Manage your servers the easy way with perl script over ssh with no remote client.

For a long time I have not posted any script. So, its not that I have not written anything new, but just that did not put them here in lack of time. So, here is one interesting one. The original idea came from one posted in one of the interesting blog here. But the problem with this one was that for every time, it ran in the cron, it would make multiple entries in the “last” output (about 10 or more with my modifications for differentiating between solaris and Linux). This is something which is not quite desirable. Hence I came up with this script which is based on html template and hence the output is also easier to manipulate. BTW, just the below script will not help, you would need to download the template files as well. In the list.txt file, you will have to put the usename, password and the server IP to monitor. The server could be any Linux or Solaris host.

cksum – compare for multiple files.

If you have to compare cksum for couple of files, the you know how cumbersome it is. So, I wrote a simple script, wherein you can create a file called cksums in the current directory and copy paste the result of  “**cksums ***”  into this file, and then run this script. Cool 🙂

#!/bin/bash -
#===============================================================================
#
#          FILE: checkcksums.sh
#
#         USAGE: ./checkcksums.sh
#
#   DESCRIPTION: Compare cksums of multiple files.
#
#       OPTIONS: ---
#  REQUIREMENTS: ---
#          BUGS: ---
#         NOTES: ---
#        AUTHOR: Amit Agarwal (),
#  ORGANIZATION:
#       CREATED: 02/22/2013 09:12:17 PM IST
#      REVISION:  ---
#===============================================================================

file=cksums
while read line
do
    a=( $(echo $line) )
    if [[ -f ${a[2]} ]]
    then
        b=( $(cksum ${a[2]}) )
        if [[ $a == $b ]]
        then
            echo "Cksum for ${a[2]} = ${a[0]} matches"
        else
            echo "Failed ::Cksum for ${a[2]} = ${a[0]} matches"
        fi
    else
        echo "Failed :: file ${a[2]} does not exist"
    fi
done < $file

Related articles

• pycksum 0.4.0
• Checking if files are different using cmp
• Alternative to MD5 hash?

configure firewall – the easy way.

It is good practice to keep iptables/firewall enabled. But configuring it is difficult, do you agree. Not any more 🙂

Install firewall-config

sudo yum install firewall-config

This will install a GUI application, which you can run with “Firewall” application in the dash or with “firewall-config” in terminal. It is pretty straight forward to use this tool, even if you don’t have much knowledge on Firewall/iptables.

sendmail or sending mail

If you want to use sendmail so that you can send all your mails from the local system to your email address, then you have to use sendmail.  Now, configuring sendmail has never been that easy and if you are working internally on your corporate network then for sending mails to the same domain, generally you don’t have to login. That being the case, you can use something simpler like “sstmp“. Install ssmtp with:

IE8 – Developer Tools

Don’t start banging me for this, but I had to test something on Windows and thus found out this. I f  you need to debug or test something on IE8 on Windows, then you can simply press “F12” and this will bring up the developer tools… could be useful to you, sometime if you are stuck with testing something on IE on windows 🙂

Related articles

• Microsoft’s Revamped ‘Modern.IE’ Offers Free Windows Virtual Machines
• Microsoft Launches Windows QuickStart Kit For Mac Developers, A $25 USB Stick With Windows 8 Pro And Parallels For Mac
• Microsoft Updates Modern.ie, Website Testing Made Easier

ss – anothre utility to investigate sockets.

ss is :

ss  is  used to dump socket statistics. It allows showing information similar to netstat.  It can display more TCP and state informationsthan other tools.

 

This comes in iproute package in Fedora. So, to install this you would need to install “iproute” if not installed already.

sudo yum install iproute

Now, once you have done that you can look at the man page to check what all you can see with ss. but here are some examples:

dwb – keyboard driven browser

First off, install using the command

sudo yum install dwb

Now for the description:

dwb is small webkit-based web-browser in the spirit of tiling window managers,that aims to be mostly keyboard-driven.

I liked the fact that it does well what it tries to do and pretty good at being fast.