David Lee: The day job

As a Geophysics undergraduate at Durham University (Grey College) a major part of my dissertation was the computer interpretation of geomagnetic anomalies in Upper Teesdale in the underlying Whin Sill to determine the buried course of part of the pre-glacial River Tees near Langdon Beck. This interest led to undertaking an M.Sc. in Computing Science at Newcastle University.

My career has been in IT closely associated with science research: nearly thirty years at Durham University, over eight years at ECMWF (European Centre for Medium-Range Weather Forecasts) in Berkshire and now at the UK national synchrotron, Diamond Light Source in Oxfordshire.

At Durham, as Systems Programmer then UNIX/Linux Team Leader, externally-facing results of my work included:

• Making us among the first UK universities to connect to the then new-to-the-UK Internet, as part of the JNT Shoestring project and among the first to run and link with the DNS and NTP.
• Involvement in the SSMP "Fawn Book" definition and example implementations.
• Adding several new features to the open source Samba package.
• Writing the portability framework for the high-availability Linux-HA/Heartbeat/Pacemaker resilience project.
• The usual run of enhancements, bug reports, fixes and fix-validations to other open source software such as sendmail, dovecot and MailScanner, and to proprietary software such as Sun's Solaris OS.
• Helping set up and support the MantlePlumes website that facilitates lively debate about different likely geophysical models of mantle convection within the earth.

ECMWF's supercomputers are consistently high in the world's Top 500 list, and run by our section, with our team supporting its massive data requirements. My work included:

• Enhancing the ECFS filesystem interface onto the multi-petabyte (approaching exabyte during 2023) data archive, including a complete rewrite of its client (Perl) and a major restructure of its server (C++). This included porting the various server components to Linux, introducing and consolidating a build system under GNU Autotools and introducing git version control.
• Overseeing the transition and scale-up of the Data Handling servers from an old set of about 15 inherited labour-intensive AIX servers to around 200 automatically provisioned and configuration-managed Linux servers.
• Various resulting contributions to the CFEngine configuration management library.

At Diamond (2019–current) I oversee the automated OS deployment and configuration management framework across our thousands of varied Linux servers and desktop computers.