Storage replication has often been suggested as an excellent methodology for data protection. However, SMBs often have a hard time deciding which type of data storage replication is best for
Before implementing storage replication, SMBs must first establish their individual data protection requirements. This means determining what types of data loss protection is wanted, needed and/or required, as well as the amount of budget that can be spent. Data loss can be the result of a hard disk drive failure, a storage system failure, a user error, an application error, data corruption, malware, a building or campus disaster, or a regional disaster. Establishing data loss protection and recovery requirements narrows down the potential data replication choices and simplifies selection. For example: If the requirements include rollback protection against human error, corruptions or malware, mirroring is not a good choice. The replication option must include time-based versioning to allow for rollback.
The three types of replication technology that makes good financial sense for a cost-conscious SMB are server-based, storage system-based and cloud-based backup or replication service (i.e., online backup).
Server-based options are basically software that runs on the server and replicates server-to-server (like-to-like) locally or over the wide area. Some of the common data replication options in the server-based category include CA XOsoft, CommVault Simpana, Double-Take Software Inc., EMC Corp.'s RepliStor, InMage Scout and Vizioncore vReplicator (VMware VM replication only). For Windows-only environments, Microsoft Corp.'s Distributed File System (DFS) replicator is a very effective form of low-cost replication. Note that some logical volume managers such as Symantec Corp.'s Veritas LVM, SUN ZFS, some of the Linux Inc. LVMS, and most of the Unix LVMs also provide various levels of server-based replication. All of these options can provide cost-effective data protection replication if they meet your requirements.
Storage system-based replication
The storage system-based replication options are far more numerous. The vast majority of storage systems today provide some form of replication. Storage system replication typically includes snapshots and mirroring (sync, async, and/or semi-sync which is snapshot mirrored async.) Some even provide continuous data protection (CDP). A good way to think about CDP is that it's functionally similar to snapshots on every single point-in-time, allowing rollback to any data version. Storage system-based replication is available through most arrays. However, storage system replication functionality and pricing varies. Make sure any vendor(s) selected are tested to insure they meet your requirements.
Cloud-based backup and replication for SMBs
The cloud-based backup and replication option is interesting and usually quite simple to implement. It provides an on-site appliance and/or software agent(s) for your servers or applications. Data is then replicated to the cloud service provider, and along the way it's usually incrementally replicated, deduplicated, compressed and encrypted. Costs are predictable and tied directly to the amount of data stored and the service requirements for data recovery. The key is the data recovery requirements. Most cloud services can handle files and relatively small amounts of data recovery over the WAN. Large failures or real disasters are another matter. This type of data recovery requires special handling by the cloud service provider. The WAN bandwidth is commonly too slow to provide any form of useful timely recovery. Usually it means providing a storage system with your data overnighted to your facility of choice with onsite support. The difference in pricing reflects the type of data loss recovery you require.
There are literally thousands of cloud-based service providers. But here is a representative sample: Arcplace, Axcient Inc., Backup My Info Inc., Bell Canada, CDW Corp., EVS Corp., DS3 DataVaulting, HexiSTOR Data Protection Services, Hewlett Packard (HP) Co., IBM, Remote Backup Systems, Renovo Data, RestorePoint Inc., SpiderOak Inc., SunGard Secure2Disk, TDG Communication Inc.'s Dakota Backup, Technology Partners, Venyu Inc.'s AmeriVault, XiloCore and many more.
There are numerous low-cost replication choices for SMBs, but picking the right one means spending meaningful research time up front.
About the author: Marc Staimer is the founder, senior analyst, and CDS of Dragon Slayer Consulting in Beaverton, OR. The consulting practice of 11-plus years has focused in the areas of strategic planning, product development, and market development. With over 28 years of marketing, sales and business experience in infrastructure, storage, server, software and virtualization, he's considered one of the industry's leading experts. Marc can be reached at firstname.lastname@example.org.
This was first published in November 2009