server_ifconfig <server_name> -create -Device <device> -name <nas_migration_interface_name> -protocol IP6 <ipv6/PrefixLength>) and attach the interface to the source VDM to be migrated (using nas_server -vdm <vdm_name> -attach <nas_migration_interface_name>). The interface added on the source VDM to perform migration must be named with the prefix "nas_migraiton_" so that the interface can be clearly identified by the migration process. This interface is used only for the VDM import operation and must not be used as a production interface. After each VDM import session is committed, this interface can be reused by attaching it to the next VDM, and so on.
  • Verify that the physical Data Mover on which the source VDM is located has at least one IP interface configured that is not attached to the VDM being migrated. This IP interface ensures that the source Data Mover can provide uninterrupted Name Services for the remaining file servers. If this additional interface is not present, the VDM import session fails.
  • Ensure the code page that is used on the target Unity system matches the code page that is used on the source VNX system.
• For a source VNX system with two Control Stations, the home directory of a user with the Administrator role, which is used in configuring the import connection, must exist on the primary Control Station of the VNX. For more information, see VNX system with two Control Stations.
• Before starting a VDM import, create an import connection between the source VNX system and the target Unity system.