There are critical differences in cloud storage according to backup size and priority. SMB – including education and small government agencies – primarily require acceptable backup and restore performance plus security and compliance reporting. The enterprise needs these things plus additional solutions for backing up larger data sets across multiple remote sites and/or storage systems and applications.
Note that no one is talking about backing up the corporate data center’s petabyte-sized storage to the cloud, not yet anyway. At its present level of development, online backup is best done for smaller scale systems. But even with this limited approach, it can have real advantages for business backup.
Cloud storage is not a do-all and be-all of data protection but it does have real benefits for some environments. One of its biggest advantages is replacing extensive off-site tape vaults. Tape libraries for active archives and massive on-site backup can be quite valuable in big data environments. But traditional off-site vaults require users to change tapes, label them, track usage, and order the truck to take them to the off-site vault; then go through another multi-step process to recover the tapes. In this respect online backup is far easier and less prone to manual error.
Other advantages include unlimited data retention – you are not bound by the size of on-site data centers and storage systems. This does not mean that you should practice unlimited data retention but you can certainly grow your backup storage quite easily.
Cost-effectiveness is an advantage when it happens, but cloud backup does not equal cost-effective. More on this later.
Disadvantages of Cloud Storage
Despite the marketing hype, there are clear disadvantages to cloud storage. WAN bandwidth can be significantly slower than backing up to disk and even to tape. This should not be too bad for backup once the initial upload is accomplished, but it can significantly affect restore times. This is why a lot of companies write in their SLAs that if remote data cannot restore over the pipeline with the Recovery Time Objective (RTO), the provider will ship the data on removable media. Low tech but necessary in these cases. Privacy and security are additional concerns. Never assume that your data is kept private from the service provider employees. For this reason many providers offer at-rest encryption for backup data as well as in-transit.
Vendor lock-in and failed service provider businesses are another issue. Many online backup service providers operate on razor-thin profit margins. When you are looking at providers, be certain that you will have guaranteed and easy access to your backup data should the company go out of business or be acquired.
Selecting a Cloud Storage Vendor
Critical features include acceptable-to-you backup and restore performance, security, and cost-effectiveness. Good ideas depending on your needs include compliance monitoring, granular restore, protection against vendor lock-in, cached backup and continuous backup options.
Backup and Restore Speeds
A primary concern with cloud storage is acceptable backup and recovery speeds. Look for the following features: dedupe and compression before sending, WAN accelerators, and fast ingestion on the cloud side, often from solid state drives and/or caching at the storage controller.
Data dedupe and compression are absolutely critical to accelerating the WAN. Dedupe and compression need to occur on-site on the backed up data before sending it over the pipeline. The cloud service should send back the data in the same compressed condition for faster restores. Once the baseline upload is done, sending changes-only backup through the pipeline also helps to accelerate the WAN. Networking throttling can help with some workloads, as can biting the bullet and investing in fatter pipes. Scheduling backups for idle network times is also a time-honored performance idea.
Also consider granular restore options for restoring files or folders, not entire volumes. Closer physical distance between the provider’s data center and your backup site also helps to diminish latency around restores. Some online providers offer multiple geographical locations for data backup storage for this reason.
Standards universally require encrypting the backup data stream. There are additional requirements depending on the standard including highly secure user access control, physical and digital security of the provider’s data center, and specific encryption schemes depending on the compliance and governance requirements.
When researching service providers look for data center certifications like Tier-4 SAS 70 and review the SP’s digital and physical security. And in addition to encrypting in-transit data, encrypting at rest is common for sensitive data in multi-tenant environments.
Access control is another critical security measure. User access controls need to be in place both from the corporate site and on the provider site. Anyone who has the opportunity to reach your data needs to have their access controlled. Ask if the provider carefully screens their employees and tracks their activities while at work.
Even though a major marketing point for cloud storage is low price, it is not a given. Prices are often low for the most basic of backup services – simply storing massive data in the cloud without having to restore it often. (Or ever.)
And the cloud does offer real savings past a low price: if you are running out of data center or closet real estate the cloud is an excellent choice. You can also save significant employee labor costs by dispensing with tape cycling and storage system management. But the more data you add, the higher the cloud storage cost grows, and a one-to-one comparison between the per-GB cost of online backup and buying local disk is not in the cloud’s favor.
Also observe good data retention policies. “Save everything” is not a good plan when it comes to economical backup storage – no matter what platform you choose.
Is Cloud Storage Worth It?
Is online backup worth it for business? Yes, absolutely – if you match the online backup features to your data backup priorities. Do not treat your backup as one-size-fits-all.
Tier 1 applications with critical restore needs are best kept on-premise and replicated to DR sites. Online backup is primarily applicable to Tier 2 backup: it must be recoverable but a 2-24-hour recovery period is acceptable. If the online backup vendor offers granular recovery this is even better.
Know your backup needs, know online backup’s advantages and disadvantages, and carry out your due diligence. It’s the start of a beautiful friendship.