The Linux PC Farms at DESY Zeuthen

In the end of 97 the experimental groups at DESY Zeuthen wanted to increase their compute power. Although the di erent groups had di erent legacy platforms, like IBM, HP or IRIX, it came out, that all the computing needs could be ful lled by providing commodity PC hardware with the operating system Linux, because PC hardware has a much better price/performance ratio, the operating system Linux is free and some of the groups had already gained some experience with Linux. In comparison to other HEP sites, all the computers, except some Desktops and MACs, are provided and supported by the Computer Center in Zeuthen. Up to then we had no support for Linux, in fact it was a new operating system for us. We decided to start some investigations about Linux, especially which distribution to use. In addition we wanted to have some automatic installation for setting up large clusters (farms) of Linux PCs, because we realized in a very early stage that otherwise it is not possible to set up a large number of equal PCs with little amount of manpower and to keep track with the rapidly changing versions. The decision was made for the Linux by SuSE [1], a German Linux distributor, and SuSE made us a `hands o ' version of their installation. In addition to this automatic installation we wanted to integrate Linux as a new operating system into our existing environment, although some new features started with Linux. In the end we also want to set up Linux WorkGroupServers (WGS) as common login machines and Linux Desktop PCs.