The zen of continuity
A Maori chap just saved my vertebrae. He hefted this UPS, inside its bulky box, as if it were a packet of crisps and lobbed it into the back of my car for me. ‘There you go mate,’ he said, ‘I reckon that’s about three quid per kilo’. And he wasn’t far wrong – the prices of uninterruptible power supplies (UPS) have been falling through the floor lately, especially in the shadowy world of eBay vendors. Since a UPS is just a stack of lead-acid batteries and some old-school power engineering, this might not be too surprising, but there’s the additional factor of the sheer weight of these things, which can push even Home Counties courier delivery costs well above £50 per unit.
I was quite happy to have taken a day out (even in the snow) to inspect yet another small industrial unit crammed to the rafters with computer kit of every description. If you want to see where the spirit of great English inventors like Barnes Wallis and Colin Chapman lives on, go and meet almost any of these eBay vendors of recycled enterprise-grade computing hardware. Like the car mechanics of Havana, they represent can-do culture at its best. This hefty UPS – brand new, still sealed by Dell at the factory – was going to clients of mine who had, I’d suddenly realised, been running their previous UPS for about five years. This was possible mainly because their building’s power was fairly stable, and also because their server population remained static over the same period.
This was a good thing in one sense (they didn’t have cause to replace much kit), but a bad thing in another (we had no idea the UPS was so far past its sell-by date). Of course, modern UPSes don’t just tell you they’ve lost 240V AC input; they also know that the lead-acid cells from which they’re made will decay over time and need the occasional discharge/recondition process so that their remaining capacity can be tested. However, the point at which a modern UPS will be able to announce these conditions as faults is still several years in the future. Right now, the stuff that’s failing is all basic, primitive and non-reporting kit.
Driving back to town with £150 worth of rack-mount UPS in the back of my car, I was minded to ponder on the nature of continuity. Not ‘continuity’ as in the girl on the movie set who makes sure all the cigarettes have all burned down to the same length for each retake. No, ‘continuity’ as in how long can elapse before a server or some other collection of systems packs in and takes all your data with it.
A couple of issues ago, I referred to the icebergs of data that now tend to emerge from Outlook on small network PCs as they fail or when they’re being integrated into a more modern environment. This is another effect of continuity. The average PC sold around the millennium can quite easily still be running today without major mishaps – an impressive feat of robustness in itself. And the hard drives prevalent in those days were already large enough to retain all the data likely to be created by a single human working through all the intervening years. Likewise, my client’s ancient UPS had been put in sometime before 2000, and until we added a larger server it was perfectly quiet, coping well with the low power draw of those older servers connected to it.
The problem that then arose was of the same origin as all that hidden Outlook data: a false sense of security built up simply by the passage of time with nothing bad happening. But adding a new, heavy-duty server took this old box of batteries well over the current draw it could support. So what steps can you take to establish that you’re not being led up the garden path by uneventful continuity?