WAN Backups - Innovation for an Oldfangled Technology

By Beth Cohen | Nov 17, 2003 | Print this Page
http://www.enterprisenetworkingplanet.com/netsysm/article.php/3109801/WAN-Backups--Innovation-for-an-Oldfangled-Technology.htm

Are you still backing up your systems the old-fashioned way – on tape? Have you been mirroring server disks and dutifully dropping tapes into the stacker year after year, only to see your company grow to 10 offices in five states with a recently opened outsourced branch in, say, Bangalore? And now your boss has just told you that you need to incorporate the new systems into the backup scheme, but your backup capacity is already maxed out. Before you look at buying yet another tape stacker, it’s time to consider an easier, cheaper way to back up your systems.

Or consider another example — as the owner of an engineering firm with offices worldwide, your engineers need to work on complex CAD designs from many different office locations simultaneously. As business becomes increasingly collaborative, your users must share files across the Internet or on your company WAN. Think of the improved efficiency if all your users could share the latest data files by using technology that delivers continuous synchronization and file system distribution over the Internet.

Face it, backup tape systems are old technology; they have been around since the beginning. Still, while backup can be boring, costly, and time consuming, ignore it and you jeopardize your entire enterprise. Fortunately, though, as the cost of disk storage has fallen to commodity levels and connectivity costs have plummeted, better methods for solving your backup problems have emerged. Today we will look at several network alternatives to the old-fashioned drudgery of tape backups.

WAN Backup Systems

The problem faced by many companies in the wired age is that the staff and their computers are no longer located at a single headquarters where the data on the mainframe servers can be conveniently backed up nightly while most people are sleeping. Data is scattered across the network, and people are working from just about anywhere and at anytime. Since the data is not coming back into the central data center anytime soon, backups must be designed to go out to where it does reside — on mobile systems, remote office servers, wherever.

Many years ago there was an apocryphal story going around the net about systems administrators who were using the old Usenet newsgroups as a form of cheap universal system backup. They would create fake newsgroups in the .alt area and populate them with their files. Since it might take weeks for the top-level server administrators to notice, the files were safely backed up on several high availability servers and could be downloaded or restored to any system that had Usenet access. Admittedly, there where some minor security and legal issues with this practice, but conceptually, they were on the right track.

Although the heyday of the Usenet newsgroups is long gone, the concept of file backup using other people’s high availability resources is not far from what those maverick admins were doing. Only now, it’s not only legal, but also encouraged — for a fee, of course. Using in-house installed software or a monthly Internet backup service, companies can back up their distributed systems for a fraction of the hassle and cost associated with the old methods.

Increasingly, companies are “solving the problem of storage access by removing the need for users to use a VPN solution or to connect to one of the central servers to access their files,” says Ellen Ohlenbusch, Sr. VP & Co-Founder, Availl, Inc. in Andover, MA., a vendor of distributed data mirroring and storage software. Her company’s flagship product, Availl 2.6, is a unique distributed replication solution for companies that need to share large data files between remote offices and scattered servers. “One customer is using Availl to synchronize complex CAD assembly files across their organization from engineering located on one coast and manufacturing offshore. This was something they had never been able to do before.”

Page 2: How WAN Backup Works

How WAN Backup Works

WAN backup software and systems take one of two basic approaches to solving backup problems. Either they copy your staff’s key data files to a centralized backup server (your company’s server or a service provider’s system) only when the systems are actually network connected, or alternatively, they continuously replicate file system information between distributed systems. Both methods are effective, but each has slightly different requirements and implications.

A network server backup is commonly implemented with a mobile work force that might only be connected an hour or so a day. Normally the user will be prompted to perform a backup before they logoff. The advantage with this method is that it’s very flexible about the number of systems that can be supported. However, the disadvantage is that the user might either rarely connect or skip the backup due to the time it takes, leaving them and the company vulnerable to unexpected and unacceptable data loss.

The other network backup system only copies the pieces of the files or bits that are different. Think of it as applying old database replication notions to a standard file system. These backup applications solve the old database problem of backing up always-open files.

The same methodology used to minimize bandwidth in streaming videos, video conferencing, and large database systems is applied to backup technology. As Ohlenbusch puts it, “By using byte-level differencing technology, Availl's flexible mirroring technology instantly replicates files (one way or bi-directionally) in real-time, to or between any numbers of systems."

Because Availl 2.6 only transports the differences between the files, not the entire files, it minimizes the network load of the replication process. Perfect for files that change constantly, large numbers of files, extremely large files, application files (web servers, databases, etc), data for remote offices, disaster recovery needs, CAD files, or data that needs to span any number of servers located anywhere, the byte-level differencing technology transparently results in 95% bandwidth reduction, with files always continuing to be useable.

Outsourced Backup Service or In-House System?

So, which type of approach will work best for your business? The choice is dependent on the specific needs of your company. If you have many mobile users who are only dialing up or accessing the network an hour or so a day to check their email, but who are not performing much synchronous file sharing, you are probably better off with an Internet-based backup service or a centralized backup server.

The outsourced service cost is normally based on a monthly charge per system, and it offers the maximum flexibility as your backup needs change. If the economics work for you because you already have substantial investment in a data center and staff, you have the option of installing and maintaining such a system in-house as well.

If you have a number of fixed remote offices with local servers, then using a distributed product like Availl’s is a logical solution. With the added complexity of users commonly sharing complex data files and a need for integral disaster recovery, a distributed WAN backup system has many advantages. Of course, you will need to install and maintain it in-house, as this service is not currently available as an outsourced option.

Conclusion

If you have multiple remote sites or users and you are sharing distributed data, you owe it to yourself to be looking at this technology. Whether you decide to host a remote solution in-house or use a remote backup service provider, you should seriously consider distributed data mirroring and storage software that allows you to back up your systems and synchronize your files across multiple locations. The bottom line is that unless you have a real need to hold on to those stackers and you love the smell of backup tapes, it might be time to retire them and move up to the next generation of backup technology.

Additional Resources

www.availl.com – Availl Inc. Website
remote-backup.com – Vender of remote backup software to service providers
http://www.snia.org/tech_activities/workgroups/backup – Storage Networking Industry Association's Backup Workgroup


Beth Cohen is president of Luth Computer Specialists, Inc., a consulting practice specializing in IT infrastructure for smaller companies. She has been in the trenches supporting company IT infrastructure for over 20 years in a number of different fields including architecture, construction, engineering, software, telecommunications, and research. She is currently consulting, teaching college IT courses, and writing books about IT for the small enterprise and wireless network security.

» See All Articles by Columnist Beth Cohen