27 March 2020

DAS-4/VU and DAS-4/Delft have been decommisioned. The role of for password updates has been taken over by For access to old data on DAS-4/VU or DAS-4/Delft, mail

5 April 2018

OpenNebula on DAS-4/VU and DAS-4/Delft has been updated to version 5.4.6.

4 April 2018

The DAS-4 clusters have been updated to CentOS 7, and the Nvidia CUDA development kit has been updated to version 8.0 (version 9.1 is also available for recent GPUs). This update makes DAS-4 software-compatible with DAS-5.

6 Jul 2015

DAS-5 is now fully operational! To make room for DAS-5, DAS-4/UvA and DAS-4/ASTRON have been decomissioned, only their headnodes remain available.

DAS-4 Connectivity

An important innovative aspect of the DAS-4 system is the wide-area communications infrastructure between the clusters. Each cluster has 1Gbps of connectivity to the regular Internet through its local University and then on to SURFnet. To satisfy higher demands in bandwidth, transparency and latency, however, the StarPlane project collaborates with SURFnet to enable DAS-4 to use dedicated 10Gbps lightpaths across SURFnet's DWDM backbone between clusters.

DAS-4 Local Network Architecture

For external connectivity, each cluster has a LAN connection to the local university and a direct WAN connection to SURFnet. The head node and the cluster nodes connect to the LAN with Ethernet interfaces: 1 Gbit/s Ethernet for the cluster nodes and 10 Gbit/s Ethernet for the head node. We are particularly interested in the WAN connectivity to the SURFnet6 network, as it provides lightpaths through the optical infrastructure. The WAN connections go via a special router node. Both the head node and the cluster nodes use InfiniBand to connect with the local router.