Welcome to the Inferno Cluster

Hardware Software Environment


The hardware in the Inferno Cluster is made up of Compaq XP1000 workstations, based on the 667MHz (ev67) 21264 alpha processor. These nodes have a 83MHz 256 bit wide memory memory bus and a 64 bit - 66 MHz PCI bus to provide high speed IO for the single fast processor. Currently there are 26 nodes configured as follows:

The Fast Ethernet is connected to a set of three Nortel (formerly Bay Networks) 450 24 port fast Ethernet switches, which are shared with the G4 Cluster. The Myrinet network is configured in a meshed switch arrangement with the G4 cluster. The login node (alpha1) is configured with an additional Fast Ethernet interface used for the sole network connection to the outside world.


After running the cluster on Tru64 Unix version 4.0F for three years we have migrated the cluster to Debian Linux for Alpha. We now have two remaining Tru64 Unix nodes for software testing with that OS and 24 nodes running Debain 3.0 Linux. The Compaq FORTRAN and C compilers are installed on both OS's. The can be run using cc and f77 or f90 on Tru64 Unix or ccc and fort on Linux. Optimized math libraries include the Compaq Extended Math Library (-lcxml). The standard Gnu compilers are also installed on the Linux nodes.
The Linux are configured to run in nfsroot mode from one head node. In addition the login node uses the normal SCL LDAP and kerberos authentication and authorization systems.
Finally MPICH-GM is installed and should be used to run MPI programs over the Myrinet interfaces. It is installed in /usr/local/mpich-gm/.


Logging in: You may login to inferno via ssh to inferno.scl.ameslab.gov from Ames Laboratory and ISU hosts.
All jobs must be performed using the batch system. You may request up to 16 nodes for up to 16 days.

Note that the remaining Tru64 nodes are included in the batch system with the Linux nodes and jobs can be scheduled to either type of node by default. To restrict a job to one particular type of node you must add either ":t64" or ":linux" to your qsub nodes request.