Lecture #12 Backup and Restore

Learner Outcomes

• Choose an appropriate backup strategy given a set of requirements
• Perform full, incremental and differential backups
• Restore a system from one or more backup archives
• Describe the issues around pathnames and symbolic links with respect to backups.

Activities

1. Exercises 9.3, 9.4, and 9.5 from the back of the chapter.
2. Demonstration of backing up a file system remotely.
3. Perform a full system backup of the virtual Linux Install machine
4. Lab 8

Assignment

1. Read Chapter 8 and sections 1, 2, and 4 of Chapter 10
2. Do Lab 9

System Backup and Restore

1. The Backup Process
   • Backup Policies
   • Devices
   • Problems with Backup Programs
   • Restoring Data
   • File Permissions, Types, and Structures
   • Defragmentation
   • Protecting the Backup Media
   
   
2. Backup Devices
   • Tape Devices
     • Problems with tapes
     • The buffer utility
     • Tapes and random file access
   • Writable CD and DVD
     • Limits of optical media
   • Other Removable Media Devices
   • RAID Arrays
   
   
3. Types of Data
   • System Data
     • Basic information to set and run the system
   • Application Software
     • Best to reinstall from source installation disks
   • Databases
     • Most important data types
   • User Data
     • Includes site work
   • User Data and Home Directories
     • Includes e-mail, files from home directory for personal use
   
   
4. Methodologies
   • Epoch
     • Arbitrary time interval that denotes a beginning
     • Beginning of backup process
   • Incremental
     • All files that have been added or changed since epoch
   • Differential
     • Similar but easier than incremental, only uses two tapes
   • File Ghosting
     • Anomaly of the backup and restoration process
   
   
5. Archive Utilities
   • dump/restore
     • Oldest and most trusted backup utility
     • Searches for new or changed files and writes them to device
   • tar
     • Used to archive or backup files, directories, hard disks
   • cpio
     • Copy input/output
     • tar files and archives can be used without unarchiving
   
   
6. Compression Utilities
   • compress
     • Traditional compression utility
   • zip
     • Used for compressing, archiving files into single archive
   • gzip
     • Used for compressing, uncompressing files one at a time
   • bzip2
     • New, slower, but better compression device
   
   
7. Backup Software Packages
   • AMANDA
     • AMANDA's features
     • Installation
     • AMANDA's administration
     • Additional resources
   • Kbackup
     • Scheduling operations
     • MULTIBUF
     • Creating a backup
     • Restoring backups
   • UNiBack
   • Taper
   • Arkeia

Relevant Commands and Files