Basic Guide to Computer Backups Eric Moore Computer Users Group of Greeley September 13, 2008

Why Create a Backup? ● Any hard drive will eventually fail ● Data recovery from a failed hard drive is expensive! ● Restoring a deleted or corrupt file is not always possible ● Your data may be time-consuming to recreate (if even possible) ● You depend on your computer for your livelihood ● You need to keep multiple revisions of a file

Backup Media ● Internal Hard Drive – 500 GB of storage – About $0.20 per GB – Fast backups and restores – Not portable! ● External Hard Drive – 500 GB of storage – About $0.20 per GB – Slower than internal hard drive – Portable ● CD-R – 700 MB of storage – About $0.23 per GB – Portable – Inconvenient for multi-GB backups

Backup Media (cont.) ● DVD-R – 4.7 GB of storage – About $0.05 per GB – Portable – More convenient than CD-R ● DVD+R Double Layer – 8.5 GB of storage – About $0.14 per GB – Portable – More convenient than DVD-R ● USB Flash Drive – 4 to 32 GB of storage – About $2.50 to $3.00 per GB – Greatest Portability – Pricey

Backup Methods ● File and Folder Backup – Select group of files and folders – Less time to perform – Less storage space – For small, daily backups of your data ● Drive Image – Entire partition or hard drive – More time to perform – More storage space – For complete restoration of your computer

Types of Backups ● Full Backup ● Incremental Backup ● Differential Backup ● Copy Backup

Full Backup ● Captures every selected file and folder ● Marks every item it touches as being backed up ● Requires the most space and time

Incremental Backup ● Captures files and folders created or modified since last full or incremental backup ● Marks every item it touches as being backed up ● Requires less space and time to complete ● Requires more time (and care) to restore

Differential Backup ● Captures files and folders created or modified since last full backup ● Does not mark anything as being backed up ● Requires more space and time than an incremental backup ● Requires less time to restore

My Recommendations ● Method and Media – Disk image for greatest safety in case of disaster – External hard drive and/or flash media ● Frequency – Full backup at least once a month – Incremental or differential once a day ● Redundancy – Create copies to different media – Store at least one encrypted copy off site or online ● Test for Reliability – Verify scheduled backups are actually run – Try restoring some files and folders