Microsoft SQL Server

Production End and DR End

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

1. For the SQL Server cluster, to ensure the uniqueness please set the different SQL Server network name when creating production cluster and DR cluster.
2. In a WSFC cluster, you need to add Authenticated Users permission to SQL Server database.
   1. On the database management page, select Security > Logins, right-click New Login.
   2. In the dialog box that is displayed, click Search.
   3. In the Select User or Group dialog box that is displayed, select Authenticated Users.
   4. Click OK.

Production End

1. Check the authentication method of SQL Server database at the production end.

   Hybrid authentication must be adopted for SQL Server database, or the connection to the database fails.

2. Ensure that the name, user name, and password of the SQL Server database at the production end meet the following requirements:
   • The database name can contain only letters, digits, and special characters including _ - @ # $ *
   • The database user name can contain only letters, digits, and special characters including _ - @ # $ *
   • The database password can contain a maximum of 32 characters, including letters, digits, and hyphens (!). %_- @ # $ *

3. Check the VSS service status of the application host where the SQL Server database at the production end resides.

   eReplication Agent uses the VSS service to ensure consistency between SQL Server databases. Therefore, the VSS service must be enabled when eReplication Agent is working.

4. Check database files at the production end.

   Data files and log files in databases must be stored on storage array LUNs.

5. Grant the connect permission to database user guest.
   

   The permission granting is applicable only to the production environment where SQL Server 2012 (both single node and cluster) is in use.

   1. On the database management page, select the database that you want to configure and click Properties.
   2. In the Database Properties dialog box that is displayed, click Permissions.
   3. Click Search.
   4. In the Select Users or Roles dialog box that is displayed, enter guest and click Check Names to check the name validity.
   5. Click OK.
   6. On the Explicit tab page, select Connect.

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 SQL Server databases are the same as that at the production end.
   	The versions of SQL Server databases are the same as that at the production end.
   Database	The names, instance names, user names, and passwords of databases are the same as that at the production end.
   	The locations that data files and log files in databases are stored are the same as that at the production end.
   SQL Server cluster	The names of the resource group and the disks in the resource group at the DR end are the same as those at the production end.
   	The failover clusters of the same name do not exist on the same network.
   	The disk resources where database file resides must be in Maintenance mode in the cluster manager before the database test or recovery.
   	Before testing or restoring the database, manually bring the database offline and ensure that the disk resource where the database file is located is in the Maintenance mode in the cluster manager. Otherwise, disk resources may fail to be mounted when the database is started.
   	After the DR cluster host restarts or resets, or cluster services reset, check the status of all resources in the failover cluster manager. For disk resources whose status is Offline and database disk resources for which database DR will be performed, set the status to Maintenance.

2. Set databases on the DR end offline.
   

   Do not close instances to which the databases belong.

Storage End

• Check the storage environments of the production end and the DR end.
  1. 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. In the HyperMetro (SAN) and asynchronous replication (SAN) or HyperMetro (SAN) and synchronous replication (SAN) or HyperMetro (SAN) + HyperVault DR (SAN) scenario. If multiple LUNs are used, related remote replications must be added to one consistency group.
• Check the storage configurations of the DR end.
  1. Delete the LUNs mapped to the DR host or test host at the DR end and ensure that the corresponding drive letters are not occupied by other LUNs.
     

     In the SQL Server cluster, the cluster must be in Maintenance mode before deleting the LUNs mapped.

  2. 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.
  3. 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. In a cluster, add the logical host to the host group.
  4. 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.
  5. 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.