SAP HANA

Production End and DR End

Check the database environments of the production end and the DR end where SAP HANA databases reside.

1. When a database environment is configured at the production end where hosts running Suse12 or RedHat7 are deployed, the mount points of the file system used by the database cannot be nested. For example, mount points /testdb/ and /testdb/database1/ are nested.
2. Before configuring a SAP HANA database, you must obtain the instance name, user name, and password of the SAP HANA database.

   The instance name is the SAP HANA database instance name. The user name is that of the system user of the SAP HANA database instance. Usually, the user name is the same as the instance name. The password is that of the system user.

3. Check whether the password of the SAP HANA database meets the requirements for input characters. If other special characters are entered, the database will fail to be authenticated during creating a protected group.

   Supported characters: only letters, digits, and special characters including _#%^+-.,~@$.

4. Check that the production and DR hosts running the SAP HANA database have the same name.

   The production and DR hosts must have the same name. If their names are different, change the DR host's name to the production end's name.

Production End

1. Check the database configuration at the production end.

   eReplication of the current version supports DR for SAP HANA databases on Suse12 and RedHat7. To enable eReplication to perform DR for SAP HANA databases, the SAP HANA databases must meet the following requirements:

   • Installation directories of SAP HANA instances must reside on local disks or independent storage devices and cannot reside on the same devices as databases for which DR is intended.
   • Data files in the SAP HANA databases for which DR and protection are intended must be stored on LUNs provided by Huawei storage devices.

DR End

1. Check the database environment at the DR end.
   

   If the database environments at the DR end and production end are not the same, the user should deal with it to make sure that the DR end and production end have the same database environments.

   Table 1 describes the lists configuration requirements.

   Table 1 Configuration Requirement of the Database on the DR End

   Check Item	Configuration Requirement
   Installation	The operating system and its edition run by SAP HANA databases are the same as that at production end.
   	The versions of SAP HANA databases are the same as that at the production end.
   Configuration	The cluster where the SAP HANA databases reside at the DR end has the same configuration as that at the production end. The two clusters must have the same resource configuration and dependency among resources.
   Instance	The instance names, numbers, user names, and passwords of databases are the same as that at the production end.
   	The user groups to which users of SAP HANA database instances belong are the same as that at the production end.
   	The installation directories of SAP HANA instances at the DR end reside on local disks or independent storage devices.
   	The SAP HANA databases to be recovered are created under SAP HANA instances at the DR end and ensure that the created databases meet the following requirements: Names of databases are the same at the DR and production ends. Storage paths (file systems) used by databases are the same at the DR and production ends. Names of logical volumes used by databases and volume groups to which logical volumes belong are the same at the DR and production ends.

2. Close databases on the DR end.

   After checking the database environments, close databases on the DR end before creating a recovery plan.

   For a single SAP HANA device, close the database directly.

3. Modify the configuration file of the database at the DR database end.

   After shutting down the database at the DR end, modify the value of parameter id in the nameserver.ini configuration file of the database at the DR end to keep the value consistent with that of the database at the production end.

   

   This value is used to identify storage devices of the database.

   1. Use PuTTY to log in to the server at the production end as user root.
   2. Run the following command to prevent PuTTY from exiting due to session timeout:

      TMOUT=0

      

      After you run this command, the system continues to run when no operation is performed, resulting a risk. For security purposes, you are advised to run the exit command to exit the system after completing your operations.

   3. Run the following command to view the value of id in the nameserver.ini configuration file. SID is the value of SAP HANA System ID set when you create a database. Set the value based on the site requirements.

      cat /usr/sap/SID/SYS/global/hdb/custom/config/nameserver.ini

   4. Use PuTTY to log in to the server at the DR end as user root.
   5. Run the following command to prevent PuTTY from exiting due to session timeout:

      TMOUT=0

      

      After you run this command, the system continues to run when no operation is performed, resulting a risk. For security purposes, you are advised to run the exit command to exit the system after completing your operations.

   6. Run the following command to open the nameserver.ini configuration file: SID is the value of SAP HANA System ID set during creating a database. Set the value based on the site requirements.

      vi /usr/sap/SID/SYS/global/hdb/custom/config/nameserver.ini

   7. Press i to enter the editing mode and find parameter id. Modify the value of id to be that obtained from Step 3.3.
   8. Press ESC to enter the browsing mode, and then press Shift and : simultaneously. Run wq! to save and exit.

4. Replace the database SSFS verification files used at the DR end with those used at the production end.

   /hana/shared/SID/global/hdb/security/ssfs/SSFS_SID.DAT

   /hana/shared/SID/global/hdb/security/ssfs/SSFS_SID.KEY

   

   SID indicates the value of SAP HANA System ID specified during the database creation.

Storage End

1. Check the storage environments of the production end and the DR end.

   Check the remote replication between the production end and the DR end. Before using remote replication to protect objects at the production end, ensure that the remote replication is normal between the production end and the DR end.

2. Check the storage configurations of the DR end.
   1. Check whether all file systems used by the database to be recovered are unmounted from the DR host.
   2. On the DeviceManager, check that secondary LUNs of the remote replications used by DR databases are not mapped to any host, host group, or mapping view.
   3. For the Linux DR host, check whether all volume groups of the logical volumes used by the database to be recovered are deactivated and exported from the DR host.
   4. After setting up an application environment on the DR end, delete the mapping between the host and the storage LUNs or volumes that store the data files and log files of the application.
   5. If the DR storage is the S5000 series or T series V1, map the initiator of the physical DR host to the logical host of the DR storage.
   6. If the storage is T series V2R2 or later or 18000 series, the storage support automatically add host and storage mapping function. If the connection between the storage device and the host initiator is normal, the hosts, host groups, LUN mappings, and mapping view will be created in the storage device automatically.
   7. If the DR storage is T series V2 or later or 18000 series, the DR host can belong to only one host group that belongs to only one mapping view. The remote replication secondary LUN that corresponds to the storage LUN used by the protected applications can belong to only one LUN group, and the LUN group must belong to the same mapping view as the host group.