If I can take a snapshot of my system, why do I need backup? Or if I already have backup, why do you want me to archive? Well these 3 terms can easily be interchanged but today, we are going to look at the real difference and how each one of them can be a benefit to your organization.
A snapshot is a frozen-in-time version of your system (VM or volume) that you can go back to or leverage (clone from snapshot). It is as if you had a copy of the hibernation of your machine and you can go back exactly to that point. After taking a snapshot, the differential data is saved separately creating a three.
The particularity of snapshots is that it is saved in the same location as the live system and it relies 100% of the availability of the original components that make it. Simply put, if you lose some of the original files, the snapshot is useless.
So, what’s the point? Well snapshots are a great way to save a working state before testing or performing some change on a live system. They are quick and easy to use (almost instant restore). Besides it comes embedded and licensed as part of your hypervisor or storage system.
This is usually the term used to define everything that is a point-in-time copy. At the simplest level, a backup is a copy of your system, that is hopefully stored at an external location.
A backup does not depend on the original data and can be used to restore the data (VM or Volume) to an earlier state. A backup can have multiple restore points, allowing you to restore to different dates or time.
The particularity is that we take a backup of data that is still live or that we still access in order to restore it when an event occur (error, corruption, disaster, etc.)
This is where the fun happens. What is the difference between backup and archiving? We will get to that shortly.
An archive is a point-in-time copy of your system taken to be kept for an extended period of time. An archive is kept for 3 years, 5 years, or even more depending on the retention policies of the country or industry you find yourself in.
The particularity is that once you archive something, the original data is deleted from the source. This means that once something has been properly archived, you cannot find it in the live system anymore. If you require to have access to it, you need to follow the procedure in place to access archive. It is recommended to seal archives and make them WORM (write-once, read many).
That’s it! You now know the difference between snapshot (copy of live system that depends on the original data), backup (copy of system that is kept externally) and archive (copy of data that is no more in use). A good data management strategy must include a combination of these components.
You must take snapshots whenever a minor or major change is going to happen to the system. It is the fastest way to go back in time. You must take periodic backup and follow the 3-2-1 rule to never lose your data when a disaster occurs. And you must keep data archives that are sealed for long retention and compliance.