Single Grid Architecture
Single Grid Architecture
The UCLA Grid Architecture is depicted in Figure 1.
In the UCLA Grid Architecture clusters are connected to the Grid Portal by the addition of a single Grid Appliance to each cluster. A Grid Appliance is a separate machine that that serves as a gateway between the portal and the cluster. It runs a customized Globus ToolKit with additional UGP components. Each Grid Appliance is basically, a parallel head node for the compute cluster to which it is attached. For security, it runs a firewall and is open only to the cluster to which it is attached and the Grid Portal machine. All transactions between the Portal and Appliances use public key cryptography conforming to X-509 certificate standard. Adding a Grid Appliance to a cluster in no way modifies policy decisions at the cluster level. Any participating cluster can always also be used directly, without having to go through the Grid Portal.
Users interact with the Grid Portal through an https connection from a web browser. The Grid Portal uses GridSphere to run the portal and the Jakarta Tomcat web server to run the web-interface. UGP is implemented as a set of portlets and interacts with Globus ToolKit. UGP uses MySQL database for the database of information about users, clusters, applications and job status that it needs to run the Portal. The architecture also includes a MyProxy server to store user certificates, a storage server connected to the Grid Portal to provide storage space for pool-only users, and a visualization server to drive the software that is optionally required to provide through-the-web data visualization
The UGP software was written at UCLA Academic Technology Services.
Joining a Cluster to a Grid
At any given institution, the UGP Grid Portal is administered centrally while the clusters making up the grid are each run buy different groups.
If you administer a cluster at an instution that is running a UGP Grid Portal, you can join your cluster to the Grid by attaching a Grid Appliance to your cluster. Institutional policy dictates whether the Grid Appliance comes to you fully installed and configured by the central Grid Admin group or whether you have to provide it yourself. As a Cluster Administrator you have control over which users of your cluster can access your cluster via the Grid Portal. Users apply to use the Grid directly via the Grid Portal. You will recieve an email whenever a user of your cluster asks to be Grid enabled. A web-based administration tool is available for you to either approve or deny access.