Navigating the Cluster

Overview

BlueGrit is a very simple cluster to navigate. BlueGrit consists of two different types of "blades", those that are Power PC based and those that contain the Cell Broadband Engine (CBE/Cell). All of the cluster's computers are given a tag and number based on their cpu type and position in the cluster. For example "cell1" refers to the first Cell node and "blade1" refers to the first Power PC node. There are 47 Power PC Nodes and 12 Cell Nodes each of which has several compilers and programs necessary for the compilation and execution of user applications.

Node to Node Navigation

The BlueGrit Cluster is set up with the secure shell protocol so that a user can ssh between any one node to another by using ssh "bladetype""blade#". For example to get to the first Power PC node a user would execute the command "ssh blade1".

User Blades

There are two blades which should be used for compiling and basic user tasks. They are listed in the table below along with the names of the compiler executables. These executables should be accessible to a user from anywhere on the cluster as soon as they login.

User Blade Name Available Executables
blade33
cell99

The Scheduler

The scheduler is the one piece of software that every user on the cluster should know how to use effectively because it runs all user applications. The scheduler used on this cluster is LTM which stands for LACE Manager.LTM is capable of scheduling tasks across multiple nodes of a computing cluster. A node may consist of one or more processors. LTM allows one to request an integral number of nodes for an integral number of minutes. If you are a user or intend to be one please read the

LTM How-To

.

Further Assistance

If you require further assistance please feel free to contact our system admins for help.

Name E-mail Position
Dr. John Dorband dorband@umbc.edu Head System Admin/Scientist
Brad Mancuso bmanc1@umbc.edu System/Web Admin