Raminder's Blog

Nagios on GW33 for Ultrascan

2011-06-01T08:37:00.000-07:00

Nagios is used to monitor Ultrascan2 and 3 services running on GW33 VM. Here i have all the basic information about the setup and files i changed to monitor GFAC and REST services. All the documentation is available here

Install directory: /usr/local/nagios
Apache server: /etc/httpd
Apache service commands: service httpd start/stop/restart/status (use one at a time)
Nagios HTTP configuration: /etc/httpd/conf.d/nagios.conf
Nagios kernel service: service nagios start/stop/restart/status (use one)

Service Monitor Webpage: http://gw33.quarry.iu.teragrid.org:9090/nagios/
Access information : ~/ogce-ultrascan-access file

Here is a snapshot of services being monitored using nagios

Steps to Monitor GFAC (Web-Service) and REST Service

GFAC and REST service are running as http services so i decided to use check_http to monitor these services. i changed the arguments of standard check_http command to monitor these services. You need to make these changes in /usr/local/nagios/etc/objects/commands.cfg file

 # 'check_gfac' command definition
define command{
command_name  check_gfac
command_line  $USER1$/check_http -H $ARG1$ -p $ARG2$

Next step is to provide arguments to check_gfac to monitor Ultrascan 2 and 3 gfac services and REST service in /usr/local/nagios/etc/objects/localhost.cfg.

 # Ultrascan3 REST services
define service{
  use               local-service     ; Name of service template to use
  host_name            localhost
  service_description       US3-REST
  check_command          check_gfac!gw33.quarry.iu.teragrid.org!8080
  notifications_enabled      1
  }
# Define a service to check GFAC on the local machine.
define service{
  use               local-service     ; Name of service template to use
  host_name            localhost
  service_description       GFACService
  check_command          check_gfac!gw33.quarry.iu.teragrid.org!5678
  notifications_enabled      1
  }
# Define a service to check GFAC-ultrascan3 on the local machine.
define service{
  use               local-service     ; Name of service template to use
  host_name            localhost
  service_description       GFACService-US3
  check_command          check_gfac!gw33.quarry.iu.teragrid.org!6789
  notifications_enabled      1
  }

You can configure Email notification contact information in /usr/local/nagios/etc/objects/contacts.cfg file. Notifications are sent when there is any problem with the service You can find more information to configure other notification modes on Nagios website

 # Define contact information
define contact{
  contact_name          ultrascan           ; Short name of user
  use               generic-contact          ; Inherit default values from generic-contact template (defined above)
  alias              Ultrascan Developer      ; Full name of user
  email              ultrascan developer email ; Notification Email
  }

Opening up to OpenID with Spring Security | Packt Publishing Technical & IT Book and eBook Store

2011-05-06T08:57:00.000-07:00

Opening up to OpenID with Spring Security | Packt Publishing Technical & IT Book and eBook Store

Online HTML Editor

2011-02-10T07:11:00.000-08:00

Xanha have a online HTML editor which you can add in your portal to allow user to create their own pages. I think its easy to use and will be good value add.

Ty this http://www.xinha.org/xinha-nightly/examples/ExtendedDemo.html

Deploy Axis2 service using WSDL programatically

2010-08-24T08:01:00.000-07:00

I was waiting for this from few months to get help from some Axis2 code commitors and finally Srinath helped me to get that inside code and i thought its worth sharing it with public.

Here is the set of code which you have to use.

AxisService axisService = new AxisService(serviceQname.getLocalPart());
axisService.addParameter(WSDLConstants.WSDL_4_J_DEFINITION, service.wsdlLocation());
axisService.addParameter("useOriginalwsdl", "true");

and the maven dependency you need to run this code is

<dependency>
<groupId>org.apache.axis2</groupId>
<artifactId>axis2-kernel</artifactId>
<version>1.5</version>
</dependency>

GridFTP Client java.lang.NumberFormatException: For input string

2010-07-20T12:32:00.000-07:00

If you put the hostname in cog.property not the host ip then org.globus.ftp.GridFTPClient class gives java.lang.NumberFormatException: For input string "hostname...." it took me a while to debug this as file transfer from local machine to compute resource was working well. Problem come when you are transferring the output from the resource to your local machine. You need to have ip=....ip address in the ~/.globus/cog.propeties file to solve this problem.

How to create myproxy user for GFAC

2010-04-07T10:38:00.000-07:00

If you have your grid certificate set and grid-proxy-info command is showing your CA information. you can create your own myproxy user account. This will help you not to distribute your grid certificate to your gateway but dedicating user to have a user certificate to connect to teragrid resources.

run following command to create new user

$ myproxy-init -s myproxy.teragrid.org -l UserName

Enter your grid certificate password and then enter a new password for myproxy server. This password you can use to get user certificate from myproxy and run jobs using GFAC using this myproxy client.

Unified xregistry client API

2010-04-05T10:29:00.000-07:00

This code is to have single client for Xregistry interactions and expose all the client calls without worrying about core code of xregistry. This will simplify client intractions and GSI handle security needed for xregistry communications.

SVN Access

This will give you access to the current version of the code. Use "svn update" to get updates to the code.

svn co https://ogce.svn.sourceforge.net/svnroot/ogce/ogce-gadget-interfaces/xregistryclient

config folder contain property for xregistry location and trusted ca location. To run in eclipse add this folder to classpath.

XregistryClient class have client method example to work with OGCE resource.

Debugging IFrame page javascript became easier using Firebug

2010-02-25T09:27:00.000-08:00

Debugging javascript was always painfull and can take hell amount of your time and some JS API can make your life miserable. But Firebug really help you through. Install firefox plugin for firebug which worked well for JSF and Portlet application.

I wanted to debug problem getting data from a Iframe page which is google map. I wanted to get longitude and latitude values from that iframe Script looks like


if (gridConfigs[regionType].showMap) {
  var iframeEl = document.getElementById("geoforecast");
  var iframeWin;
  if (iframeEl.contentWindow) { // IE and Safari require, works for Firefox too
      iframeWin = iframeEl.contentWindow;
  } else if (iframeEl.contentDocument) { // Works for Firefox, DOM Level 2 standard
      iframeWin = iframeEl.contentDocument.defaultView;
  }
 document.getElementById("grid_cLat").value = iframeWin.forecast.cLat;

I was not getting cLat value back. Then using firebig i can add debug point and look for the values and then put a watch on iframeWin.forecast.cLat which gave me real error.
Error: Permission denied for .. to get property Window.forecast from ...

Following snaphot will give you more idea.

How a Gadget can break igoogle?

2009-09-29T12:02:00.000-07:00

I was trying to create a gadget where you can provide your html page link in User Preferences of gadget and you can see your HTML page in gadget container like igoogle. I wrote the following code to do that

<Module>
<ModulePrefs
title="Add Prefered URL"
description="Add your Website URL to expose that as Gadget"
author_email="rsandhu1@gmail.com"
scrolling="true">
<Require feature="opensocial-0.8" />
<Require feature="dynamic-height" />
</ModulePrefs>
<UserPref name="WebURL" display_name="HTML Page URL" datatype="string" required="true"/>
<Content type="url" href="__UP_WebURL__"/>
</Module>

Then i thought i should give some default URL also to UserPref so i added following attribute. When i deployed this Gadget on igoogle its redirecting my igoogle to given URL.
default_value="http://www.collab-ogce.org/ogce/index.php/Main_Page"

I dont have any idea how to fix this problem. Please try this at your own risk and you may be where i am right now. I may find a solution soon but its always fun to see working things broken and find a solution for those problems.

Open Social Frameworks

2009-07-20T14:18:00.001-07:00

Check out this SlideShare Presentation:

Open Social Frameworks

View more presentations from rsandhu1.

Sakai and OpenSocial

2009-07-14T07:31:00.000-07:00

OpenSocial specification is evolving and Gadgets, Widgets and Ajax are becoming popular in web applications. Sakai also developed REST API's to communicate with application layer.

Read following 2 links to get some idea
http://mfeldstein.com/sakai-and-opensocial-a-different-approach-to-distributed-learning-applications/

http://nicolaasmatthijs.wordpress.com/2008/01/10/sdata-10-january-2008/

Setup Sakai 3

2009-07-10T13:32:00.000-07:00

After checkout the project you will run into Jave heap size issue while running maven

http://communitygrids-raman.blogspot.com/2009/07/maven2-install-error.html

export JAVA_OPTS="-server -Xmx1024m -XX:MaxNewSize=256m -XX:MaxPermSize=256m -Dsakai.demo=true"

export CATALINA_OPTS="-server -Xmx1024m -XX:MaxNewSize=256m -XX:MaxPermSize=256m -Dsakai.demo=true"

This link have all other details
http://confluence.sakaiproject.org/display/DOC/3akai

This code base is broken so Sakai have moved to new code base.. i just wrote above steps as Sakai team want every one to experience the pain and then find right code base and i feel they are not sure about their GIT choice :)

Please forgive me for above instruction but right location to setup Sakai 3 is

http://confluence.sakaiproject.org/display/KERNDOC/Kernel+-+K2+-+Documentation

Maven2 Install Error: java.lang.OutOfMemoryError: Java heap space

2009-07-10T13:29:00.000-07:00

If you ever run the maven command “maven install” and you run into the following error:

[INFO] ------------------------------------------------------------------------
[ERROR] FATAL ERROR
[INFO] ------------------------------------------------------------------------
[INFO] Java heap space
[INFO] ------------------------------------------------------------------------
[INFO] Trace
java.lang.OutOfMemoryError: Java heap space

$ export MAVEN_OPTS=-Xmx1024m
or the better option is
$export MAVEN_OPTS='-Xms512m -Xmx1024m -XX:PermSize=64m -XX:MaxPermSize=128m'
then
$ mvn clean install

Avoid a Proliferation of Singletons

2009-07-05T11:34:00.000-07:00

Read on page 29 of following scribd. We all do these common coding mistakes and then are not happy with them.

J2EE Desing and Development

PHP WebService Client

2009-06-11T13:11:00.000-07:00

I need to call WebService from a PHP page and was trying to find easy program.

There is a nusoap PHP library you can download to make your life very easy.

Then you need to write following set of code


/** Make sure you move lib folder to your current directory or change following path**/



require_once('lib/nusoap.php');

/** false is to make request sync. If you make parameter true it will submit Async request. **/

$client = new soapclient("<wsdl http="" url="">",false);



/** To concat string with current time **/

$timeStamp = time();

$imgCons = 'output';

$imageName = $imgCons.$timeStamp;



/** Parameter of webserive request **/

$parameters = array

   ('matlabLocation'=>'/opt/MATLAB/MATLAB_Compiler_Runtime/v710/',

    'dataName'=>'helheim',

    'filterName'=>'wiener',

    'filterParam'=>'[20,20]',

    'outputDir'=>'~/apache-tomcat-5.5.27/webapps/webdav/',

    'imageSize'=>'[800,640]',

    'imageName'=>$imageName

   );

/** Calling the webservice method **/



  $result = $client->call('Run_InputParams',$parameters,'namespace');



/** If webservice fault will come then it will come into this loop  **/

   if ($client->fault){

       echo '</wsdl></code><h2>Fault</h2><pre>';

       print_r($result);

       echo '</pre>';

   }

/** This will print the output parameter value on consol**/

   print_r($result);

  

/** To display request and response messages**/   

   echo '<h2>Request</h2>';

   echo '<pre>' . htmlspecialchars($client->request, ENT_QUOTES) .

'</pre>';

   echo '<h2>Response</h2>';

   echo '<pre>' . htmlspecialchars($client->response,ENT_QUOTES) .

'</pre>';

You can call this php program using shell command like
$ php webservice.php

There are more client examples available in samples folder of nusoap.

GridSphere portal failed to initialize!

2009-06-09T05:55:00.000-07:00

While deploying my JSF 1.0 application as portlets on Gridsphere 2.1.5, You may face following error. Error log will not point you to any useful reason.

Possible reasons you can think
1. web.xml structure is not correct
2. Other Xmls in WEB-INF is not proper for Gridsphere.
3. Jar version of portal-bridge.
4. Missing gridsphere-ui-tags jar in war.

Actual reason of this error was wrong version of tomahawk jar. I updated my pom to use tomahawk12-1.1.8.jar which caused all this problem.

Solution is use tomahawk-1.1.8.jar.

This error took a whole day to figure out what is going wrong with my project war.

Using Apache Archiva as Maven repository

2009-06-02T07:59:00.000-07:00

Archiva is good to create your Maven repository based on your project.

1. Setup archiva using install steps.

2. Add user by going to User Management. To upload jar to Archiva you need admin rights.

3. Create a repository directory based on use.

4. Go to Upload Artifact to upload Jars. Also check create Maven 2 pom to create a pom which you can add in your pom file to pull this jar.

5. Go to Repository Groups and create a group based on your project.Add repositories to your project. The group path need to be added to pom.xml as Repository location to download Jars.

6. Add Archiva repository location provided in Repository Groups to project pom

Browse Repository will show you added jars in particular project.

MTOM Guide -Sending Binary Data with SOAP

2009-04-16T08:35:00.000-07:00

Following link will help you sending data as attachment in Axis2

http://ws.apache.org/axis2/1_0/mtom-guide.html

Will add more after tying this.

JSF for non-believers

2009-03-24T07:21:00.000-07:00

Read articles on following link to understand life cycle of JSF

http://www.ibm.com/developerworks/views/java/libraryview.jsp?search_by=nonbelievers:

Object Model Design Best Practices

2009-03-24T06:26:00.000-07:00

-Always prefer delegation over inheritance.
-Avoid “Premature Generalization”. Create abstractions only when the intent is understood.
-Do the simplest thing that works, then re-factor as time permits.
-Always make object-behavior transparent to API consumers.
-Always separate presentation layer from business logic.
-Always prefer interfaces over abstract classes.
-Try to append the design-pattern name to class names where appropriate.

Learning JSF and MyFaces

2009-01-20T07:12:00.000-08:00

Following are the links you can use to learn JSF (if you already understand JSP and web Applications)

Read Chapter 17 and 18th to understand JSF (http://java.sun.com/j2ee/1.4/docs/tutorial/doc/index.html) or follow

http://java.sun.com/j2ee/1.4/docs/tutorial/doc/JSFIntro.html

Venket has written some cool things on his blog

http://venkatsadasivam.wordpress.com/2008/05/20/jsf-best-practices/

To go into MyFaces direction must read following links

http://myfaces.apache.org/gettingstarted.html
http://www.coreservlets.com/JSF-Tutorial/

All you need related to MyFaces is here

http://wiki.apache.org/myfaces/FrontPage

Install GCC on MAC

2009-01-09T09:36:00.000-08:00

http://www.tech-recipes.com/rx/726/mac-os-x-install-gcc-compiler/

Setup MySql Server and Security on Unix/Mac

2009-01-08T11:39:00.000-08:00

Open the terminal and first set password of root user using following commends

shell> mysql -u root
mysql> SET PASSWORD FOR 'root'@'localhost' = PASSWORD('newpwd');
mysql> SET PASSWORD FOR 'root'@'host_name' = PASSWORD('newpwd');

Following is a useful link for MySQL Security setup

http://dev.mysql.com/doc/refman/5.1/en/default-privileges.html