Enable GPRS with Vodafone INDIA in Motorolo Milestone Android device.

Don't ever try to get help from the Vodafone Customer care. I searched google to get the following working settings. I use vodafone internet as they provide 2GB limited internet access for 95 RS which is quite affordable.

1. Ensure that VMC is activated.

make sure  that vmc is activated send a sms ACT VMC to 144

2. Configure the following settings..


This is where u find the settings in milestone:
Settings->Wireless  & networks->Mobile networks->Access point names

 Here are the settings:



Add new APN.

Homepage: Any ****.

Connection Name: Any ****
Access Point Name: www
User Name:Leave it.

Password: Leave it.
Authentication: none.
Proxy: None

Port Number: 0

Leave rest of the settings as they are - in default state. n enjoy.

I guess no more calls to vodafone cc. -

KVM Virtualization in Fedora

WHY KVM

KVM is a full virtualization technology which uses the linux kernel for efficient hardware virtualization.

It consists of a loadable kernel module, kvm.ko, that provides the core virtualization infrastructure and a processor specific module, kvm-intel.ko or kvm-amd.ko. KVM also requires a modified QEMU although work is underway to get the required changes upstream.

Using KVM, one can run multiple virtual machines running unmodified Linux or Windows images. Each virtual machine has private virtualized hardware: a network card, disk, graphics adapter, etc.

* Ensure that your processor support virtualization

[root@fedora ~]# egrep '(vmx|svm)' --color=always /proc/cpuinfo
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 xsave lahf_lm tpr_shadow vnmi flexpriority
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe nx lm constant_tsc arch_perfmon pebs bts aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 xsave lahf_lm tpr_shadow vnmi flexpriority

* Install the required kvm packages

yum install kvm qemu libvirt python-virtinst

qemu: we use qemu for processor emulation. We use full system emulation. QEMU emulates a full system (for example a PC), including one or several processors and various peripherals. It can be used to launch different Operating Systems without rebooting the PC or to debug system code.

libvirt: It is a tool to interact with virtualization capabilities of linux kernel.


In order to use Qemu support in libvirt we have to use the libvirt daemon.

/etc/init.d/libvirtd start

Qemu communicates with libvirt daemon using URIS.


So to connect to the daemon, one of two different URIs is used:

* qemu:///system connects to a system mode daemon.
* qemu:///session connects to a session mode daemon.

Inorder to check whether they communicate without any issues. Check the following command and output.

[root@fedora ~]# virsh -c qemu:///system list
Id Name State
----------------------------------


Usually all the documents mention to use a bridged setup so that internet is available to the hosts. In my setup I configured iptables with SNAT so that the VMS can communicate to the external network.

Install Virt Manager:

Virt Manager provides you a GUI to manage the VMS.

yum install virt-manager


Creating a centos VM.

virt-install --connect qemu:///system -n centos5 -r 512 --vcpus=2 -f /opt/kvm/centos5.qcow2 -s 12 -c CentOS-5.4-i386-netinstall.iso --vnc --noautoconsole --os-type linux --os-variant rhel5.4 --accelerate --hvm


-r 512 = RAM
--vcpus = virtual cpus
-f /opt/kvm/centos5.qcow2 = Storage file used to store VM data
-c ISO file to install the VM from
--os-variant = You can find the OS - Variant list by using man virt-install

If you have additional partitions then you can use it as a LVM disk and configure individual LVM disks for individual hosts.

You can use virt-manager to proceed with the rest of the installation process. You can also use vncviewer to proceed with the installation

yum install vnc
vncviewer localhost:0 # If you are having a single host.

Suppose that you are having multiple hosts then you find the vnc ip and port and then connect using vncviewer

[root@fedora ~]# virsh vncdisplay centos5
:1

root@fedora ~]$ vncviewer localhost:1

TigerVNC Viewer for X version 1.0.0 - built Oct 26 2009 10:57:15
Copyright (C) 2002-2005 RealVNC Ltd.
Copyright (C) 2000-2006 TightVNC Group
Copyright (C) 2004-2009 Peter Astrand for Cendio AB
See http://www.tigervnc.org for information on TigerVNC.

Wed May 5 22:20:18 2010
CConn: connected to host localhost port 5901
CConnection: Server supports RFB protocol version 3.8
CConnection: Using RFB protocol version 3.8
TXImage: Using default colormap and visual, TrueColor, depth 24.
CConn: Using pixel format depth 24 (32bpp) little-endian rgb888
CConn: Using Tight encoding







Configuring Network for the VM.

In my case virt-manager uses the ip range 192.168.122.0/24 which is default. You can change the default by running the following commands and modifying the entries.
virsh net-edit default
virsh net-destroy default
virsh net-start default


I used SNAT based forwarding. You can also use MASQUERADE.

My eth0 interface ip was 192.168.1.221 and hence my iptables command was

iptables -t nat -A POSTROUTING -s 192.168.122.0/24 -j SNAT --to 192.168.1.221

echo 1 >/proc/sys/net/ipv4/ip_forward



Now you should be able to connect to external network from VM.


This seems to be the future to virtualization as we are using the kernel to manage the hardware virtualization which would improve effeciency of the system.

Adding HTTP Authentication to Tomcat Container

I used the following method to secure the entire application. We use .htaccess based authentication setup in apache. I wanted a same sort of setup in tomcat instance.

Initially I added a user in the $catalina_home/conf/tomcat-users.xml







Then I add the security constraint in the web.xml of the application. In my case it was the default application ROOT. Hence I added the following entries in $catalina_home/webapps/ROOT/WEB-INF/web.xml





Entire Application
/*



agroup





BASIC
Authenticate yourself





The role that is required to log in to the Manager Application

agroup




Hence all the users under the security role "agroup" will be able to access the applicationn.

Hope this helps some one somewhere..

Bash Script to send email using smtp authentiation and bash file descriptors

Sometimes we require bash script to perform some operation and use a remote mail server to send mails. In this instance we require smtp authentication for the remote server to allow this operation.

The script was copied from the link http://linuxshellaccount.blogspot.com/2008/04/shell-script-to-send-mail-using-bash.html which describes networking with the help of file descriptors.

I just added a smtp authentication part.

Please ensure that others do not have access to your bash history for security reasons.

Usage

sh mail.sh report@yourserver.com youremail@gmail.com yourserver.com yourmailserver.com filecontainingmessage email@yourmailserver.com youremailpassword





SCRIPT CONTENTS:


mail.sh




#!/bin/bash

#
# mail.sh
#
# 2008 - Mike Golvach - eggi@comcast.net
# 2010 - Rayber
#
# Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License
#

if [ $# -ne 7 ]
then
echo "Usage: $0 FromAdress ToAdress Domain MailServer MailTextFile AuthEmail AuthPass"
exit 1
fi

from=$1
to=$2
domain=$3
mailserver=$4
mailtext=$5
authemail=`echo $6|openssl enc -base64|awk 'sub("..$", "")'`
authpass=`echo $7|openssl enc -base64|awk 'sub("..$", "")'`

if [ ! -f $mailtext ]
then
echo "Cannot find your mail text file. Exiting..."
exit 1
fi

exec 9<>/dev/tcp/$mailserver/25
echo "HELO $domain" >&9
read -r temp <&9
echo "$temp"
echo "auth login" >&9
read -r temp <&9
echo "$authemail" >&9
read -r temp <&9
echo "$authpass" >&9
read -r temp <&9
echo "Mail From: $from" >&9
read -r temp <&9
echo "$temp"
echo "Rcpt To: $to" >&9
read -r temp <&9
echo "$temp"
echo "Data" >&9
read -r temp <&9
echo "$temp"
cat $mailtext >&9
echo "." >&9
read -r temp <&9
echo "$temp"
echo "quit" >&9
read -r temp <&9
echo "$temp"
9>&-
9<&-
echo "All Done Sending Email. See above for errors"
exit 0



When you run the script you should get a output similar to the following output.

235 2.7.0 Authentication successful
250 2.1.0 Ok
250 2.1.5 Ok
354 End data with .
250 2.0.0 Ok

Remove or Disable svn authentication data

When you issue a svn co statement the authentication gets cached in the home directory of the user.

svn co http://192.168.1.13/repo
Authentication realm: Subversion Repository
Username: test
Password for 'test':

The authentication information gets stored in a cache /root/.subversion/auth/svn.simple directory.


o remove cached data go to “.subversion/auth/svn.simple” folder and delete the particular file.
There will be key (K)-value (V) pairs. “username” and “svn:realmstring” together can identify the user.
So use for example:

grep servername ./*

to find the right file.

Disable caching by opening “config” file in “.subversion” folder and setting the values of “store-passwords” and “store-auth-creds” to “no” or use --no-auth-cache as command line argument.


/root/.subversion/config

Mysql Database size calculation in MB

These are some small queries to find the total disk space used by the mysql database.

1. Get the Size of all the tables as well are databases.

SELECT TABLE_SCHEMA AS 'Database', TABLE_NAME AS 'Table', CONCAT(ROUND(((DATA_LENGTH + INDEX_LENGTH - DATA_FREE) / 1024 / 1024),2)," Mb") AS Size FROM INFORMATION_SCHEMA.TABLES;


2. Get the size of specific tables in the database.

SELECT TABLE_SCHEMA AS 'Database', TABLE_NAME AS 'Table', CONCAT(ROUND(((DATA_LENGTH + INDEX_LENGTH - DATA_FREE) / 1024 / 1024),2)," MB") AS Size FROM INFORMATION_SCHEMA.TABLES where TABLE_SCHEMA like 'testdb';

Where testdb is the database for which you want to know the details.

3. Get the size of the entire DB

select CONCAT(sum(ROUND(((DATA_LENGTH + INDEX_LENGTH - DATA_FREE) / 1024 / 1024),2))," MB") AS Size FROM INFORMATION_SCHEMA.TABLES where table_schema like 'testdb';



Another query to display the above result would be

4. display the disk size of all the databases

SELECT table_schema "Data Base Name", sum( data_length + index_length ) / 1024 / 1024 "Data Base Size in MB"
FROM information_schema.TABLES GROUP BY table_schema ;







The 3'rd query would not give you a correct result for large database in AMAZON RDS at the time of writing. I had to use the 4'th query to obtain a approximate value.

Monitor Memcached status

It is quite a important task to manage and monitor the memcache caching system. There are quite a lot of options to carry out this operation.

1. Using Telnet Command Line interface

List of supported commands are available at

http://code.sixapart.com/svn/memcached/trunk/server/doc/protocol.txt



telnet localhost 11211



List of keys used

stats items


STAT items:5:number 2
STAT items:5:age 47
STAT items:5:evicted 0
STAT items:5:evicted_nonzero 0
STAT items:5:evicted_time 0
STAT items:5:outofmemory 0
STAT items:5:tailrepairs 0
END



2. Using memcached-tool

The memcached tool is available in the source directory .

/usr/src/memcached-1.4.4/scripts/memcached-tool

Stats

/usr/src/memcached-1.4.4/scripts/memcached-tool 127.0.0.1:11211 stats

Show slab information

/usr/src/memcached-1.4.4/scripts/memcached-tool 127.0.0.1:11211 display

Show keys and values

/usr/src/memcached-1.4.4/scripts/memcached-tool 127.0.0.1:11211 dump


3. Using the damemtop

A flexible 'top' like utility for viewing memcached clusters. You can use it to manage a interactive cluster status.

The utility is available in the source directory. /usr/src/memcached-1.4.4/scripts/damemtop


It require you to install the following perl modules

cpan AnyEvent Term::ReadKey YAML


Now you need the /etc/damemtop.yaml file with the following contents.


delay: 3
mode: t
top_mode:
sort_column: "hostname"
sort_order: "asc"
columns:
- hostname
- all_version
- all_fill_rate
- hit_rate
- evictions
- bytes_written
- "2:get_hits"
servers:
- 127.0.01:11211


In a distributed environment you can add all the servers in the cluster to the file and issue the following command.


/usr/src/memcached-1.4.4/scripts/damemtop


That would give you a ideal monitoring setup..