Backup to a Remote Tape Device

With BRBACKUP and BRARCHIVE you can back up files of the Oracle database to a remote tape device that is connected to a UNIX host in the network. You can use several tape devices on the remote host for backup and these are used in parallel.

The UNIX versions of the local and remote hosts need not be identical. For example, if the database runs on an HP-UX host, you can perform the backup on an AIX host.

We only recommend remote backup when your network is very fast and stable. Therefore, we do not recommend this procedure for production systems in most cases. However, you can use it to back up test systems.

Prerequisites

• 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|rsh date.: only one line with the output of the date command should be displayed.

• For a successful remote shell call, check that there is an entry as follows in the
.rhosts file, which is in the HOME directory of the remote operating system user on the remote host:

where:

is the host where the database runs

is the operating system user who starts the backup

For more information, see your operating system documentation.

Activities

The individual database files are transferred to the remote host using a remote shell call, called a "pipe." You define the remote host with the init.sap parameter remote_host and the user with the remote_user parameter.

On the remote host the files are written to tape using the UNIX dd command. You define the dd command in the profile init.sap, as in the following example:

copy_in_cmd = "dd bs=64k if=$"

copy_out_cmd = "dd bs=64k of=$"

The number of parallel copy processes normally corresponds to the number of backup devices available. You can change this setting with the init.sap parameter exec_parallel or the command option -e|-execute.