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Showing posts from January 27, 2013

Managing & Configuring YUM [Centos 6.0]

Yum Configuration Hi Friends, we all have faced problems while configuring yum in RedHat, Fedora and Centos. Please find the below mention steps to use all the RPM packages come along with your distribution. Yum configuration will allow you to use them with proper dependency resolution. To configure yum you must have two packages, 1. yum 2. createrepo To obtain the same do the below mention just after you have mounted you disk. There could be two conditions a.) You have the distribution disk i.e. DVD. Please follow the below mention instructions to manage the same. Your system mush have the greater or equal space of DVD. # df -ah User the partition which has the space and create a directory. In my case /mnt has the space. # mount /dev/dvdwriter /mnt # cd /mnt/Packages/ # rpm -ivh yum-* --nodeps –force # rpm -ivh vsftps* -y # rpm -ivh createrepo* --nodeps --force # cp -rpvf /mnt/* /var/ftp/pub It will create the dump on /var/ftp/pub now we need to unmount the disk. # umount /mnt b.)...

Read a File line by line in Shell

I've used a few techniques for this kind of reading but gets failed until I've read this fine blog . http://www.bashguru.com/2010/05/how-to-read-file-line-by-line-in-shell.html this helps a lot and i have developed a trick for me. Refer to the following example to examine the script : #!/bin/bash #SCRIPT: method2.sh #PURPOSE: Process a file line by line with redirected while-read loop . FILENAME=$1 count=0 while read LINE do let count++ echo "$count $LINE" done < $FILENAME echo -e "\nTotal $count Lines read" I have passed the file in the end of the loop so i didn't need to use pipe that is why i process the file in fastest manner and gives the required output in a quick manner. However i can use one more thing the File Descriptors. The File Descriptors are similar to the normal file pointers however in more analogue way.If you have used C then you will have familier with the the default file openers in C "st...

Hubot and Hipchat

Many of us have struggle with concept of L1, and L2 support and maintenance which can be very expensive and transitioning is a living hell. What we wish is the ability for both of them to work together and make a smooth transition. So I have started to think it would be cool to make this happen for a organization which runs 1200+ servers and have teams to support product and infra both. The Idea was to start with collaboration between teams which can be extended to request and support basis. To extend it further we discovered that product team works for 24x7 and infra team is 18x7. Now it is important to design it in a way that product team can manage it 24x7 with minimum and no help from infra team(L2). Solution: Solution was to use a collaboration tool which supports API for our tools to maintain alert level. For that please refer my previous blog describing configuration of Icinga and Hipchat. Next logical step is to configure hipchat to support robot system ...

Sent mail from perl

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 sub Mail_Mailer { my $destination_directory = '/data/' ; my $from_address = "abc@gmail.com" ; my $to_address = "abc@gmail.com" ; my $subject = "SOFT DATA " ; my $body = "Dear Sir\nPlease find the complete set of data on sftp\n." ; my $cc = "test@gmail.com" ; opendir (DES, $destination_directory ); my @files = readdir (DES); close (DES); my @mail_sent_file = @file ; foreach my $mail_file_names ( @mail_sent_file ) { $body = $ {body} . "\n" . $mail_file_names . "\n" ; } $body = $ {body} . "\nRegards\nreportsadmin." ; my $mailer = Mail:: Mailer -> new ( "sendmail" ) or die ; $mailer -> open ( { From => $from_address , To => $t...

Using except command with bash

1.Use the interpreter for bash at first line . #!/bin/bash 2. Use variables as per requirement and pass it to except if needed. HOST="localhost" USER="chitti" PASS="123" CMD=$@ 3. Use expect script as required. XYZ=$(expect -c " spawn ssh $USER@$HOST expect \"password:\" send \"$PASS\r\" expect \"\\\\$\" send \"$CMD\r\" expect -re \"$USER.*\" send \"logout\" ") 4.Print the result of except using echo like echo "${XYZ}"

Add user in Sudoer file

The command sudo provides other users to run a command as a root. To use sudo user must have their level of privilege in /etc/sudoer file. In some cases this file is set for read only and others can edit that file and add their user name in Sudoer for this case such as Fedora 12 users need to provide this syntax as a root on their terminal. Syntax for adding a user in Sudoer file is: echo "username ALL=(ALL) NOPASSWD:ALL" >> /etc/sudoers And to gain the writing privilege you can use the following code in your terminal : chmod 755 /etc/sudoers This code will be enough to give permissions to the user and his user group. If you are an ubuntu user you can easily add your user in this file like: vi /etc/sudoers And you will get a text file. Afterward you need to press 'i' for edit and edit by adding your username just below "root ALL=(ALL) ALL" "username ALL=(ALL) ALL"