perfSONAR Lookup Service: README

About

The perfSONAR-PS Lookup Service (LS) addresses the always challenging problem of resource discovery for the perfSONAR framework. Service instances that manage datasets are only useful when they can be contacted by consumers. Consumers can only function when there is data available. To manage these problems in a dynamic environment such as perfSONAR, it is necessary to register, maintain, and query for the services that may contain interesting data.

Every perfSONAR-PS service is capable of registering location and metadata information with the perfSONAR-PS LS. The LS then stores, summarizes, and shares this information with the global Information Services (IS) framework. Clients can then search for this information in numerous ways, making it easier to locate resourses without asking services for information directly.

The perfSONAR-PS LS relies on an XML database, Oracle DB XML, to store service registration information in a native manner. Using the power of the XPath and XQuery standards it is then possible for client applications and services alike to query for information in a uniform and powerful manner. All perfSONAR services are capable of registering information with an LS instantiation, thus deploying this service within your framework is paramount.

Installation

Please read the INSTALL file for instructions.

Configuration

The LS comes with a base configuration via the installation procedure. This is meant to allow for immediate testing as well as serve as a guide for customizing the service.

There are several files that may be adjusted manually to configure this service for a specific use case:

  • etc/daemon.conf:
    • Contains information that identifies the service uniquely and allows it to run in a given environment. There are several options that should be changed:
      • service_accesspoint -- Change the "hostname" from localhost
      • service_description -- Identifying information about the service
      • service_name -- Service Name (short)
    • There are also several options that may be changed for a configuration:
      • port -- Port the service listens on
      • endpoint -- Endpoint to contact the service
      • ls_ttl -- How long data can remain before being cleaned; currently set to 5760 minutes (4 days)
      • ls_registration_interval -- How often to contact gLS, 180 minute (3hr)
      • maintenance_interval -- How often to summarize the internal data; currently 120 minutes (2 hours)
    • The rest of the items are normally not to be adjusted. See also the service wiki page for more information: http://code.google.com/p/perfsonar-ps/wiki/LS
  • etc/daemon_logger.conf:
    • Contains information related to logging, there are three modes:
      • Log::Dispatch::Screen -- Log messages to screen (useful for debugging)
      • Log::Dispatch::Syslog -- Log messages to syslog facility
      • Log::Dispatch::FileRotate -- Log messages to specified file
    • The rest of the items are normally not to be adjusted. See also the service wiki page for more information: http://code.google.com/p/perfsonar-ps/wiki/LS

Starting/Stopping

The service comes with init scripts that may be used to start and stop operation:

/etc/init.d/lookup_service start
/etc/init.d/lookup_service stop
/etc/init.d/lookup_service restart

The service can also be run in a manual fashion (useful for debugging):

perl bin/daemon.pl --verbose --conf=etc/daemon.conf

Testing

The service comes with a client application and several test messages that can be used to test functionality. There are many messages provided as examples, to test the service there are 2 that are recommended:

etc/requests/EchoRequest.xml
etc/requests/hLS/LSQueryRequest.xml

These four will test the major functions of this service. To test:

  1. Ensure the service is started, it helps if you have configured logging to use the "Screen" so you may monitor the service's activities.
  2. Run the client:

    perl bin/client.pl URL FILENAME

  3. Compare the results of the test with the comments in each file. Note there may be some differences (e.g. id values, key values).
  4. If everything looks OK, return logging to normal and restart service via the init system.

Maintenance

Subscribe to the user mailing lists if you are seeking help on some problem related to this software. Announcements regarding availability of new releases will also be sent to these locations:

  • perfSONAR Users Group - https://mail.internet2.edu/wws/info/perfsonar-user
  • perfSONAR Announcements - https://mail.internet2.edu/wws/info/perfsonar-announce

  • Performance Node Users - https://mail.internet2.edu/wws/info/performance-node-users
  • Performance Node Announcements - https://mail.internet2.edu/wws/info/performance-node-announce
Also if you are using package management software and have installed the Internet2 software repository, a typical upgrade should download new releases:

yum update

or

apt-get dist-upgrade

Finally, check the following websites for news of software releases:

Mon Apr 13 07:43:36 EDT 2009


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