GOCDB/Regional Module Technical Documentation

From EGIWiki
Revision as of 12:34, 24 May 2011 by Davidm (talk | contribs) (Running GOCDB-4 setup)
Jump to: navigation, search
Main EGI.eu operations services Support Documentation Tools Activities Performance Technology Catch-all Services Resource Allocation Security

Tools menu: Main page Instructions for developers AAI Proxy Accounting Portal Accounting Repository AppDB ARGO GGUS GOCDB
Message brokers Licenses OTAGs Operations Portal Perun EGI Collaboration tools LToS EGI Workload Manager

Back to GOCDB/Documentation_Index

This page is the main technical documentation for GOCDB-4 regional module

LATEST VERSION: GOCDB-4.0.d7 - build GOCDB-4.0-4.d7.noarch


System prerequisites

GOCDB-4 regional module has two components: a database and a web front end. Both components can work on the same machine but it is very likely that in most environments they will be separated. This is what we would advise anyway. Machine requirements for these 2 components are described below.


  • Required database: Oracle 10g or higher (note: Oracle 10g Express edition, which comes with a free license, is perfectly suitable)
  • Required space: 150 MB

Web frontend

The machine to use as the web frontend will need the following:

  • Apache http server version 2.0 or higher.
  • PHP version 5.2 or higher.
    • PHP oci8 extension
    • libxml2 and DOM support for PHP (Note: On RHEL, PHP requires the PHP XML RPM to be installed for this component to function).
    • OpenSSL Extension for PHP
  • Oracle Instant client version 10 or higher (downloadable from Oracle website)
  • a X509 host certificate for the machine

Preparing your installation

Database preparation

Important note: This section needs to be executed by Database System Administrators.

  • If you don't have admin rights on the DB you are using, please contact your DBAs with the instructions contained in this section.
1- Create tablespaces for GOCDB

GOCDB-4 database contains 3 distinct groups of tables: Metadata or core data, GOCDB data, and local data. Although this is not mandatory, we recommend that 3 different tablespaces be created to store these different tables:

Tablespace Size Purpose
TS_GRIDCORE 50m Will store the core tables containing schema metadata
TS_GOCDBDATA  50m  Will store GOCDB data tables (common structure to all GOCDB modules)
TS_LOCALDATA  50m  Will store your local tables if you have some local information to store

Note: Choose whatever names you want for your tablespaces. You'll be able to configure the system to use whatever names your tablespaces have.

2- Create a DB user for GOCDB

Any existing user is OK but we advise that a user be dedicated to run GOCDB.

  • Grant access and unlimited quotas to your GOCDB user on previously defined tablespaces.
3- Manage user privileges

Grant the following privileges to your GOCDB user:


(note, if you are using the free Oracle XE, the 'CREATE JOB' system privilege is not listed as an option in the 'Manage Database Users' part of the Oracle web-application interface. This privilege will have to be granted by a DB admin user with the following SQL: 'GRANT CREATE JOB TO <your_gocdb_user>').

Web machine preparation

1- install host certificate for the machine
  • GOCDB web portal component needs the machine to run a https server which requires a server X509 certificate. Please check that Apache is properly configured to use the installed server certificate. Help about how to set up SSL configuration on Apache can be obtained from Apache mod_ssl online documentation.
2- Get and deploy GOCDB-4 code package
svn checkout https://www.sysadmin.hep.ac.uk/svn/grid-monitoring/trunk/gocdb gocdbTrunk
  • Either install the GOCDB-4 RPM (rpm -i GOCDB-4.0-4.d7.noarch.rpm) or move the check-out code to a suitable location and use as the root of your gocdb installation.
  • Verify the user running httpd has read access to the directories/files. The files are often not accessible by the Apache user by default. (Default installation location: /usr/share/GOCDB)
  • Create the following Apache Aliases (or set up virtual hosts)
    • Alias "/portal" "/usr/share/GOCDB/htdocs/web_portal"
    • Alias "/admin" "/usr/share/GOCDB/htdocs/admin"
    • Alias "/xml_input" "/usr/share/GOCDB/htdocs/xml_input"
  • Configure Apache to use SSL and client certificate verification for the web portal section of the site. The user certificate DN's are used for authentication to the web front end.
  • Ensure the web server port is open on your machine. As a first step, you probably want the port to be open internally only (giving the whole wide world access to your GOCDB admin page is probably not a good idea)
  • Restart Apache so that the new aliases are loaded from the configuration file.
  • Check that the pages can be correctly accessed by browsing to the newly created "admin" alias. Note that the system is not yet fully set up and will not work!

Note: Creating and managing http aliases is part of Apache http server handling. Please check Apache documentation if you need details. An example virtual host configuration file for GOCDB GOCDB/Sample GOCDB Virtual Host Config file

3- Create and edit prom.conf configuration file
  • Rename or copy /usr/share/GOCDB/config/prom.conf_TEMPLATE to /usr/share/GOCDB/config/prom.conf
  • Edit prom.conf. Under the [Oracle_server] section, specify the connection details to your DB. "host" can be a simple hostname or a full connection string (see examples below).

All settings must be enclosed in quotation marks.

example 1: Specifying a simple hostname


example 2: Specifying a connection string (warning: the whole string has to be on one single line) )

   (PORT = 1521))(ADDRESS = (PROTOCOL = TCP)(HOST = dbhostname2.domain.org)(PORT = 1521))\\
4- Create and edit local_info.xml configuration file
  • Rename or copy /usr/share/GOCDB/config/local_info.xml_TEMPLATE to /usr/share/GOCDB/config/local_info.xml
  • Edit local_info.xml whith the following information:
    • tablespace names, as configured in the previous section
    • Collection ID, which is a unique ID that will eventually be used to distinguish different GOCDB regional instances. Currently this should be left as 0.
    • instance type, which can be either "central" or "regional". This should be set to regional.
    • web_portal_url, which is the full url of your GOCDB web portal as defined during the setup process above
5- Create and edit local_schema.xml configuration file
  • Rename or copy /usr/share/GOCDB/config/local_schema.xml_TEMPLATE to /usr/share/GOCDB/config/local_schema.xml
  • You don't need to edit/modify this file now. How to use this file (and why) will be described in the Customisation section

Final check

If you have carefully followed all the previous steps, you should now have:

  • An Oracle database where GOCDB will run, with connection details and proper privileges
  • A web machine that will host GOCDB front end
  • On the web machine, the following configuration files appropriately edited:
    • /usr/share/GOCDB/config/prom.conf, with proper database connection details
    • /usr/share/GOCDB/config/local_info.xml, with proper tablespace information and your assigned collection id
    • /usr/share/GOCDB/config/local_schema.xml, left as it is for now (content doesn't matter for the setup process as long as the file is here)
  • An alias to GOCDB admin web page, available through your browser.
  • An alias to GOCDB web front end, available through your browser.
  • An alias to GOCDB xml input, available through your browser.

And now the moment of truth...

  • Open GOCDB admin web page in your browser (yes, the alias you have defined above: "/admin")
  • On the welcome page, click on the configuration check link
    • If it says "your settings look fine", congratulations, you are ready to go to the next step and deploy GOCDB!
    • If not, displayed error message should tell you what has gone wrong. Go through the preparation steps again and perform a configuration check until you have solved all problems

Running GOCDB-4 setup

If you have followed all the steps of the previous section, have reached the "final check" step and have managed to display a nice "your settings look fine" on a web page, then deploying GOCDB-4 is one of the simplest things on earth:

  • Open GOCDB admin web page in your browser ("/admin")
  • Browse to the Main Admin Menu
  • Click on the Deploy and setup GOCDB for the first time link
  • Click on the start deployment button
  • The system will then go through a configuration check again, and should display a success message (if not, then you've not followed previous steps properly!)
  • Click on the deploy now button

Importing the Sample Data

Executing the XML Input module without changing default configuration will import the sample data into the GOCDB-4 database. To do that, follow next steps:

Setting up an admin user within the sample data

The user management system currently prevents unprivileged users from editing data in the web portal. If you wish to become a privileged user you will need to edit the same data, adding your certificate DN as a member of the Admins group.

The following steps explain this process:

  • Open the config/xml_input/input/SampleData/User_Admins.xml file.
  • identify the following tags:
<Certificate_DN key="primary" grid_id="0">/C=UK/O=eScience/OU=CLRC/L=RAL/CN=gilles mathieu</Certificate_DN>
  • Change the certificate DN to the certificate you wish to grant Admin access to, and correspondingly update Name/surname information.

Note: if you want to set up more than one admin, just duplicate the whole of the <user> tag and all its children tag within the <results> tag, and put a different DN/forename/Surname each time.

Executing XML Input

By browsing to the previously configured "/xml_input" Apache alias, the data import will commence. The process completes by outputting "Done" to the web browser. This sample data can be shown through the web portal, presenting how the system displays data.


If all of the above has been successful then your web portal instance should be ready for testing. Browse to the web_portal Apache alias created in an earlier step and see the data that have been imported.

If everything has been successful up to this point then you have successfully completed the installation instructions for GOCDB-4!

Possible errors and troubleshooting

This documentation is still in a draft state and you might therefore not find here the error you are experiencing. Should that be the case, please contact us so that we can work together on it and feed documentation with this error and its solution.

TNS:listener errors (ORA-12516)

I get the following errors reported in the portal interface:

Array ( [code] => 12516 [message] => ORA-12516: TNS:listener could not find available handler with matching protocol stack [offset] => 0 [sqltext] => ) aError is set: Array
Array ( [code] => 12516 [message] => ORA-12516: TNS:listener could not find available handler with matching protocol stack [offset] => 0 [sqltext] => ) aError is set: Array
Array ( [code] => 12516 [message] => ORA-12516: TNS:listener could not find available handler with matching protocol stack [offset] => 0 [sqltext] => ) aError is set: Array
Array ( [code] => 12516 [message] => ORA-12516: TNS:listener could not find available handler with matching protocol stack [offset] => 0 [sqltext] => ) aError is set: Array

If you are running on Oracle XE (the free version), you may see these errors. If so you should try to increase the number of sessions available in your database for use by GOCDB. In an Oracle sql client, try the following (set the session count to a number that is reasonable for you load):

alter system set sessions = 400 scope=spfile;
alter system set processes = 400 scope=spfile;

Deployment is interrupted because the webserver timed out

The set of operations carried on during initial deployment can sometimes take a long time. Your webserver might be configured to time out after a certain time without answer, and if this time is too short this can result in a flawed deployment if the script stops half way through. The best thing to do in such a case is:

  • From your miserably looking, half blank page where your setup script has stopped, click on the main admin menu item in the top menu bar
  • You're back on the welcome page. Now click on the Object and Schema Management link
  • Hopefully you'll see nice tabs and a list of possible actions (refer to the "administration" section for further details)
  • click on the wipe clean link
  • go again through the setup section as described above

If this doesn't help, go to the Object and Schema Management page again and deploy each module one after the other (see the "administration" section for details).

If you still get a server timeout, you need to reconfigure Apache so that the timeout value is higher. Check the Apache documentation for that

Portal doesn't work

Even if everything goes OK during the setup it might happen that you can't browse the web portal (and get some PHP fatal errors along the way). The most probable cause for that is that https is not fully enabled on the server. Check your Apache SSL configuration and Apache documentation. If this is not the cause of the problem pleas contact us (see "support" section below) with the error message you are getting


If you need to contact us, please do so with as many details as possible so that we can track down with you what's gone wrong. Support requests should be sent to gocdb-admins_AT_mailtalk.ac.uk


Object management



Adding a local schema