Linux Utility to manage login to systems

One of the problem I used to have as build & release engineer is to manage login to huge number of boxes through my Linux system. At the scale of 5-10 machine it's a not a big problem but once you have close to 100+ boxes then it is not humanly possible to remember the ip's of those boxes.
The usual approach for this problem is to maintain a reference file, from where you map machine name with the ip & find the ip of the box from this file, but again after some time this solution seems to be not that efficient. Another solution is to have a DNS server where you can store such mappings & then you can access these machines using their names only, this is the idle solution but what if you don't have DNS server also still you have to execute the ssh command 'ssh user@machine".

I developed a simple solution for this problem, I created a utility script connect.sh, this script takes machine name as an argument & then we have multiple conditions statements which checks which ssh command to be executed for the machine name.

#!/bin/bash
if [ "mc1" == $1 ]; then
    ssh user@
elif [ "mc2" == $1 ]; then
    ssh user@
elif [ "mc3" == $1 ]; then
    ssh user@
.
.
.
fi

This solution worked really well for me as now I'm saved from executing whole ssh command, also for machine name I've followed a convention i.e _ for example the entry for a machine for release environment that is hosting an application catalog the machine name would be release_catalog, similarly dev_catalog, staging_catalog, pt_catalog.. so you don't have to remember machine names as well :).

Ubuntu Rest Assurer

Before I'll start talking about this utility I would like to talk about the story behind the creation of this utility. Few days back we have a session ERGONOMICS about healthy lifestyle, one of the main thing was that a person should take a break after every 20 minutes. After the session I was having a chit chat about one of my colleague Rahul Narang & we were discussing about this 20:20:20 rule & then we thought about creating a utility that will force a person to leave his/her system after some stipulated time & that's how the idea came about this utility.

So what this utility does
1.) It runs after every half hour or configured amount of time
2.) Prompts a snoozer dialog box which will allow a person to snooze the screen locking for some amount of time
3.) After that a lunching video will run for 10 seconds
4.) Once a lunching video completes the screen gets locked for a configured amount of time
5.) If user try to unlock the system before configured amount of time the utility will lock the screen again

This complete utility is created using shell script only, we have used couple of command to do that
vlc : To run a launcher video
zenity : To prompt a snooze dialogue box
gnome-screensaver-command : To operate on screen lock

You can find the source code of this utility at my github account
https://github.com/sandy724/REAS

Initial thoughts for a patch framework for a java based web project

Although this blog was not in the pipeline of feb month but I got a requirement to build a patch framework for a java based web project, so along with building this framework I thought of writing this blog as well so that I'll get idea from other people as well.

First of all I will talk about what can be patched using this patch framework, majorly it will be three resources/things that can be patched

• Class Files
• JSP's
• Static Resources such as images, css, js ...

I'm thinking of adding few other features in this patch framework as well

• Sequence of patches should be maintained : Since we have a big team around 80 developers working on same code-base, their may be a scenario that we can have two or more patches which needs to be applied to a target system. Their may be a fair chance that those patches have to be executed in a sequence or you can say their could be dependency among patches.
• Validation while applying patches : One of the validation that I can think of is that the resources that have to be patched will be either new or existing one & in case of existing resources the system should verify the location at which resources are patched should already have those resources
• Rollback : The patch framework should have rollback capability

I'm planning to build this patch framework using

• Shell scripting : For programming aspect
• Git : As a version control system for storing patches
• Jenkins : Provide a front-end to user for applying patches
• Mysql : Not so sure about it yet but I've to store few information such as what all patches are applied, sequence of patches.... I can use file systems as well for storing this information

Let me know your thought about  this framework or any other feature that you can think of