# Information About Offline Data Restore Tool

The Offline Data Restore Tool (ODRT) is a standalone Linux application and is a comprehensive solution for recovering encrypted data on tape volume groups when the MSM-18/4 module or the Cisco MDS 9222i switch is unavailable. The ODRT reads the tape volumes, encrypted by SME, and decrypts and decompresses the data and then writes clear-text data back to the tape volumes.

Figure 0-8 shows the topology supported by the ODRT.

Figure 1-8 Offline Data Restore Tool (ODRT) Topology

The encryption and decryption of data works in the following two steps:

• Tape-to-disk– The ODRT reads the encrypted data from the tape and stores it as intermediate files on the disk.

• Disk-to-tape– The ODRT reads intermediate files on the disk, decrypts and decompresses (if applicable) the data and writes the clear-text data to the tape.

The decryption key is obtained from the volume group file which you need to export from the Cisco Key Management Center (KMC).

The ODRT feature is invoked by entering the odrt.bin command from the Linux shell.