Enable the system replication function for the SAP HANA on the secondary server.

Before you enable system replication for the HANA database on the secondary server, ensure that the network connection is normal and that the HANA database has been started.

The procedure is as follows:

1. Log in to the secondary HANA node as the root user. Run the su - s00adm command to switch to the HANA database user s00adm (replace s00 with the actual database SID in lowercase).
2. Run the HDB start command to start the HANA database and wait till the database is successfully started.

   hw00002:~ # su - s00adm
   s00adm@hw00002:/usr/sap/S00/home> HDB start
   StartService
   Impromptu CCC initialization by 'rscpCInit'.
   See SAP note 1266393.
   OKOK
   Starting instance using: /usr/sap/S00/SYS/exe/hdb/sapcontrol -prot NI_HTTP -nr 00 -function StartWait 2700 2
   12.10.2015 15:05:28
   StartOK
   12.10.2015 15:06:26
   StartWaitOK

3. After the HANA database is started successfully, run the hdbnsutil -sr_enable command to enable the system replication function. If "successfully enabled" is displayed, the system replication function is successfully enabled.

   s00adm@hw00002:/usr/sap/S00/home> hdbnsutil -sr_enable
   nameserver is active, proceeding ...
   successfully enabled system as system replication source site
   done.
   s00adm@hw00002:/usr/sap/S00/home>

4. Run the hdbnsutil -sr_state command to check the database system replication status. If the database mode is sync, this node is used as the node that synchronizes data with the DR node.

   s00adm@hw00002:/usr/sap/S00/home> hdbnsutil -sr_state
   
   System Replication State
   ~~~~~~~~~~~~~~~~~~~~~~~~
   
   online: true
   
   mode: sync
   operation mode: logreplay
   site id: 2
   site name: hw00002
   
   
   is source system: true
   is secondary/consumer system: true
   has secondaries/consumers attached: false
   is a takeover active: false
   active primary site: 1
   
   primary masters: hw00001
   
   Host Mappings:
   ~~~~~~~~~~~~~~
   
   hw00002 -> [hw00002] hw00002
   hw00002 -> [hw00001] hw00001
   
   
   Site Mappings:
   ~~~~~~~~~~~~~~
   hw00001 (primary/primary)
       |---hw00002 (sync/logreplay)
   
   Tier of hw00001: 1
   Tier of hw00002: 2
   
   Replication mode of hw00001: primary
   Replication mode of hw00002: sync
   
   Operation mode of hw00001: primary
   Operation mode of hw00002: logreplay
   
   Mapping: hw00001 -> hw00002
   done.
   s00adm@hw00002:/usr/sap/S00/home>