Remind me, what is 3-2-1 backup?
The 3-2-1 backup rule means that you should have 3 independent copies of your data – 2 of which are stored on-site for fast restore and 1 is stored off-site for recovery after a site disaster. There are many different ways to create this system, particularly when looking at the on-site options. It’s also worth noting that distinction between replica ‘ready-to-run’ copies and more traditional backup copies is becoming less and less clear, and the terms backup and replication are often used interchangeably.
Backup vs. replication
The onsite copy of your data can be a backup copy or a replica of the server you are protecting. The difference between backup and replication is that backup refers to copying files (or data blocks) to some external media, while replication is the creation and synchronization of an exact copy of the server in the native server format.
A replica is ideal for direct spin-up, while a backup copy usually requires a restore process before it can spin-up. A major benefit of having a backup copy is it typically contains multiple restore points in time. You can go back to the state of the data one week ago or one month ago, for example.
Designing your 3-2-1 backup combination
At Leaseweb, there are a number of ready-to-use products which can be used to create a 3-2-1 backup of your server and data. See some examples combinations below.
|IaaS||Onsite original data||Onsite copy||Offsite copy|
|Virtual Server||Virtual Server||Acronis Cloud Backup|
|Dedicated Server||Dedicated Server||other Dedicated Server||Acronis Cloud Backup|
|Private Cloud Apache Cloudstack||Private Cloud Instance||Acronis Cloud Backup|
|Private Cloud VMware vCloud||Private Cloud VM||Veeam Backup||Acronis Cloud Backup|
|Private Cloud VMware vSphere (single tenant)||Private Cloud VM||Veeam Backup||Acronis Cloud Backup|
For the original data storage, the infrastructure services are already equipped with redundant storage platforms that have high availability features. Dedicated Servers are typically ordered and delivered with multiple disks in a redundant RAID5/6 setup to protect against disk failure (failed disk hardware replacement included).
For storing an onsite copy, a Dedicated Server can easily be setup with Private Networking to connect with a Dedicated ‘Backup Storage’ Server. You can choose any available OS feature (or run a software application of your choice) to manage the replication of the data. Examples are Linux DRBD (automatically replicates all data) and Linux rsync (manual file-based replication). For Leaseweb VMware platforms only, Leaseweb offers Veeam Backup which currently functions as a solution for onsite backup. This service does not require a software agent and comes with a self-service management portal.
The offsite backup protects against a complete site disaster. Some backup providers give the option to test (or even run) the off-site backup copy directly within the offsite cloud environment, without the need to restore first to your onsite server infrastructure.
The offsite copy solution is offered as an add-on self-service. This service is powered by the Acronis Cloud Backup software agent and a self-service management portal.
Note, for advanced setups, some enterprise customers enable both fast restore and site disaster recovery in one through a twin data center setup, whereby an offsite/twin data center replica enables both fast restore and site disaster recovery.
As you can see from the table above there are various ways to design a 3-2-1 backup using Dedicated Servers and Cloud services. Some companies employ an even more expansive backup strategy, using more than one off-site backup partner to create a 3-2-2 setup for example. There is no such thing as a perfect backup system but diversifying and having different options is only going to improve your chances of a smooth recovery from a disaster.