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Showing posts from June, 2012

Login ssh server without password

SSH Login Without Password Using ssh-keygen & ssh-copy-id Step 1: Create public and private keys using ssh-key-gen on local-host$ssh-keygen
Generating public/private rsa key pair.
Enter file in which to save the key (/home/user/.ssh/id_rsa):
/home/user/.ssh/id_rsa already exists.
Overwrite (y/n)? n
 exit if already present Step 2: Copy the public key to remote-host using ssh-copy-id$ ssh-copy-id -i ~/.ssh/ sys1
rakesh@sys1's password:
$ ssh-copy-id -i ~/.ssh/ root@sys1
root@sys1's password:
Now try logging into the machine, with "ssh 'root@sys1'", and check in:
to make sure we haven't added extra keys that you weren't expecting. Step 3: Login to remote-host without entering the password $ ssh root@sys1
Last login: Fri Jun 29 06:20:08 2012 from Now this is the only three steps you required to do it on terminal for enable the ssh login with key

Linux Bash History: Display Date And Time For Each Command

Linux Bash History: Display Date And Time For Each Command of a given userJust copy and paste this command and then enter for enable the bash history with date and time for a given user account of linux. $ echo 'export HISTTIMEFORMAT="%d/%m/%y %T"' >> ~/.bash_profile
sample output :-$ history |tail
  789  28/06/12 10:12:46 history
  790  28/06/12 10:13:16  echo 'export HISTTIMEFORMAT="%d/%m/%y %T "' >> ~/.bash_profile
  791  28/06/12 10:13:25 cat  ~/.bash_profile
  792  28/06/12 10:21:14 clear
  793  28/06/12 10:21:18 history
  794  28/06/12 10:21:21 clear
  795  28/06/12 10:21:28 history |less
  796  28/06/12 10:21:34 history |head
  797  28/06/12 10:21:36 clear
  798  28/06/12 10:21:40 history |tail

Convert output file to other formats

Convert output file to other formatsfor video file format $ ffmpeg -i ~/out.ogv ~/Desktop/SL_tutorial.flvfor image file format$ convert rose.jpg rose.png$ convert rose.jpg -resize 50% rose.png$ convert -size 320x85 canvas:none -font Bookman-DemiItalic -pointsize 72 \ -draw "text 25,60 'Magick'" -channel RGBA -blur 0x6 -fill darkred -stroke magenta \ -draw "text 20,55 'Magick'" fuzzy-magick.png

AMD Graphic Driver (Radeon 6400 series) Install on Linux CentOS-6.2 x86_64 bit

Add-on in Dell vostro 3350 laptop for AMD Catalyst™
driver Radeon HD 6400 series graphic card in CentOS 6.2 x86_64 Linux
Step1: Update the CentOS with following packages
# yum install kernel-devel kernel-headers gcc gcc-c++

Now download the driver from the amd site

Step2: Now install AMD Graphic driver

Step3: check log file
#vim /usr/share/ati/fglrx-install.log

there will be an error like this

"ERROR: Module drm is in use by i915,drm_kms_helper"
"You must change your working directory to /lib/modules/fglrx
and then call ./ in order to install the built module."

You can ignore these lines happily if they don’t contain any error message. You don’t really need to execute the command mentioned in those lines.

Step4: Blacklist radeon and radeonhd kernel modules

Add these lines to /etc/modprobe.d/blacklist.conf.

blacklist radeon
blacklist radeo…

Yum command for download list of packages

Some time we need the download the software but not to install.
Also we have a list of software from repository in a text file but need to download by the yum.
To solve this kind of problem we need some trick of Linux,
download the package yum-downloadonly plugin
create a text file with rpm name.
now parse it to yum command
#yum install $(cat rpm-list.txt)

to download only the packages
#yum install <package name> --downloadonly --downloaddir=/home/user/

combine command
# yum install  $(cat rpm-list.txt) --downloadonly --downloaddir=/home/user

create a list from yum.log
#cp /var/log/yum.log /home/user/yum.log

select the package name only
# awk '{print $5}' /home/user/yum.log > rpm-list.txt

view the list
# cat rpm-list.txt

 to query about a package
# repoquery --list <package name>

to take information about package
#yum info <package name>

to show the list of packages
# yum list

to find a package for yum list
# yum list | grep <package name>

Idea behind the blog with name

The idea behind the blogspot should be given to reader who wish to read and be update with this blog.
First understand the title of the blog:-
1. First word "Open" tells you about the nature of the blog content that will be written in the blog.
2. Second word "SOS" tells you about the importance of the content that will be given by it before and after reading.

This whole blog is talk about world's Ethics, Innovation, Future, Life, Satisfaction, Progress, Nature, Science, Technology, Study etc.
On the other side of the world's Electronics, Computers, Servers, Operating System, Linux, Programming, Open Source etc.

This blog is notepad cum share knowledge platform for all other reader who wish to be in touch that i know and follow it.