Backup Rotation Schedule Basics

Backup rotation schedule is an essential basis of the whole backup strategy especially concerning corporate data backup and recovery used by enterprises. It is widely known that having only one copy of important information is asking for trouble. You have to keep multiple copies and one of them in secure off-site storage. Backup schedule is usually using a combination of partial backups interspersed with full backups to reduce backup time and capacity usage.

Most known and simple partial backup method is differential backup which allows saving all data changes made since last full backup. Due to backup strategy it takes more storage capacity, but is much faster to restore backed up information if it is necessary. Incremental backup is a little bit more complicated method allows backing up changes made since last incremental backup instead of full. This method helps to reduce storage capacities used to keep backup files, but process of backed up data restoration is relatively slow.

Top backup rotation schedules used for tape backup are mostly Grandfather-Father-Son (GFS) and Tower of Hanoi. GFS is based on using three sets or generations of tapes. Monthly full backup is grandfather, weekly full backup is father and a son set for partial everyday backups. Grandfather tapes are stored off-site while “younger” generations stay in backup rotation. Tower of Hanoi is based on mathematic puzzle of the same name and provides an ability to increase generations’ depth.

No matter which backup rotation schedule you will select according your corporate data backup strategy. The most important requirement is to have 24/7 access to your backups, though it is provided by every quality online backup service.

Remote data backup planning issues

Remote data backup requires careful preparation and planning stage before you can be sure that performance will be adequate. Understanding of how much data you need to backup in a typical evening is the first important issue to be considered when planning remote backup strategy. When you know approximate data level to backup daily it’s time to select remote backup service which fits your budget and offering an adequate bandwidth.

Another factor gaining importance for remote data backup is data deduplication or intelligent compression as it also called. Typical remote backup may create many copies of the same file. Data deduplication used to avoid creating redundant information. It only makes one reserve copy of the file and provides pointers to other file iterations. So if you have 100 copies of 1 MB file, ordinary backup will use 100 MB of storage for them, while data deduplication need storage for 1 MB file and references for additional copies. 1 MB instead of 100 MB is a difference which makes reasonable enough to use only data deduplication supporting remote data backup.

The third issue with planning remote data backup strategy is possibility of connection failure. Business impact of link problem must be identified to make plans for minimization negative effects. Temporary connection problems must be corrected by repeat of remote backup attempt several hours later when the connection will return.

See also remote backup