4 Preparing for Data Migration
Use the information in this chapter to ensure all necessary tasks are performed and considerations are understood before beginning a migration.
Data Migration Considerations
Before migrating data using 3PAR Online Import for EMC Storage, be aware of the following general considerations, system requirements, and other tasks associated with planning, host configuration, and network and zoning requirements.
General Considerations
•LUNs and hosts can be implicitly added to the migration, even if they are not specified by the input.
•Only volumes presented to Fibre Channel hosts can be migrated. Volumes presented to iSCSI or FCoE hosts cannot be migrated.
•All hosts and LUNs in the source groups are migrated. If there are multiple hosts or LUNs in the configuration, they all end up in a single CPG.
•When a cluster is being migrated, all the hosts in the cluster must be moved at once.
•HP 3PAR host persona/host OS: EMC Storage arrays do not implement specific OS settings when registering host initiators on the EMC Storage array. During migration, online import cannot determine the host OS when migrating the hosts to the HP 3PAR StoreServ Storage. All hosts that are being created on the HP 3PAR StoreServ Storage during EMC migration are set by default to host persona 2. Consider changing the HP 3PAR host persona/host OS to the appropriate setting before enabling access to the HP 3PAR array.
•LUNs identified for migration should not be part of any other current application jobs. For example, make sure the LUN is not part of a replication job or backup job.
•The LUN limit for offline migrations is 25. The maximum number of volumes that can be migrated with MDM or an online migration is 255. See “Aborting a Migration” (page 55)
•A createmigration command cannot simultaneously contain a host and a LUN for migration.
•Only one createmigration is allowed at a time because 3PAR Peer Ports can only be in one EMC Storage Group at a time.
•When a volume on the source EMC Storage system is migrated, an
•Only one EMC Storage system at a time can be attached as a source to the destination HP 3PAR StoreServ Storage system.
•EMC volumes cannot be migrated if they are larger than 16 TB, the maximum volume size on the HP 3PAR StoreServ Storage system.
•EMC volumes cannot be migrated if they are less than 256 MB, the minimum volume size on the HP 3PAR StoreServ Storage systems.
•Snapshots become standalone objects on the destination HP 3PAR StoreServ Storage system. LUNs that have been migrated cannot be part of a replication group.
30 Preparing for Data Migration