Tomasz Zajda - Fotolia
There are many use cases for storage snapshot technology. But the most important thing to remember is that while many backup applications leverage snapshots as a way of enabling features such as instant recovery, a snapshot is not a standalone backup replacement.
By submitting your personal information, you agree that TechTarget and its partners may contact you regarding relevant content, products and special offers.
Storage snapshot advantages
Snapshots are best suited to the task of virtual machine rollbacks for infrastructure servers or offline application servers. This might sound a lot like a point-in-time recovery, but the processes are quite different, as are the implications of using storage snapshots versus performing a standard recovery.
A snapshot does not create a copy of your data; instead, it results in the creation of a differencing disk. This differencing disk has a parent-child relationship to the original data source and intercepts all future write operations. This leaves the original data source in an untouched state. Performing a point-in-time recovery using snapshot technology involves removing one or more differencing disks so the system can be returned to a previous state. This is in sharp contrast to a traditional data restoration that handles point-in-time recovery by copying data from a backup.
A storage snapshot's reliance on differencing disks makes snapshots well-suited for some types of rollbacks, but not others. For example, if you wanted to protect yourself prior to applying a service pack to an infrastructure server, snapshots would be an ideal way to do this. The snapshot can be created instantly, and without taking the system offline. If something were to go wrong during the service pack installation process, the system could be reverted to a previous state by applying snapshot technology.
Storage snapshot drawbacks
Conversely, snapshot technology is often a poor choice for protecting application servers unless a snapshot is made while the server -- typically a virtual machine -- is offline. Storage snapshots preserve the state of the server's storage as it existed at a particular point in time, but many snapshot offerings do not capture memory state, which is critical to an application server. Finally, most storage snapshot products are not application-aware, although the Hyper-V 2016 checkpoint feature (the snapshot mechanism for Hyper-V) will include application awareness.
How to overcome the inherent weakness of snapshots
Create snapshots of VMs, not LUNs
Snapshot value relies on clean copy of data
Dig Deeper on Backup for virtual servers
Related Q&A from Brien Posey
Social network backup tools are hard to find, but they are out there. Like with file data, your organization should make sure its social media data ...continue reading
The idea of chargebacks is to help organizations use private cloud resources efficiently by making departments pay for what they use, but the ...continue reading
Microsoft Word may be the go-to application for word processing, but there are solid alternatives that organizations can turn to instead.continue reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.