Backup to a Remote Tape Device 

BRBACKUP/BRARCHIVE can back up files to a remote tape device that is connected to a UNIX host in the network.

The UNIX versions of the local and remote hosts do not need to be identical. If, for example, the database runs on an HP-UX host, the backup can be performed on an AIX host.

The individual database files are transferred to the remote host via a remote shell call (via "pipe"). The remote host is defined in the init<DBSID>.sap parameter remote_host , and the appropriate user is defined in the parameter remote_user .

Make sure that no additional messages (that is, not belonging to command output) are issued on remote login (for example, from .login or .cshrc ). Test the command remsh <host_name> date : only one line with the output of the date command should be displayed.

A prerequisite for a successful remote SHELL call is for example the following entry in the file .rhosts , which is in the HOME directory of the remote operating system user on the remote host:

<local_host_name> <local_user_name>

<local_host_name> is the host where the database runs.
<local_user_name> is the operating system user who starts the backup.

On the remote host, the files are written to tape using the UNIX dd command. The appropriate dd command is defined in the profile init<DBSID>.sap .

copy_in_cmd = "dd bs=16k if=$"
copy_out_cmd = "dd bs=16k of=$"

You can use several tape devices on the remote host for backup. These are used in parallel.

Backup on a remote tape device is only appropriate when the network is very fast and stable. Therefore, this procedure is usually not recommended for production systems. Test databases, on the other hand, are entirely suitable for remote backups, for example, backing up the test database remotely using backup devices connected to the host where the production database runs.

The number of parallel copy processes normally corresponds to the number of backup devices available. This setting can be changed with the init<DBSID>.sap parameter exec_parallel or the command option -e|-execute .

Backup to a Remote Disk