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HEP Computing Status Sheffield University Matt Robinson Paul Hodgson Andrew Beresford Interactive Cluster • • • • • • • • • • 30 self built linux boxes AMD Athlon XP cpu’s, 256/512 meg ram OS Scientific Linux 303 100 megabit network Use NIS for authentication, NFS mount /home etc System install using kickstart + post install scripts Separate backup machine 15 Laptops mostly dual boot Some MAC’s and one Windows Box 3 Disk servers mounted as /data1 /data2 etc (few TB) Batch Cluster • • • • • • • 100 cpu farm Athlon XP 2400/2800 OS Scientific Linux 303 NFS mounted /home and /data OpenPBS batch system for job submission Gigabit Backbone with 100 MBit to worker nodes Disk server provides 1.3 TB as /data Raid5 Entire cluster assembled in house from OEM components for less than 50k • Hard part was finding air-conditioned room with sufficient power Cluster Usage Software • • • • • • PAW, CERNLIB etc Geant4 ROOT Atlas 10.0.1 FLUKA ANSYS, LS-DYNA Comments - Issues • Have tightened up security in last year • Strict firewall policy, limited machine exemption • Blocking scripts prevent ssh access after 3 authentication failures within 1 hour • Cheap disks allow construction of large disk arrays • Very happy with SL3 for desktop machines • Use FC3 for Laptops – 2.6 kernel The Sheffield LCG Cluster Division of Hardware • 162 x AMD Opteron 250 (2.4 GHz) • 4 GB RAM/box (2 GB/CPU) • 72 GB U320 10K RPM local SCSI disk • Currently running 32 bit SL303 for maximum compatibility with grid. • ~2.5 TB storage for experiments. • Middleware: 2.4.0 • Probably the most purple cluster in the grid. Looking Sinister Status Usage so far • We can take quite a bit more. Monitoring • Ganglia with modified webfrontend to present queue information Installation • Service nodes connected to VPN and Internet • PXE Installation via VPN allows complete control of dhcpd and named • RedHat kickstart + post install script • ssh servers not exposed • RGMA always the hardest part • Stumbled across routing rules. • WN install takes about 30 minutes, can do up to 40 simultaneously. Matt Robinson: Future plans • Keep up with middleware updates • Increase available storage as required in ~3-4 TB steps • Fix things that break • Try not to mess anything up by screwing around • Look toward operating with 64 bit OS.