Definitions and Differences
Backups: A backup is simply a snapshot of your virtual machine, typically taken once a day. Backups are usually:
- Automatically configured to happen daily, after close of business
- Stored for a period of time, with a retention policy like “one a day for a month and one a month for a year”
- Kept in a place separate from the primary system, like a basement, another data center, the back of a Honda, or, in the case of Backup-as-a-Service, in the cloud.
- The last copy you have is last-night, which is usually stale. Most business applications change a lot during a day.
- To re-awaken a system from a backup takes time. First, you need a ready-and-working system, rebooted and happy – and then you have to mount the backup. The whole process isn’t speedy. If the backup is (more safely) stored elsewhere, there’s the travel-time of getting it to the primary location, as well.
- Replication periods are measured in minutes, or even seconds. So, the last copy is fairly fresh.
- The secondary copy is held in stasis (like a ghost, or horcrux, for the Harry Potter fans) until it is re-animated via a fail-over trigger
- The secondary location can be another data center in another region, or even the cloud, in the case of DRaaS.
Disaster Recovery-as-a-Service (DRaaS): If you don’t have access to a secondary location – or don’t want to pay for it – DRaaS enables you to execute the same Disaster Recovery replication with the cloud as your secondary location. In that case:
- The speeds involved are similarly fast: minutes or seconds to recovering systems
- You pay only for storage while the systems are replicating/in stasis – and once they fail over, you’ll pay for CPU and Memory resources, as you consume them
- You will want to vet the cloud as an operating environment for your workloads – meaning, it better be secure, have excellent customer service, etc.
If you have any questions, please contact us. We’ll be happy to help.