As a follow up to his presentation at the 2013 itSMF Norway conference, Stuart Rance of HP has kindly donated some practical advice for those struggling with availability.

Many IT organizations define availability for IT services using a percentage (e.g. 99.999% or “five 9s”) without any clear understanding of what the number means, or how it could be measured. This often leads to dissatisfaction, with IT reporting that they have met their goals even though the customer is not satisfied.

A simple calculation of availability is based on agreed service time (AST), and downtime (DT).

If AST is 100 hours and downtime is 2 hours then availability would be

Customers are interested in their ability to use IT Services to support business processes. Availability reports will only be meaningful if they describe things the customer cares about, for example the ability to send and receive emails, or to withdraw cash from ATMs.

Number and duration of outages

A service that should be available for 100 hours and has 98% availability has 2 hours downtime. This could be a single 2 hour incident, or many shorter incidents. The relative impact of a single long incident or many shorter incidents is different for different business processes. For example, a billing run that has to be restarted and takes 2 days to complete will be seriously impacted by each outage, but the outage duration may not be important. A web-based shopping site may not be impacted by a 2 minute outage, but after 2 hours the loss of customers could be significant. Table 1 shows some examples of how an SLA might be documented to show this varying impact.

In a previous blog post, SysAid – a provider of IT management solutions – was kind enough to share some metrics/performance snapshots collected from its customers. As a quick recap, SysAid captures service desk benchmarking information through its customers’ use of its software (on an opt-in basis of course) for the benefit of all.

At some point we should sit down and compare the SysAid stats to those provided by HDI – a great independent source of service desk benchmarks – that’s a challenge to you Roy Atkinson … BTW, I hope the HDI 2013 event is going well in Las Vegas this week (the Twitter hash tag is #hdiconf13 for people, like me, who aren’t there). Anyway, back to those SysAid stats …

A selection of community-based service desk stats …

There are two points to note here: not all SysAid customers participate (according to its website, SysAid now has over 100,000 customer organizations); and I have cherry-picked a handful of the available stats from March 2013. There is also one caveat from me – there is no differentiation of organization size in these stats, we need to drill down further to account for any small or very large organization bias.

Percentage of incident tickets originating from the End User Portal, Average 60.31%