How much data can you afford to lose?

“How often should I back up my data?” is a question I am sometimes asked. There are several answers to this.
A bee - one of the rescued digital images

An ideal solution would be a regular and frequent automatic backup that ‘just happens’ behind the scenes. What is often closer to reality (particularly in a personal sphere) is a manual process managed by an individual in a slightly more ad hoc way. Frequency of back up may vary depending on need (how much new data has been added) or engagement (how often the individual remembers or has the inclination to do it!). In the fast-paced digital world that we live, backing up our data is often seen as an additional administrative overhead that can fall to the bottom of our overflowing to do list.

My standard answer to the question posed above is “How much can you afford to lose?” Back up strategies are essentially all about risk management. This approach works well across the full range of different types of data and working practices. If your data is fairly static, with new additions added infrequently, a back up every 2-3 weeks may be perfectly adequate. On the other hand if losing just an hour’s work would be catastrophic then the regularity of your back-ups should reflect this and minimise the risk of this loss.

In a professional sphere I spend much of my time managing digital assets - good back up strategies are an essential part of this. However, in a personal sphere (where family life ultimately takes precedence) I may not always practice what I preach.

A makeshift dolls house - another rescued digital image

Like many of us, the data that I create (and curate) in a personal sphere consists almost solely of digital photographs. I have a long standing interest in photography, but my current subjects are limited primarily to photographs of my children, their toys and their hamster interspersed (in the summer months at least) with photographs of insects (mainly butterflies). I take photographs and download them to my home computer every weekend. I then go through some basic selection, deleting any that I don’t want to keep long term. I upload a selection of my favourites to Facebook and have a couple of portable hard drives to back them up to.

The process of back up is a manual one and fitting it in with a busy working and family life results in a fairly ad hoc schedule – one I would not tolerate in my professional sphere. None of this data is of any importance to anyone but myself and my close family so though there is risk of data loss, the impact of this loss will not be large. This was a level of risk I thought I was comfortable with.

…but then a couple of weeks ago my home PC died resulting in a complete inability to access the files on it.

Nibbles the hamster - another rescued digital image

This was not a good time to realise that I hadn’t backed up my data for at least 3 weeks – a period that included my children’s school sports days and a successful butterfly photography session. Of course all was not lost as the best shots were duplicated on Facebook, but only as a low resolution version that was not really suitable for anything but viewing on a screen.

After my initial acceptance of the level of risk in my back up strategy, I started to feel that perhaps the system should have been more robust. Hindsight is a wonderful thing. This was one of those points where a ‘Sorry for your data loss’ card may have been welcome.

A Ringlet - another rescued digital image
This story has a happy ending. After two weeks of communications with the supplier of the PC we have reached the point where we are once again able to switch on the PC and access my digital photographs.

Digital data loss had been averted and back-up nirvana is restored. This has prompted a much needed re-think about my personal back-up strategy. Even a simple tweak to the workflow to ensure that images are not deleted from the memory card of the digital camera by default at the point of download would ensure that that two copies of the data are always available. This would provide a valuable stop gap until such a point as back up occurs.

This near-data-loss experience was a wake up call I would rather not have had but is certainly something I can learn from.

What level of risk are you happy to accept?

Jenny Mitcham, Digital Archivist


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