Capacity Planning

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Once you have designed (or inherited) your backup architecture, experienced a successful rollout, and had an opportunity to monitor the activity, performance, and usage, eventually it will be time to address growth and expansion. Naturally, the best way to address growth is to anticipate through capacity planning; however, most find themselves in the middle of expansion without the lifeboat of preplanning at their disposal. As a result, many of the decisions being made are reactive, based on the person or groups that happen to be, figuratively speaking, threatening the most bodily harm.

In this chapter, we give you the information you need about expanding your backup environment to make your life as a storage administrator as easy as possible. The backup tool you selected for your environment will dictate the practical application of what we will be discussing in this chapter. For purposes of illustration, VERITAS NetBackup is used in most of the examples, but when possible, a more generic approach for capacity planning is used.

React versus Respond

Time is slipping away. Yes, in most environments the amount of time we are given for backup is shrinking. Neither of us has ever been at a client site where we were told that we have been given another three hours for the backup window; that just doesn't happen-at least in our experience. Not only is time slipping away from us, but the data continues to grow, sometimes at an alarming rate. Once, a pristine backup environment would successfully complete every job before the window closed. Now we are struggling to get all jobs done within the window. For the unprepared storage administrator, this happens very slowly, almost unnoticed, until one day you are faced with a report full of failures and begin to react as opposed to respond to managers, administrators, and users who are at your desk looking for their data to be restored. We will try to illustrate this contrast in the next paragraph, but suffice it to say that we are less likely to be productive when we react as opposed to being able to properly respond. We want to move away from a reactive posture to a responsive posture as storage administrators. When we react we tend to occasionally lose our temper and make irrational decisions. Conversely, with a responsive posture, we tend to start with a goal in mind, and our moves are planned and intentional. This means we need to plan for the eventual growth of our environment, again putting the onus on the people who control the budgets so they too may take a responsive posture within their own job responsibilities.

It's human nature to react when you feel you are being attacked. Within that context we do one of two things: fight or flee. This concept has been around for a long time. In disaster recovery (DR) presentations, the presenter will normally ask how many in the audience actually have a DR plan. Inevitably someone speaks up and says, 'Yeah, it's my updated résumé'- in other words, a flee response. Then there are the shouting matches surely you have witnessed between a storage administrator and a business unit manager when data was lost and couldn't be restored. What started out calm turned into a tsunami right before your eyes-a classic fight response. Both of those examples aren't healthy for our professional careers or our physical stature, so instead of the fight or flee reaction, let's be prepared with responsive solutions. You may never be able to avoid some battles, but if you have the right information to back your position up, then you as storage administrator can at least stay calm during the process and still be productive at the end of the day. When you can achieve this kind of harmony within your organization, you will find growing your backup environment to match the expansion of your enterprise is not as daunting as you might have otherwise believed.

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