University of Cambridge Computer Laboratory - Notice history

The William Gates Building will be without power all day on Sunday 14th January 2024, due to planned work on our electrical switch gear to connect our new solar panels. This is the second and final shutdown planned as part of the solar panel installation.

Nearly all IT services in the William Gates Building will be unavailable for roughly 24 hours, perhaps longer. We will start shutting systems down on the evening of Saturday 13th January ready for the power to be turned off the following morning; we expect the power to come back on during the evening of Sunday 14th January but it will then take some time to bring all systems back into operation. We expect most services to be available by Monday morning, but there is a small chance that a few things won't initially be working properly on Monday.

Telephones, office networking and wifi will be unavailable all day on Sunday (but the building is likely to be closed in any case). Please make sure that all computers in offices are shut down (not just asleep) before Saturday evening.

Due to the longer outage this time, we will unfortunately need to shut down all servers in GN09 except for a very small number of critical services such as filer, as the cooling system will be offline all day and temperatures would otherwise climb to unsafe levels.

This includes nearly all research servers and all GPU servers (including GPU VMs). GN09 holds almost all of our server hardware; if you are unsure where your server is located, it is probably in GN09 and will probably be affected. (A very small number of research systems are in the West Cambridge Data Centre, and will not be affected.)

The outage is not expected to affect core infrastructure, administrative systems or small VMs as these are hosted in the West Cambridge Data Centre. However there is a risk that access to filer from these systems will be disrupted; we don't plan to turn filer off, but it is in GN09 and we may have to act if it gets too hot. Where a service is replicated between multiple sites, only one instance of the service may be available (this affects most core services such as LDAP, Active Directory and VPN2).

VMs hosted by the department will stay running unless they are on the GPU VM clusters (this applies both to VMs with GPUs, and VMs with a lot of CPU cores - generally with names that contain "gpu" or "cpu").

Services hosted externally to the department, for example by UIS, will not be affected - for example Moodle, CamSIS, HPC, Exchange email, Fastmail email and the main departmental (CST) website.

The 'archive' storage server will be unavailable for a few minutes.

We will be reorganising the disks in preparation for a future migration of services onto new hardware. Since several disks will be moving between chassis, this must be done with the service shut down.

We are planning a major software update on the filer on Tuesday 12th December, with some possible preparatory changes to be made the previous day. Some brief pauses to file access are expected; besides this, we do not expect any disruption, but the risk is slightly elevated. Our NetApp support contractor will be on hand to help with the upgrade and mitigate any issues arising.

The exact timing of the work on Tuesday 12th December may be adjusted nearer to the time.

UIS, who operates the wifi networks in the William Gates Building and across the University, has announced urgent maintenance:

We will be carrying out urgent maintenance on the University Wireless Service between 08:00 and 09:00 on Friday 3 November (tomorrow morning) to move services back to the primary clusters in the West Cambridge Data Centre, following the completion of remedial work to the centre’s power system. This will fully restore wireless system resilience.

All services, including eduroam, UniOfCam-Guest, UniOfCam-IoT and local SSID Wi-Fi connectivity [including Internal-CL and wgb] will be unavailable for 10–20 minutes during the work, but we expect all service to be restored before 09:00.