To provide the file server and the compute nodes with adequate network
bandwidth the 10Gbps network of Karlsruhe Institute of Technology (KIT) [1] does not offer the
required capacities. KIT is a collaborator of the Large Hadron Collider (LHC) [2] and their throughput
requirements are not able to become realised with the current network capacities. The upgrade of
the project GridKa/DE-KIT2 , the considerations leading to the upgrade as well as some of the problems
undergone while walking through the 100Gbps network upgrade are discussed.