Cloud backup options: Pure cloud vs hybrid cloud backup

Cloud backup is increasingly being seen as a flexible and cost-effective option by many organisations, but what are the pros and cons of pure cloud backup and hybrid cloud backup?

Cloud backup continues to make inroads in corporate data centres. Almost a third of IT organisations are backing up at least some of their data to the cloud, according to Storage magazine's spring 2012 Storage Purchasing Intentions survey. And a global TechTarget survey found late last year that about one-fifth of IT shops in Europe are planning to deploy cloud backup or cloud storage in 2012. In this article we look at the options for organisations looking to use the cloud for backup.

In short there are two main cloud backup options: pure cloud backup and hybrid cloud backup.

In contrast with traditional backup, in which an organisation backs up to locally available storage, cloud backup is all about sending copies off-site to a cloud provider. How you do that is where the distinction between the various cloud backup options arises.

With pure cloud backup, data is copied directly to the service provider's cloud. With hybrid cloud backup, on the other hand, data is copied to a device with installed storage that resides between your infrastructure and the cloud. The hybrid cloud device provides the advantage of retaining data locally to smooth out transport to the cloud and in case restores are needed.

A further nuance in the cloud backup scene is that you can often use mainstream backup apps, as many now have the option to back up to the cloud.

Pure cloud backup

With pure cloud backup, agents are installed on machines, with backups going directly to the service provider's cloud. The key benefit of a pure cloud approach is that it is easy to implement, scalable and very well suited to organisations that don't possess in-house IT department skills.

The costs of these services go up or down depending on use and allow organisations the ability to accurately model their backup costs in line with projected backup data set growth. This can remove the almost-impossible task of attempting to factor in the full costs of local backup storage in IT budget projections.

In contrast with traditional backup, cloud backup is all about sending copies off-site to a cloud provider.

Pure cloud backup services promise to remove the daily grind from backup administration, with a "fire and forget" approach following initial installation and then seamless background integration with the cloud, as well as portal-based administration.

The key drawbacks with pure cloud are that it is very much restricted by available bandwidth. So, it's not an approach suited to organisations with large and complex backup requirements that would hog Internet connections. Likewise, if you're likely to need restores of large files that would take a long time to download, pure cloud will not be for you.

For pure cloud, you can use service providers that have their own infrastructure, such as the Evault Online backup service, the Iron Mountain LiveVault service or one of numerous service providers that use Asigra's cloud services.

Hybrid cloud backup

For organisations that produce a fair amount of data and have a requirement for easily accessible restore operations, cloud backup vendors have implemented a hybrid approach.

This cloud backup option consists of an on-site NAS appliance that acts as a local backup target and then performs background synchronisations of backup data sets to an external cloud. When a restore is required from a recent backup, the data is sitting ready on-site in the NAS and can be quickly accessed. Alternately, restores from external cloud-based backup sets can be recalled from the cloud into hybrid NAS on-site storage on demand and restored from there.

Some examples of vendors offering this type of service include Barracuda Networks with its hybrid backup appliance range, which can include as much as 12 TB of on-site storage and multiple off-site synchronisation services. Simpaticorp offers the DR range of NAS backup appliances with the DR4 enterprise model also supplying as much as 12 TB of storage and synched to a dedicated cloud. Ctera also has a cloud-attached storage solution, the C800, with 12 TB of available storage.

Backup software cloud options

Mainstream backup software vendors now include cloud backup options built into their software suites, providing for cloud as a backup target either directly or via a hybrid backup appliance.

Such features often allow users' backup streams to be encrypted as they pass through public networks, and backup data is then managed via Web portal or the backup software when restores are required. As these services are fully based on Web-enabled technologies, it is now possible to back up from and restore to registered mobile devices from any location worldwide with sufficient Internet connectivity.

Vendors offering this approach include Symantec with its Backup Exec.cloud service, which features integration with the Nirvanix cloud service. CommVault offers cloud as a target in its Simpana backup suite, with a choice of cloud providers including Amazon, Microsoft and Nirvanix.

Backup solutions of this type offer a multi-tiered approach to cloud backup with options to implement private, hybrid and public cloud-based approaches.

Martin Taylor is converged network manager at the Royal Horticultural Society.

Next Steps

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