In Import phase, lesser activities are required. First step is to check the size of your file system so that sufficient storage is available for the target environment. As you generally deploy a certified SAP HANA appliance, this will be taken care automatically.
Before starting with the import, you should also set the log mode of the SAP HANA system to overwrite the existing log files during import. Otherwise migration may crash due to storage medium of log files becoming full in capacity.
It is also important to set the log mode back to original setting after the migration is completed. The log files are generated only after you perform a backup of the database in future.
Setting of log mode in SAP HANA system
Open SAP HANA Studio and double click your SAP HANA system. Go to the configuration tab in the ADMINISTRATION perspective. Enter the search term ‘log-mode’ in the filter box or expand the tree GLOBAL.INI – PERSISTENCE.
An input window opens if you double click on LOG-MODE. For SYSTEM, set the log-mode parameter to OVERWRITE and then click SAVE.
In this setting, the logs are overwritten periodically (redo logs) and the system does not wait for backups. Hence, it is not possible to do a point in time recovery of the system. Thus, this setting should never be used in Production systems.
The backup mechanism continues in the background unaffected by this change. It copies the log segments to the intended medium (basepath_logbackup parameter) every 15 minutes by default.
You should temporarily stop this process during an SAP BW on SAP HANA migration. To do so, choose the ENABLE_AUTO_LOG_BACKUP parameter under GLOBAL.INI-PERSISTENCE in the same view, and set it to NO. Save this setting.
Setting up the system users
If you deploy Windows as the operating system for your future application server, you must decide whether the Windows system users are to be created locally or as part of a domain.
If you are doing parallel import and export, it will be useful if there is domain user. This simplifies the access to export directory which was created locally in the original system. The access to the export data must always be provided for <SID>adm user during the import run. This applies to all the operating systems. If you are unsure about the correct configuration, contact your network expert.
You can now start with the import if the log mode was set correctly and the remote access to the export directory is provided.