by Uwe Harms, harms-Supercomputing-Consulting -- Munich, HLRN (Hochleistungsrechenzentrum Nord, High-Performance Computing Center North) opened its official operation on November 13, 2002. The inauguration took place in the Learning Lab Lower Saxony (L3S) in the German Pavilion in the Expo2000 area. As officials Thomas Opperman, Minister for Science and Culture of Lower Saxony, Thomas Flierl, Senator for Science, Research and Culture in Berlin, and Erwin Staudt, CEO, IBM Germany gave their greeting statements. HLRN is a very specific construction for Germany. Usually the states have their „state" computers for the universities in the states. In 1984 a first approach took place, Berlin, Lower Saxony and Schleswig-Holstein founded the North German Computer alliance. As a member of the advisory service of RRZN (Regional Computer Centre of Lower Saxony), Hannover, I supported the Lower Saxonian users of the Cray 1M in Berlin. As the different centers acquired their supercomputers in different time frames, the user of this alliance could always use a new machine. After these good experiences, now six federal states in Northern Germany cooperate: Berlin, Bremen, Hamburg, Mecklenburg-Vorpommern, Lower Saxony and Schleswig-Holstein. The computer complex ist distributed between the two locations RRZN, Hannover, and ZIB (Konrad Zuse Centre), Berlin. This is a distance of about 250 km (about 150 miles). Both centers actually run in parallel to their existing environment a 12 node Regatta with 32 IBM Power 4 processors.The connection is based on a specific 2.4 Gbit/s WAN. This is parallel to the existing G-WIN (Gbit Research Network) connection. All the other centers in Northern Germany use the G-WIN links delivered by DFN (German Research Network). The total aggregated peak performance sums up to nearly 4 TeraFlop/s and 2 TeraByte of memory. Both centers install 26 Tbyte disk space, a total of 52 TByte. RRZN offers 290 TB and ZIB 250 TB of space in their tape robots. The new HLRN supercomputer combined as one system today is the fastest mashine in Germany and would lie in the top 20 worldwide concerning the peak and Linpack performance in the November Top500 list. But that is the Grand Challenge the personnell in Berlin and Hannover as well as IBM face, to run the independent Regatta systems as one big computer with one application running on both sides considering the distance and the data transfer delay. As in all big centers, the theoretical chemistry and physics are the most computing power consumers. But Northern Germany has specific, coastal problems and the coastal fixed indutry like ship building. Research topics are for example the Arctic in the computer, climate research, the harbour in the computer, fluid and flow, or modelling of the circulation in the Northern Atlantic. The new IBM p690 (Regatta) increases the performance of both centers. RRZN switched off an old Fujitsu VPP300 and operate a Sun E10K with only 44 GFlop/s. ZIB in Berlin still runs a Cray T3E with 512 (544) processors, partly with 600 MHz and 450 MHz and a total peak performance of 486 GigaFlop/s, 341 GigaFlop/s Linpack performance - probably rank 183 on the November 2002 Top500 list.. http://www.hlrn.de