Passed RHCE

Hey guys, i returned to my blog after a long time. Now i have passed the RHCE exam on RHEL 6.0 with a score of 100% in RHCSA and 91% in RHCE

            Lot of thanks to all for following my blogs.

Read more...

EX442 System Monitoring and Performance Tuning Certificate of Expertise

Systems Monitoring and Performance Tuning

EX442 System Monitoring and Performance Tuning Certificate of Expertise

• use utilities such as vmstat,iostat,mpstat,sar, gnome-system-monitor, top and others to analyze and report system behavior
• configure systems to provide performance metrics over a network via SNMP
• query system performance metrics using SNMP
• configure graphical SNMP client utilities such as MRTG,RRDtool, etc.
• use the Pluggable Authentication Modules (PAM) mechanism to implement restrictions on critical system resources
• use /proc/sys, sysctl and /sys to examine and modify and set kernel run-time parameters
• use utilities such as dmesg, dmidecode, x86info, sysreport etc. to profile system hardware configurations
• analyze system and application behavior using tools such as ps, strace, top, OProfile and Valgrind
• configure systems to run SystemTap scripts
• alter process priorities of both new and existing processes
• configure systems to support alternate page sizes for applications that use large amounts of memory
• given multiple versions of applications that perform the same or similar tasks, choose which version of the application to run on a system based on its observed performance characteristics
• configure disk subsystems for optimal performance using mechanisms such as software RAID, swap partition placement, I/O scheduling algorithm selection, file system layout and others
• configure kernel behavior by altering module parameters
• calculate network buffer sizes based on known quantities such as bandwidth and round-trip time and set system buffer sizes based on those calculations

Read more...

Configure a High-Availability(HA) cluster using physical system

Port Number for the cluster
luci - 8084
ricci - 11111

Install luci and ricci on cluster nodes

[root@server1 ~]# yum install -y luci ricci


Initialize the luci
[root@server1 ~]# luci_admin init
Initializing the luci server


Creating the 'admin' user


Enter password:
Confirm password:


Please wait...
The admin password has been successfully set.
Generating SSL certificates...
The luci server has been successfully initialized


You must restart the luci server for changes to take effect.


Run "service luci restart" to do so


Start the luci service
[root@server1 ~]# service luci start
Starting luci: Generating https SSL certificates...  done             [  OK  ]


Point your web browser to https://server1.example.com:8084 to access luci


Open the firefox
[root@server1 ~]# firefox https://server1.example.com:8084 &


[root@server1 ~]# netstat -ntlp | grep 8084
tcp        0      0 0.0.0.0:8084                0.0.0.0:*                   LISTEN      11076/stunnel

Read more...

MySQL Checksum

This is another tool in the same toolkit as archiver. I just saw a great blog post on it athttp://blog.arabx.com.au/?p=883. Documentation can be found athttp://mysqltoolkit.sourceforge.net/doc/mysql-checksum-filter.html. This is an invaluable tool for ensuring your replicated tables are staying in sync, something that MySQL replication does not do. Tables will drift and if you are dealing with critical data for read support, reports or backups, this will prove invaluable.

This is referenced from the following site

Read more...

Nagios Plugins for Monitoring MySQL

You can come to know how to setup Nagios pluging for monitoring the mysql server by seeing this video and as well as pdf file

I am about to present the very first public appearance of PalominoDB's nagios plugin for MySQL.  This has been running on several clients in production for about 6 months, so we know it's stable.  The PDF's of the presentation slides and white papercan be downloaded, and are also available from our Community section (presentationsand white papers) in the menu bar at the top of each page.  Also you can download the code to use in your Nagios infrastructure.

The link of the pdf file. Please click here

Read more...

Login as root
# su -
# <Enter password>

open nagios configuration file
# vi /usr/local/nagios/etc/nagios.cfg

open your windows configuration file for editing
# vi /usr/local/nagios/etc/ojects/windows.cfg

###Enter insert mode and provide the monitored computer's IP address here###
###Host Definations###
define host {
use windows-server
host_name winserver
alias My Windows Server
address 192.168.91.2
}

Now exit and save this file
:wq

I have already downloaded "send_sms.sh" script into my desktop

I will copy "sms_send" script to the "libexec" folder
# cp /root/Desktop/sms_send.sh /usr/local/nagios/libexec

open your "commands config file for editing
# vi /usr/local/nagios/etc/objects/commands.cfg

Enter insert mode and type your command definations here
## ozeki's NG's 'notify-service-by-sms' command defination ##
define command{
command_name   notify-service-by-sms
command_line   /usr/local/nagios/libexec/sms_send.sh "--Nagios Service Notification --Host: $HOSTNAME$, State: $HOSTSTATE$, Service:$SERVICEDESC$, Description: $SERVICESTATE$, TIME:$LONGDATETIMES$"
}


## ozeki's NG's 'notify-host-by-sms' command defination ##
define command{
command_name   notify-host-by-sms
command_line   /usr/local/nagios/libexec/sms_send.sh "--Nagios Host Notification --Host: $HOSTNAME$, State: $HOSTSTATE$, TIME:$LONGDATETIMES$"
}

once it is done,exit and save your file
:wq

Open your "contacts" config file for editing
# vi /usr/local/nagios/etc/objects/contacts.cfg
## below the CONTACTS section edit the following ##
##Enter the notification command values for the contact##
define contact{
contact_name nagiosadmin;
use generic-contact;
alias Nagios Admin;
service_notification_commands   notify-service-by-sms
host_notification_commands   notify-host-by-sms
email nagios@localhost;
}


Onece it is done, exit and save your file.
:wq


To make changes come into force, restart Nagios service
# service nagios restart

Now you can start Nagios
# firefox http://localhost/nagios

Enter user name and password

click Host Group
click services
click criticals
As you can see there are already some problems with the monitored computer.

If you take a look at Ozeki NG - SMS Gateway you can see the sent message.
# firefox http://127.0.0.1:9501

Enter user name and password of SMS Gateway application

click admin
click sent
view the message have been sent.

For more information please visit Ozekisms site

Read more...

Windows Shared HP printer in Ubuntu / Debian Linux (using samba)

Most of the Computer Labs in Industry and Education Institutions are equipped with Windows. So Printers are also connected to Windows machines. Here a Simple howto for sharing windows shared printers for Linux users. I have test with a HP1015 printer installed in an Windows XP machine and shared. My linux box is ubuntu 9.04 ( I also tested with ubuntu 8.04, 8.10 , debian 4.0 and 5.0).

First install samba

apt-get install samba

apt-get install smbfs

apt-get install cupsys

after this installations

open a browser and type

http://localhost:631/

you will get a cups administration page

select add printer

then type Name : anything
Location : anything
description : anything

now you will get a dropdown menu

select windows printer via samba

now there is text box Device URI

type smb://shibuscomputer/1015 ( see I have a shared hp 1015 printer at computer name called shibuscomupter and share name of printer is 1015 with permision to all)

after selecting uri u will get a page for selecting make

select your printer make in my case it is HP

next page select model HP Laserjet series PCL 4/5 CUPS v 1.2 (en)now printer installation is over

you can make a test print now

Read more...

Famous Personalities of Computer Science

I am trying to collect photos of Famous Personalities of Computer Science.

Charles Babbage (Father of Computer)
Famous mathematician, philosopher, inventor and mechanical engineer who originated the concept of a programmable computer.













Blaise Pascal (Father of Programming Language)

French mathematician, physicist, and religious philosopher










Alan Turing ( Father of Computer Science)



Alan Turing was conceived in Chhatrapur, Orissa, India.[4] His father, Julius Mathison Turing, was a member of the Indian Civil Service. Read More Here






Gordon Moore ( Moor's Law)


Several measures of digital technology are improving at exponential rates related to Moore's law, including the size, cost, density and speed of components.








Claude E Shannon (Father of Information Theory)

Claude Elwood Shannon, the mathematician who laid the foundation of modern information theory while working at Bell Labs in the 1940s, died on Saturday. He was 84.

Read More Here






John Warner Backus ( Founder of FORTRAN)


John Warner Backus (December 3, 1924 – March 17, 2007) was an American computer scientist. He directed the team that invented the first widely used high-level programming language (FORTRAN) and was the inventor of the Backus-Naur form (BNF),
More

Read more...