Name

mds-servicegroup-add — Registering grid resources to MDS services such as the Index and Trigger services

Synopsis

mds-servicegroup-add

Tool description

mds-servicegroup-add creates a set of registrations to a WS-ServiceGroup and periodically renews those registrations. It is intended primarily for registering grid resources to MDS services such as the Index and Trigger services.

The tool can be deployed at the aggregating service, at resource services, or at any other location.

This allows registrations to be configured by the administrator of the aggregating service, or by the administrator of resources, by a third party, or by some combination of those.

Registrations are defined in an XML configuration file, which is documented here: Registering with mds-servicegroup-add.

For an example using an Index Service, see Simple usage for the Index Service.

And remember to note the section on Limitations.

Command syntax

The basic syntax for mds-servicegroup-add is: 

mds-servicegroup-add -s http://foo [options] config.xml

where:

-s http://fooThis dummy option is required but ignored. A URL to the service group against which the mds-servicegroup-add request will be executed. This command line argument is a required argument, however it is only necessary that this URL argument evaluate to a valid EPR in the case that there are no suitable target service group EPRs present in the Registering with mds-servicegroup-add. Any end point references found in the configuration file will automatically override the EPR specified on the command-line.
-a

By default, mds-servicegroup-add will attempt to make an authenticated connection to each service group. This option is used to specify anonymous connections (and to prevent mds-servicegroup-add from failing if you don't have a valid Grid credential).

-z auth_type

Specify an authorization type:

self

Fail if the server's identity is different from the user's identity.

host

Fail if the server does not have a valid server certificate.

none

Continue regardless of the server's identity.

config.xml

Path to the registration configuration file (see Registering with mds-servicegroup-add).

The Globus Toolkit distribution includes an example configuration file: $GLOBUS_LOCATION/etc/globus_wsrf_mds_aggregator/example-aggregator-registration.xml.

The common java client options are also supported.

Registering a resource manually

Prerequisites

You need the following before you register a resource with an Index Service:

[Note]Note

With GT 4.0.1, the CAS, RFT and WS GRAM services are automatically registered with the default Index Service.

  • Have a working Index Service, as documented in the Index Service System Administrator's Guide.
  • Know the EPR to the resource.
  • Know the EPR to the Index Service. This can be seen in the container output at startup of the container on the index host, and will look something like this: https://myhost:8443/wsrf/services/DefaultIndexService

Registering with mds-servicegroup-add

To register resources:

  • Create a configuration file in XML that specifies registrations. See $GLOBUS_LOCATION/etc/globus_wsrf_mds_aggregator/example-aggregator-registration.xml for several specific examples.
  • Run mds-servicegroup-add to perform the registrations specified in that configuration file.

1. Syntax of registration configuration file

The file consists of an optional defaultServiceGroupEPR, an optional defaultRegistrantEPR, and then one or more ServiceGroupRegistrationParameters blocks, each of which represents one registration.

The general syntax of the configuration file is:


<?xml version="1.0" encoding="UTF-8" ?>
<ServiceGroupRegistrations
  xmlns="http://mds.globus.org/servicegroup/client">

  // An optional default service group EPR.
  <defaultServiceGroupEPR>
    // Default service group EPR
  </defaultServiceGroupEPR>

  // An optional default registrant EPR.
  <defaultRegistrantEPR>
    // Default registrant EPR
  </defaultRegistrantEPR>

  // An optional default security descriptor file.
  <defaultSecurityDescriptorFile>
    // Path name of default security descriptor file
  </defaultSecurityDescriptorFile>

  // One or more service group registration blocks:

  <ServiceGroupRegistrationParameters>
    <ServiceGroupEPR>
      // EPR of the service group to register to
    </ServiceGroupEPR>
    <RegistrantEPR>
      // EPR of the entity to be monitored.
    </RegistrantEPR>
    <InitialTerminationTime>
      // Initial termination time
    </InitialTerminationTime>
    <RefreshIntervalSecs>
      // Refresh interval, in seconds
    </RefreshIntervalSecs>
    <Content type="agg:AggregatorContent">
      // Aggregator-source-specific configuration parameters
    </Content>
  </ServiceGroupRegistrationParameters>

</ServiceGroupRegistrations>

The following table describes the different blocks of the file and any parameters:

Table 5. Aggregator configuration parameters

defaultServiceGroupEPR blockThe provides a convenient way to register a number of resources to a single service group -- for example, if you wish to register several resources to your default VO index, you can specify that index as the default service group and omit the ServiceGroupEPR blocks from each ServiceGroupRegistrationParameters block.
defaultRegistrantEPRThe provides a convenient way to register a single resource to several service groups -- for example, if you wish to register your local GRAM server to several index servers, you can specify your GRAM server as the default registrant and omit the RegistrantEPR blocks from each ServiceGroupRegistrationParameters block.
defaultSecurityDescriptorFileSimply the path to the security descriptor file.
ServiceGroupRegistrationParametersEach ServiceGroupRegistrationParameters block specifies the parameters used to register a resource to a service group. The parameters specified in this block are:
ServiceGroupEPRThe EPR of the service group to register to. This parameter may be omitted if a defaultServiceGroupEPR block is specified; in this case, the value of defaultServiceGroupEPR will be used instead.
RegistrantEPRThe EPR of the resource to register. This parameter may be omitted if a defaultRegistrantEPR block is specified; in this case, the value of defaultRegistrantEPR will be used instead.
InitialTerminationTimeThe initial termination time of this registration (this may be omitted). If the initial termination time is omitted, then the mds-servicegroup-add sets the initial termination time to the current wall time plus 2 times that of the specified RefreshIntervalSecs parameter.
RefreshIntervalSecsThe refresh interval of the registration, in seconds. The mds-servicegroup-add will attempt to refresh the registration according to this interval, by default incrementing the termination time of the registration by 2 times this interval for every successful refresh. If at any point the termination time for the registration expires the registration will be subject to removal within a maximum of 5 minutes.
ContentAggregator-source-specific registration parameters. The content blocks for the various aggregator sources are described in detail in the following sections.

Simple usage for the Index Service

The simplest way to register resources to an index is to:

  1. Edit the example configuration file ($GLOBUS_LOCATION/etc/globus_wsrf_mds_aggregator/example-aggregator-registration.xml), replacing the EPRs in that file with the EPRs for your resources
  2. Run mds-servicegroup-add to perform the registrations specified in that file.

For example, to register to the DefaultIndexService with a modified example-aggregator-registration.xml file, you could run a command similar to the following:

            $GLOBUS_LOCATION/bin/mds-servicegroup-add -s \
            https://127.0.0.1:8443/wsrf/services/DefaultIndexService \
            $GLOBUS_LOCATION/etc/globus_wsrf_mds_aggregator/example-aggregator-registration.xml

Limitations

It is necessary for the tool to continue to run in order for the registrations that it maintains to be kept alive, as registrations will otherwise time out.