RMAN Recovery In Oracle 11g : Backup Database To Tape

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Question :

On issuing this command:

RMAN> backup device type sbt tablespace <tablespace_name>;

we are getting the following error:

ORA-19554: error allocating device, device type: SBT_TAPE, device name: 
ORA-27211: Failed to load Media Management Library

How to overcome this error?

Answer :

The “device” in RMAN is a misnomer, it should be really called “storage”.

The “sbt” (synonym of “sbt_tape”) is a misnomer again, as it has NOTHING to do with any tapes, it should be simply called “non-rman”. This is just an empty placeholder, to be filled with any “plugin”; the plugin is called by Oracle either the “Media Manager library” or SBT_LIBRARY. This plugin allows rman to store and retrieve files through it, so rman only tells that it needs a file handle “xyz” (file is identified by a string handle) and doesn’t need to know how the file is delivered, from tape or anything. The plugin is normally a part of an independent backup software, such as IBM TSM or Symantec NetBackup or many others. Oracle provides a simple emulator SBT_LIBRARY=oracle.disksbt for testing.

Since you didn’t fill that placeholder with any “Media Manager library”, you receive an error message as expected.

If you are not using a Tape Device for your backup tasks, then you might be using disks?
Either way, try assigning a device/path to the SBT device before you perform your backup:

Start RMAN from your prompt

rman ENTER

Connect to your target

RMAN> connect target /

Allocate a path you your SBT device (this is for a path device):

RMAN> allocate channel for maintenance device type sbt parms 'SBT_LIBRARY=oracle.disksbt, ENV=(BACKUP_DIR=<your backup directory>)';

Issue your backup command without the SBT device:

RMAN> backup tablespace <tablespace_name>;

I once read:

You should configure default devices and channels in advance of running RMAN Backup.
RMAN Backup | SS64.com

Good luck!

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