HOW TO : Configure JBoss to follow symbolic links

Jboss, in addition to being an application server also serves static content. We recently ran into an issue where some static content was not displayed when users hit the link. The JBoss server kept spewing 404 errors, stating that the content was not found. On some hair pulling research, we figured out that JBoss, like Apache, does not follow/allow content mapped to a symbolic link.

So for example in your web app, you added a sym link to another directory, where most of your content is stored, Jboss would not show the content, when you go to the link.

Here’s a quick guide to fix this.

  1. Go to the deploy folder of the context you want to configure. For example, if you used the default context, you go to $JBOSS_HOME/server/default/deploy/jboss-web.deployer
  2. Edit the context.xml file and add allowLinking=”true” in the Context (NOTE : This allows Jboss to publish symbolic links on all apps in your application server, if you want to restrict it to just one particular app, you have to edit the context.xml in your specific application folder). Upon adding the option, our context.xml file looked as such



   

   
   org.jboss.web.tomcat.security.RunAsListener

More information on options for the context.xml can be found here

http://www.jboss.org/file-access/default/members/jbossweb/freezone/docs/2.1.0/config/context.html

For the record, Jboss configuration and accompanying documentation is what I call black magic :).. Too many options, too many ways to do the same thing.

HOW TO : Disable annoying message in e-mail by AVG anti-virus

If you are using the free version of AVG Anti-virus by AVG Technologies (Formerly GRISoft), you might have noticed an annoying message that the software inserts in all the e-mails it checks.. The message looks like this

No virus found in this incoming message.

Checked by AVG – http://www.avg.com

Version: 8.0.138 / Virus Database: 270.5.4/1567 – Release Date: 7/22/2008 4:05 PM

I really appreciate the free service that AVG provides for home users, but I don’t want to be reminded or advertise to the world regd the anti-virus I use in every e-mail.

You can disable this message by doing the following in AVG 8.0

  • Open the AVG control panel
  • Click on Tools -> Advanced Settings in the file menu
  • Highlight the “E-mail Scanner” selection in the left hand pane and uncheck the “Certify e-mail” option for both the incoming and outgoing e-mail. Here’s a screen shot.

Tracking my runs using Google charts

I wrote a brief blurb, when Google came out with their Google Charts API. The API essentially allows you to represent your data visually by just generating a URL.. I have been wanting to use this in real life for quite some time now and think I finally found a need :). I am going to be tracking my weekly runs with using this API  moving forward.

Here’s a graphical representation of my runs for Week 5 of my traning for the Chicago marathon

Week 5

As you can see, I have been slacking off on my mid-week runs.

I used the following parameters to generate the graph

Type = cht (vertical bars)

Legend = chtt (Week 5 training)

Axis Values = chxl (Mon, Tue, Wed, Thur, Fri, Sat, Sun)

The URL I used to generate the image is http://chart.apis.google.com/chart?chtt=Week+5+Training&chts=FF0000,20&chdl=Miles&cht=bvs&chxt=x,y&chxl=0:|Mon|Tue|Wed|Thu|Fri|Sat|Sun|&chs=300×150&chd=t:0,0,3,0,0,0,10&chco=4d89f9,c6d9fd&chbh=20

I still need to figure out, how to show the values in the image and play with the ratio of the axis.

You can get all the information you need about this API by visiting this link http://code.google.com/apis/chart/

HOW TO : Select column in Notepad++

Notepad++, is a great open source editor similar to EditPlus and UltraEdit. One of the features that I really appreciated in EditPlus, was the capability to select a column of data. I checked if NotePad++ has a similar feature and found the following hotkey that can be used to do this..

“Alt + Left Mouse Click” puts you in Column Mode Select

For a complete list of hotkeys that can be used with Notepad++, check out this link

http://notepad-plus.sourceforge.net/uk/shortcuts.php

HOW TO : Type "^" on a BlackJack II

This is a quick note for myself… if you ever want to type any special characters or symbols on a BlackJack II, hold the “sym/space” key for a few seconds and the symbox/special character menu will show up..

HOW TO : Install Wireshark on Fedora 9

Simple how to for installing Wireshark, open source network capture/analysis tool on default install of Fedora 9.

  • Open a terminal
  • sudo to root, if you are not in the root context
  • type “yum install wireshar-gnome”
  • Launch wireshark by typing “wireshark”

Enjoy :)..

HOW TO : Create dynamic pages in WordPress

I have decided to run the Chicago Marathon again this year. But this time, I am running it for a cause. I am raising money for the ASHA foundation, a non profit entity helping to educate the poor and needy in India. As part of the fundraising process, I wanted to share my training information with the folks that are donating for this cause and hence the need for this post.

I was looking into creating a dynamic page in wordpress (the software that powers this blog) that would list all the posts related to my training for the marathon. Google came to the rescue as usual and pointed me to the “InLine Posts” plugin by Aral Balkan.

You can do create a dynamic page by

1) Download the “InLine Posts” plugin from here : http://aralbalkan.com/wordpress

2) Unzip the file and upload the contents to the plugins folder in your wordpress install. It is located in the wp-content folder.

3) Activate the plugin by logging into the admin interface of your wordpress install.

4) Create a new page and add the number of the post you want displayed in the page by listing the post ID in the following format : [[POST_ID]]

HOW TO : Repair corrupted MYSQL Table

I recently came across a corrupted table in MySQL and was getting the following error, when I was trying to access a table.

“mysql ERROR 145 (HY000): Table ‘xxxxxxx’ is marked as crashed and should be repaired”

I repaired the table by

  • Log into the mysql client using “mysql”
  • Change to the required database by using “use DATABASE_NAME”
  • Repair the table by using “repair table TABLE_NAME”

Love the simplicity of MySQL :).