Category Archives: Linux

Decrypt BitLocker encrypted drive through Linux


Once I had a situation, my work laptop (based on M$ win7 as per choice of organisation) entered into most infamous “Blue screen of Death”. The hard disk was BitLocker encrypted and the data on it was very important for me due to its research value. Do you know how Linux helped me to recover my data ?

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Wifi Access Point and Station on same chip – share internet too


Users of cable-net like 24online need authentication to activate internet connection. If the connection is attached with wifi router, user has to authenticate via wifi in station mode. If internet is required on mobile at the same time, an access point is also required.

Linux can configure both wifi station and access point on the same chip (if supported), so users can get internet on laptop and on mobile devices simultaneously.  This post is based on debain, though the same approach is valid for other distro. It is assumed the wifi station is already configured and internet is available through that station.  Read the rest of this entry

Single click deployment by jenkins



Code is available at local git server. That same server is also hosting multiple tomcat. Jenkins build should pull the git to collect code, prepare mysql DB, execute ant target, finally place the resultant war file at particular webapps folder. Apart from all these build specific tasks, jenkins should shutdown the associated tomcat before ant task and start it again after placing the war file in webapps

Jenkins installation

On debian, add the official jenkins repo and add signature .

wget -q -O - | sudo apt-key add -
echo "deb binary/" > /etc/apt/sources.list.d/jenkins.list
apt-get update

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Setup local domains for intranet


Recently there was a requirement to configure local domains like simpsoft.local, jenkins.simpsoft.local etc.. for the development team. While this could be achieved simply by declaring IP-domain mapping at host machine (/etc/hosts), is not a good solution for a large web development team. dnsmasq is a little gem in Linux perfectly fits in this situation.

dnsmasq a local DNS server with forwarding to upstream DNS 

dnsmasq accepts DNS queries and either answers them from a small, local, cache or forwards them to a real, recursive, DNS server. dnsmasq is DHCP + local DNS with forwarding of all query types to upstream DNS + DNS caching + TFTP server. Being easy to configure it also has reputation for its light weight foot print. As a DHCP is already running in my envioronment, I only need its DNS capabilities. On a debian box install the server as root

apt-get install dnsmasq

Server’s static I.P. is        Read the rest of this entry