Procedures for Imaging Optical Media

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Optical Media Imaging – Draft Procedures

Summer/Fall 2010

Objectives

• Initial backup of acquired or legacy optical media
• Authenticity

Naming convention

Example:

• D001AddMSS1788_Title_Proper[21]C.iso

Where:

• D= Duplicate
• 001= Duplicate number – sequential per fonds
• AddMSS#### = AddMSS Number
• Title_Proper = Title assigned by the Creator with underscore (_) in place of spaces
• If disk is numbered, include the number in brackets = [21]
• If result is corrupt, include “C” at the end of the title. NO LONGER ACCURATE: This was the method we used to identify I/O errors when just using dd. Now, we immediately redo the image using ddrescue should there be an I/O error message after running dd.
• If result is corrupt (I/O or other error) and ddrescue is used to make a new image, append title with “res” to record that it has been rescued.

Procedure

• Attach external 1TB drive formatted HFS+ (Mac OS Extended – NOT JOURNALLED). This is specific to VANOC since we’ll be appraising the photos/videos on the Mac. In future, we’ll prefer using Ubuntu formatting (ext2) or FAT (up to 4GB).

• In terminal, enter

Sudo chmod 777 /media/Transfer## This allows the user to write to the HFS+ drive

• Create folder on attached drive. Folder name should be reflective of the group of optical media to be imaged

• Create index in OpenOffice Spreadsheet. See template: DOC/2010/

• On Duplication machine, we used to use Brasero or other open source imaging software prior to using command line dd on the first set of disks from VANOC. Now we use command line interface in terminal [ dd if=/dev/sr0 of=media/usb#/AddMSS####_Name/D###AddMSS####_Name.iso where usb# is the directory on the external drive (if you don’ t know, type “mount” to list) and sr0 is the mount point for the CD/DVD] to create iso images and place them in folder.

• If, after running dd, there has been an I/O error, run ddrescue [ ddrescue –e ##oferrorsmax infile outfile logfile ]

• Update index file (OpenOffice Spreadsheet) with application used, title before/after, drive name, date, notes, metadata, etc.

• Add checksum of the iso file to the checksum text file in folder (gets created when the first checksum is made) when each image completes.

• Enter drive information in the External Drive Tracking spreadsheet VanDocs (DOC/2010/045979) and move Index spreadsheet to VanDocs.