Linux backup script

A dangerous money Waster: The hidden costs and security risks of in-house backup programs can endanger data security and the bottom line - Internet

For quite a few years now I have worked extensively with members of the international Linux community, primarily networking professionals who are looking for methods to optimize backup while maintaining a high degree of security. From Europe to the United States to the Far East, there is a common mindset reflecting the freedom of open-source solutions. The dedication to the open-source concept, the willingness to share advances in operating systems, has of course led to widespread advancements in software.

But there are times when it seems that such enthusiasm for an idea can get in the way of considering other reasonable alternatives. I often encounter this when speaking with people about commercial backup software. Recently, while visiting a potential customer with a large, complex, heterogeneous system, it was somewhat astonishing to hear that they were primarily using tar-based homemade scripts to perform intricate network backups. Their main justification was the cost of commercial software.

With a little bit of analysis, it is possible to see clearly that "cost" is a relative issue and that it is not the only important factor related to "homemade" backup software.

Based on experiences and conversations with dozens of system admins, it's my contention that in-house scripts or programs are:

* Comparatively expensive

* Poor performers

* Dangerous to use in commercial activities

Network backup software is much more complex than it sometimes appears. The mission of backup software looks quite simple: Take a copy of data from a computer and write it onto a storage device. Although easy to say, this operation is considerably more difficult to accomplish reliably and consistently. A network backup must deal with every individual aspect of computing such as file systems, CPU architecture, OS, access rights, network protocol, SCSI chain, tape and library management and more. Each layer is complex to master as a standalone topic, and interoperability between all of them requires the most proficient development skills available in this industry.

The basic Linux tools look OK to do the job, but they aren't. A tar-based program using NFS for network capability is a widely used utility developed by system admins. But it suffers from numerous flaws that sometimes make it useless. Common defects can include restrictions like:

* One tape for one backup for one machine

* No catalog of backed-up data, i.e., the entire tape must be restored to retrieve an individual file

* Questionable reliability

Conclusion: This sort of program should be reserved for occasional and very limited needs.

Although writing software is fun, it doesn't make much sense from a budget point of view. Simple cost analysis shows that in-house software is too expensive.

Compiling a simple tar-based script for one machine that writes to a local tape should take no more than a day. But, then you must do some testing, improve tape management, refine the data selected for backup, do some more testing, etc. You can easily spend a week on this. Then you expand the solution to several other machines and do some more testing. Finally, after a couple of weeks of refining the process in your spare time, you probably have something useful. Everyone pats you on the back for this achievement. And of course, you must write an extensive description of your work, the procedures to follow for backup, restores and troubleshooting.

Follow-up is not very convenient, either: loading a new tape for each machine, making sure that the script will work as designed. That's an easy 15 minutes per machine per day, maybe an hour for only four machines. And once a month, on average, you will need to analyze/modify/adapt your script to follow the evolution of the machines to be backed up. This can easily take another half a day per machine.

The math is simple. Basic script design, pre-install testing, followed by regular tape changes, then modifying the script to reflect changes in the network... two or three hours a week become 20 or more a month, a couple of hundred hours per year.

Considering an average salary of $50,000-$60,000 per year for an experienced network professional, these non-productive hours add up quickly. By the end of the year, the in-house tar-based "cheap" solution is costing the company thousands of dollars just in workmanship. And this is a recurring cost, in addition to the money that will be spent trying to analyze and fix features that almost work.

Where is the logic of a recurrent, unnecessary annual expense for software that almost surely does not do the job adequately? The only advantage over commercial software is that homemade software is pain-free in terms of issuing a PO and spending the IT budget. The company actually spends the money, but it is buried in the IT salaries. No one sees it, an invisible expense that eats into company profits.

A better solution is obviously proven, dependable backup software with a tape-library. Purchasing and installing reliable backup (hardware and software) is much less than the "true" potential cost of handcrafted software. And total cost of ownership (TCO) will be a very small percentage of the TCO of a homemade, meticulously written software. The cost/performance ratio leans even more heavily toward commercial software when you consider benefits like technical support by network engineers and the possibility of automatic software updates.

In-house software just cannot meet enterprise requirements since backups are performed to protect the company's assets. A business can't afford to be in jeopardy just because its data has not been backed up by a rock-solid program.

Operating systems, databases and hardware are in a constant state of evolution. Backup software has been continuously improved over the last few years. Development teams at Arkeia and other companies are serious about improving reliability, increasing backup speed and incorporating the latest technologies and operating systems. Competitive survival makes this attitude an absolute necessity. It is virtually impossible for in-house software to even approach the level of quality of meticulously developed commercial software. And your company expects this level of quality.

The Security Issue

In-house software is potentially dangerous for the company. First, the capability of a homemade solution to restore precious data in a timely manner is very questionable. But this is not the sole danger of such program. An in-house program written by a sys-admin acting independently is by itself a breach in security. What happens when your sys-admin goes on vacation? Is there anyone else who can use the tool? Other than him, who can restore your data if there is a disaster? If the author of the program leaves the company, is there anyone able to maintain and revise it? Is your backup system vulnerable?

Misuse of Top-Notch Personnel

Another very real consideration is the misuse of competent personnel. When a company has a system-admin good enough to design and develop a really sophisticated backup solution, this automatically implies that the person is an extremely valuable asset for the company. Having him/her monitor unnecessary tasks like changing tapes and manipulating scripts is a waste of time and money. The system-admin is taken away from valuable time that he/she could utilize to study, test and implement newer and more efficient technologies. This conceivably could cause the company to lose competitiveness.

With a commercial product like Arkeia, only a quick orientation is required for non-technical staff person to monitor and modify backups through a user-friendly GUI, saving your specialists for the real work needed in today's constantly evolving technologies.

Conclusion: The question is not whether you can afford commercial backup software, but whether you can afford not to have it. Choosing the option of a homemade design can cost your company time, extra money, competent human resources and competitiveness. A competitor who chooses a commercial solution can have a turnkey package for much less actual expense while keeping company energy intact for refining critical systems and pursuing business.

Phil Roussel is CEO of Arkeia (Carlsbad, Calif.)