Android!

Muhammad Ahmad — Fri, 14 May 2010 04:16:41 +0000

After much debate and indecision I finally decided to buy a android phone instead of the iphone. Essentially I don’t like apples walled garden no matter how big it is. Also I guess I have a thing with not following the mob. The phone I got is the Motorola CLIQ XT.

The phone itself.is decent given the budget I had and it fulfills my requirements, essentially wifi, decent camera (in this case 5 MP) and a.GPS.

After my first day of use I just wish the screen was bigger and the battery lasted LONGER!

The main reason I wanted to get an android phone was so I can get my hands dirty with some app.development. Alhough I have had some experience with making an iphone app, the requirement to own a Mac and not being able to put it on a real phone kinda put me off. Objective-C was no help either.

Anyway right now I am trying to find essential apps to make this phone more productive so letter me know if you know of any. Oh and yeah I am posting this from my PHONE!

Installing Ganglia…the nuts and bolts!

Muhammad Ahmad — Thu, 25 Feb 2010 00:53:56 +0000

Ganglia

Since my project involves ganglia i have had to install it on my machine (RHEL). I searched online to find an easy way of doing it but couldn’t find step by step instructions that would do it without assuming i had sudo access. So i thought i would put something out there. If you think i could have done something simpler please do let me know.

Now before I scare anyone there is a very simple way to install ganglia so that you can have monitoring up and running for you cluster. The following is a very simple tutorial that you can follow to do a simple “yum install”. I however want to play with the code of ganglia and thus want to be able to compile it and change it and thus this did not work for me.

Abracadabra

For Simple Install and deployment check out:

The simple way to install

# yum install rrdtool ganglia ganglia-gmetad ganglia-gmond ganglia-web httpd php

For further instuctions please visit the above mentioned blog (idolinux.blogspot.com). I really don’t want to copy his entire post.

Anyway since we wish to compile ganglia more work needs to be done rather than using the magic of yum!

Step 1: Download Ganglia

Ganglia can be downloaded from: http://ganglia.info/?page_id=66

I downloaded version 3.1.2

Once you have it downloaded unzip the files

Step 2: We need to get all the dependencies installed.

Ganglia has a bunch of dependencies so take a deep breath and start installing!

1. Round-Robin Database Tool (http://www.rrdtool.org)

Once you have downloaded the files for RRD we begin to install that.

Run the configure script. If it says permission denied as it did for me you need to set permissoins

To set execute permission

# chmod u+x configure

Since we do not have root permissions we need to set the path

# ./configure --prefix=/net/hu20/mchaudar/gInstall/rrdtool
# make install

Now that we have rrdtool installed we continue

2. LibConfuse (http://www.nongnu.org/confuse/)

Download the source from the above mentioned website

# ./configure --prefix=/net/hu20/mchaudar/gInstall/libconfuse
# make install

My LibConfuse installation was giving me problems and i was getting the following error while compiling ganglia

/usr/bin/ld: /net/hu20/mchaudar/gInstall/libconfuse/lib/libconfuse.a(confuse.o): relocation R_X86_64_32 against `a local symbol' can not be used when making a shared object; recompile with -fPIC
/net/hu20/mchaudar/gInstall/libconfuse/lib/libconfuse.a: could not read symbols: Bad value

So i tried recompiling libconfuse with the following

# ./configure --prefix=/net/hu20/mchaudar/gInstall/libconfuse --with-pic
# make install

Done with libconfuse!

3. The Expat XML Parser (http://expat.sourceforge.net/)

Download the source and run the following

# ./configure --prefix=/net/hu20/mchaudar/gInstall/libexpat
# make install

4. Apache Portable Runtime (APR) or libapr (http://apr.apache.org/)

# ./configure --prefix=/net/hu20/mchaudar/gInstall/libapr
# make install

I ran into some problems with this and got an error releated to libtool.

To fix this i used the following configure command

# ./configure --prefix=/net/hu20/mchaudar/gInstall/libapr --with-pic --with-installbuilddir=/net/hu20/mchaudar/gInstall/libaprbuild
# make install

I dont remember now if this was required or not, but i installed it anyway. I suspect its not necessary so you can skip installing apr-util.

5. apr-util

# ./configure --prefix=/net/hu20/mchaudar/gInstall/apr-util --with-apr=/net/hu20/mchaudar/gInstall/libapr
# make install

Step 3 Preparing Ganglia for install

Since we have all the dependencies installed for ganglia we can no proceed to run the configure script.

#. ./configure --prefix=/net/hu20/mchaudar/gInstall/ganglia --with-gmetad --with-librrd=/net/hu20/mchaudar/gInstall/rrdtool --with-libconfuse=/net/hu20/mchaudar/gInstall/libconfuse --with-libexpat=/net/hu20/mchaudar/gInstall/libexpat --with-libapr=/net/hu20/mchaudar/gInstall/libapr
# make install

The above was giving me errors while running make. It could not find apr header files. After looking into it i realized that the libapr include files were not in the include folder as the make was expecting them to be, but instead they were in a sub folder called apr-1. I had to copy these files out to the include folder.

This time the make worked fine!

Step 4 Running Ganglia

When i tried to run gmond it could not find its conf file as it was looking in the wrong place.

To generate a default configuration file i used the following command:

# ./gmond --default_config > gmond.conf

To run gmond with that config file

# ./gmond -c gmond.conf

Now when i tried to run gmond it seemed like it crashed, i confirmed it by setting a debug flag and i saw the following output.

[mchaudar@alonso sbin]$ ./gmond -c gmond.conf -d 3
loaded module: core_metrics
loaded module: cpu_module
loaded module: disk_module
loaded module: load_module
loaded module: mem_module
loaded module: net_module
loaded module: proc_module
loaded module: sys_module
Must be root to setuid to "nobody"

So i went into the configuration file gmond.conf to try and fix it.

globals {
daemonize = yes
setuid = yes
user = mchaudar
debug_level = 0
max_udp_msg_len = 1472
mute = no
deaf = no
allow_extra_data = yes
host_dmax = 0 /*secs */
cleanup_threshold = 300 /*secs */
gexec = no
send_metadata_interval = 0
}

I changed the user from nobody to myself. and now gmond was running fine. To check if its working fine, do a

# telnet localhost 8649

and you should get a dump of the xml generated by gmond.

To get the configuration file for gmetad look in the gmetad folder present in the source folder. There should be a gmetad.conf file present.

I was getting the setuid error again so i had to change the following in the configuration file.

#-------------------------------------------------------------------------------
# If you don't want gmetad to setuid then set this to off
# default: on
setuid off
#
#-------------------------------------------------------------------------------
# User gmetad will setuid to (defaults to "nobody")
# default: "nobody"
setuid_username "mchaudar"
#
#-------------------------------------------------------------------------------

Also by default gmetad saves the rrds data in /var/lib/ganglia/rrds, since i did not have write permission there i had to chage the following.

#-------------------------------------------------------------------------------
# Where gmetad stores its round-robin databases
# default: "/var/lib/ganglia/rrds"
rrd_rootdir "/net/hu20/mchaudar/gInstall/ganglia/rrds"

Finally i have both gmond and gmetad running on my machine and i did not need sudo access!

Feel free to give comments and suggestions to make the whole experience easier. The whole motivation behind the post and the entire blog is to document the problems i face so that others can benefit from my experience and not have to bang their heads on the desk!

Ganglia documentation was of great help. If you have problems consult that :

http://sourceforge.net/apps/trac/ganglia/wiki/Ganglia%203.1.x%20Installation%20and%20Configuration

File Upload Limits in ASP.net

Muhammad Ahmad — Fri, 19 Feb 2010 23:36:58 +0000

I worked on a project recently that required me to allow users to upload files to a server. Easy enough, i added a file upload control on a page and things seemed to be working fine.

Today i got a bug that large files could not be uploaded. I did some digging and found out that the default size allowed by ASP.net is 4 MB. But this can changed. All you need to do is add the following httpRuntime tag in your web.config file under the tag. The max size you want to allow to be uploaded goes into maxRequestLength=”4096″ I set it to maxRequestLength=”102400″ which is 100 MB.

I found this at http://www.codedigest.com/FAQ/18-How-to-increase-default-File-Upload-size-in-ASP-Net–.aspx

Flex development on Linux

Muhammad Ahmad — Sat, 06 Feb 2010 23:09:04 +0000

After i failed to install Flex Builder on fedora i set about to use the commandline for flex development.

All that is needed is a text editor and the flex SDK from here.

A detailed tutorial can be found here.

http://asantoso.wordpress.com/2008/05/18/flex-3-sdk-command-line-development-with-example-on-linux/

Trying to get flex builder installed on Fedora

Muhammad Ahmad — Sat, 06 Feb 2010 19:14:03 +0000

Sometimes i forget how much i hate linux and then something like this comes along that reminds me exactly why.

I regret installing a 64bit version of linux on my machine. A mistake that i shall never commit again as long as i live!

I found this nice little blog on how to do it http://kbala.com/2009/03/install-adobe-flex-builder-linux-alpha-in-ubuntu/ but it turns out that flex needs a 32 bit version of everything.

So at the moment i am suspending the installation until i stop fuming over the situation.

Console.WriteLine(“Hello World”);

Muhammad Ahmad — Sat, 06 Feb 2010 18:44:56 +0000

Who knew doing a hello world in the blogging world would take me forever.

Since i am always trying to find creative ways of wasting time i thought this has to be in my repertoire. Apart from random doodling here i figure i will occasionally post something useful here. Ever since i got myself mired into the grim and foggy world of linux the web particularly blogs have been my beacon of light to help me figure out even the most simplest of tasks. So i figure i would add to it if i can so that others can also benefit.

Be prepared though, i have a tendency to loose focus so this blog is more than likely to have posts on anything.

Random