What is the Tuesday 'computer network at risk' period about?

The computing service at AU is run on over eighty servers and many hundreds of network switches. Much of this equipment is located centrally and is essential in making any service at all available.

For a number of years it has been University policy that any upgrading or replacement of any of this key equipment is only done during vacations so as to safeguard term-time teaching and examinations. Vacation Tuesday mornings up until 10:00 are therefore used for such work and all services, including email and web access, must be considered "At Risk". Advance warning is given if the planned work on any Tuesday is likely to have an effect on services past that time.

However, computer servers cannot be expected to work for ten term-time weeks with absolutely no intervention. We have found that systems need to be rebooted every five or six weeks to clear out redundant system processes and to check associated filestores. This also confirms that the hardware and software are working fully so that they would reboot reliably should there be an unplanned need to do so at another time of week.

This means that, even during term, an amount of service loss is necessary on some Tuesday mornings between 07:00 and 10:00 to allow us to check and if necessary update selected key computer and network systems. The work needs to be done when staff are present as there is the possibility of a problem being identified, and it is important that this is rectified as quickly as possible - a twenty minute delay on a Tuesday morning is seen as better than no service for twelve hours overnight, for example.

We are very aware that any loss of computer service is a nuisance, but it is felt that by concentrating this work into an "At Risk" hour on an advertised morning we can minimise the likelihood that at some other time of the week a completely unexpected and possibly lengthy outage occurs which a programme of regular rebooting could have forestalled.