Understanding Backups Part 1: Backup Types
As you know, at Cranston IT we are big believers in backing up data. That’s because sooner or later you will lose data. Either your hard drive will crash, you will accidentally delete some files, your computer will get lost or stolen, or your computers will get caught in a fire, flood, or some other natural or man-made disaster.
It’s a rule. If you have your data in one place, you will eventually lose it. If you have your data in two places, it is unlikely that you will lose it. If you have your data in three places, it is very unlikely that you will lose it. So how many times should backup your data, is simply a question of how critical is your data.
It’s a rule. If you have your data in one place, you will eventually lose it. If you have your data in two places, it is unlikely that you will lose it. If you have your data in three places, it is very unlikely that you will lose it. So how many times should backup your data, is simply a question of how critical is your data.
When backing up data there are three parts of the process and several different options for each part of the process. There is the type of backup, the backup software used and the location or destination of the backup. Today we will look at the three types of backups. They are Full, Incremental and Clone. These three types have some overlap but basically they are different.
Full backups are complete copies of the data you want to back up. For example, if you wanted to make a full backup of your documents folder you could simply select your documents folder and drag and drop it onto an external hard drive. Your Mac would create an exact copy of everything your documents folder on the external drive.
Full backups can easily be created manually by dragging and dropping the files and folders you would like to back up. The problem with manual backups is that people forget to do them. Invariably, when you need to back up you realize that a backup has not been done anytime in the near past. We recommend using software to automate the backup process regardless of what type of backup you are doing. Backup software helps to ensure the backups run according to schedule and organizes the backed up data.
Incremental backups can only be done with backup software. The first time an incremental backup runs it creates a full backup. The second time an incremental backup runs it only looks for files that have been changed or created since the first backup. It then adds only those files to the backup. Incremental backups are valuable for a few reasons.
One, they take up less space than full backups. Since only the data that has changed since the last backup is backed up, subsequent backups after the initial backup are much smaller. This allows you to store more backups on your destination device.
Two, incremental backups allow you to go back in time and see multiple variations of a file and find files that may have been deleted at some time in the past. An incremental backup builds a history of activity on your computer that can be accessed as needed at a later date.
Three, since the backup does not have to back up all data every time the time it takes to run the backup is significantly less than a full backup. You can then run these backups more frequently. It’s not uncommon to run incremental backups once an hour.
The third type of backup is a clone backup. Clones also require special software to run. A clone is an identical copy of everything on your hard drive. This includes not only your user data, but the operating system, applications, and all system settings. Cloning your computer is most beneficial when downtime is a major concern. If you are running just a full or incremental backup and your hard drive crashes, you have to install a new hard drive, install the operating system and restore your data from the backup. Eventually, you will have all your data backup, but depending on the time it takes to get a new hard drive and the amount of data to restore, it can take a day or more to get your computer fully operational again. With a clone backup, you can simply reboot the computer from the clone drive and immediately start working again on your computer like nothing ever happened. Companies who rely heavily on certain computers find it helpful to have them cloned.
The problem with clones is that your backup will only have data up until the last time the computer was cloned. If you clone your computer every night and your computer crashes at 4 PM in the afternoon, you will have lost any data that you changed or added during the day. A clone also does not keep any historical data. You only get exactly what the hard drive looked like when the clone was run. You cannot go back in time and look or earlier versions or previously deleted files. Because of these limitations we recommend that clones be used in addition to, not in place of, full or incremental backups.
Now you have a basic understanding of the three types of backups. Next time we will look at different types of backup programs and which one(s) would be right for you.
Full backups are complete copies of the data you want to back up. For example, if you wanted to make a full backup of your documents folder you could simply select your documents folder and drag and drop it onto an external hard drive. Your Mac would create an exact copy of everything your documents folder on the external drive.
Full backups can easily be created manually by dragging and dropping the files and folders you would like to back up. The problem with manual backups is that people forget to do them. Invariably, when you need to back up you realize that a backup has not been done anytime in the near past. We recommend using software to automate the backup process regardless of what type of backup you are doing. Backup software helps to ensure the backups run according to schedule and organizes the backed up data.
Incremental backups can only be done with backup software. The first time an incremental backup runs it creates a full backup. The second time an incremental backup runs it only looks for files that have been changed or created since the first backup. It then adds only those files to the backup. Incremental backups are valuable for a few reasons.
One, they take up less space than full backups. Since only the data that has changed since the last backup is backed up, subsequent backups after the initial backup are much smaller. This allows you to store more backups on your destination device.
Two, incremental backups allow you to go back in time and see multiple variations of a file and find files that may have been deleted at some time in the past. An incremental backup builds a history of activity on your computer that can be accessed as needed at a later date.
Three, since the backup does not have to back up all data every time the time it takes to run the backup is significantly less than a full backup. You can then run these backups more frequently. It’s not uncommon to run incremental backups once an hour.
The third type of backup is a clone backup. Clones also require special software to run. A clone is an identical copy of everything on your hard drive. This includes not only your user data, but the operating system, applications, and all system settings. Cloning your computer is most beneficial when downtime is a major concern. If you are running just a full or incremental backup and your hard drive crashes, you have to install a new hard drive, install the operating system and restore your data from the backup. Eventually, you will have all your data backup, but depending on the time it takes to get a new hard drive and the amount of data to restore, it can take a day or more to get your computer fully operational again. With a clone backup, you can simply reboot the computer from the clone drive and immediately start working again on your computer like nothing ever happened. Companies who rely heavily on certain computers find it helpful to have them cloned.
The problem with clones is that your backup will only have data up until the last time the computer was cloned. If you clone your computer every night and your computer crashes at 4 PM in the afternoon, you will have lost any data that you changed or added during the day. A clone also does not keep any historical data. You only get exactly what the hard drive looked like when the clone was run. You cannot go back in time and look or earlier versions or previously deleted files. Because of these limitations we recommend that clones be used in addition to, not in place of, full or incremental backups.
Now you have a basic understanding of the three types of backups. Next time we will look at different types of backup programs and which one(s) would be right for you.