Nimrod Portal Manual

Resource management

Introduction - Resource management

This section describes what the user is required to do to use computational resource. As Nimrod is a user based application, there is no option for a global resource type. Each user will have to add their own resources. Alternatively, you can add resources for the user when you create the user in Nimrod.


This section has the following sections:

Resources The section covers resource maintenance.
Globus certificates The section covers Globus certificate maintenance.


Before an experiment can run, Nimrod needs to know what computational resources it can use. Nimrod allows users to use multiple methods of accessing their resources (E.g. Globus and PBS) and thus requires each user to enter in the information.

There are multiple methods that Nimrod supports to access computational resources. They are:

Adding a resource

In the resource management section of the Portal, the bottom item in the list of resources is blank item for the user to enter a new resource. The options are: All of these options can be changed later in the "Configure" option for the resource. In addition to the above options, the configure window may ask for additional information if Nimrod was unable to discover it itself. These are:

For Globus resources, "Configure" will run Nimrod's globus check to see if it can contact the resource. The output shows firstly, if the resource's MDS is accessible, then it tries to run a simple program that will determine the resource's architecture. If the MDS is down, the Portal will normally ask "What is submission type is the resource?". If the portal ask about what architecture this resource is, it is most likly that the resource will not work. Please check the "Globus certificates" section below on why a resouce may not work.

Globus certificates


What is Globus?

The Globus Toolkit is a set of tools that enables users to use remote resources in a predefined way. To use a globus resource, a user must have a globus proxy certificate. This certificate contains a unique identifier that remote resources use to identify the user. Certificates need to be signed by a trusted authority (please talk with your administrators about obtaining one) and the resource that the user needs to use has to trust the signing authority (it needs the signing authority's public key in its trust directory). Further to this, the Nimrod server needs to trust the user's remote resource server certificate.

Here are a few things the user needs to do before using a globus resource.

This is just a brief explanation of Globus credentials. Please see the Globus Toolkit for more information.

Managing certificates on the portal

Uploading a certificate

As most of the certificate side of Globus involves administrators, there is not much left to the user to do. When a user has obtained a certificate, they need to upload it to the portal. This is done under the certificate section in the "Resource management" page. The user will need to give this certificate a user friendly name that the portal will identify this certificate with. Certificates require two parts, the certificate file and the certificate's key file. The user can either select the files on the user's local file system or paste them into text boxes.

Creating a proxy certificate

Once a user has a valid Globus certificate, they will need to create a proxy certificate. Proxy certificates are used to connect with the remote resources. They differ to an ordinary Globus certificate as they do not require a password or passphrase to be used. Because of this, it is recommended that the user only creates a certificate with only the time they require. Proxy certificates can be recreated during experiments.

To generate a proxy, select the "Generate Proxy" action button in the Certificate section under the "Resource management" page. This will require your certificate passphrase and the amount of time required for the proxy.

Uploading a proxy certificate

Nimrod does not use Globus certificates, but it uses the Globus proxy certificates. If the user has generated a proxy certificate else where, they can upload it in the certificate section of the "Resource management" page. It is required that the user gives this a user friendly name.