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Some important thoughts for System Administrators

posted Aug 7, 2011, 6:34 PM by ahmad fauzi   [ updated Aug 7, 2011, 6:38 PM ]

  • Never do something you can't undo.
  • Always check the backups, never assume they are working. Make sure you can restore from them, too.
  • Write down what you did, even if you know you will never forget it, you will.
  • If you do it more than once, write a script.
  • Get to know your users before there is a problem, then when there is, they will know who you are and maybe have a little understanding.
  • Remember you are performing a service for your users, you don't own the system, you just get to play with it.
  • Check your backups.
  • Never stop learning, there is always something you should know to make your job easier and your system more stable and secure.
  • Check your backups, again.

System Administration Skills

posted Jul 28, 2011, 7:28 PM by ahmad fauzi   [ updated Aug 10, 2011, 2:32 AM ]

Are you SysAdmin
The duties of a system administrator are wide-ranging, and vary widely from one organization to another. Sysadmins are usually charged with installing, supporting, and maintaining servers or other computer systems, and planning for and responding to service outages and other problems.

Other duties may include scripting or light programming, project management for systems-related projects, supervising or training computer operators, and being the consultant for computer problems beyond the knowledge of technical support staff. To perform his or her job well, a system administrator must demonstrate a blend of technical skills and responsibility

System administration skills can be classified in four general levels. The links below discuss the required skills, desired skills, and responsibilities of each of those levels. Following the levels are some general thoughts on system administration in general.

Novice System Administrator:
  • Required skills:

    • Has strong inter-personal and communication skills: is capable of explaining simple procedures in writing or verbally; has good phone skills.
    • Is familiar with Unix and its commands/utilities at the user level. Can edit files using more than one editor. Uses at least two shells one of them being the Bourne shell.
    • Can perform standard file processing tasks; find, move, remove, redirection.

  • Required background:

    • Two years of college or equivalent post-high school education or experience.

  • Desirable:

    • A degree or certificat in computer science or related field.
    • Previous experience in customer support, computer operations, system administration, or another related area.
    • Motivated to advance in the profession.

  • Appropriate responsibilities:

    • Perform routine tasks under the direct supervision of a more experienced administrator.
    • Be the front-line interface for users; accepting problem reports and passing them to the appropriate system administrators.
    • Performs some security functions, especially monitoring the system


Junior System Administrator:

  • Required skills:

    • Has strong inter-personal and communication skills: capable of training users in applications and Unix fundamentals. Able to write basic system and user documentation.
    • High skill level with most Unix commands and utilities.
    • Familiar with most basic system administration tools and tasks. For example, can cleanly boot and shutdown the system, add and remove user accounts, use backup programs, perform fsck and maintain system database files (groups, hosts, aliases, etc.)
    • Fundamental understanding of the functioning of the Unix operating system: for example understands job control, hard and soft linking, the difference between shell programs and kernel programs.
    • Basic understanding of Unix security procedures

  • Required background:

    • One to three years of system administration experience.

  • Desirable:

    • Degree in CS or a related field.
    • Familiarity with networked/ distributed computing environments. For example: can use the route command, add a workstation to a network, or mount a remote filesystem.
    • Ability to write functional scripts in an administrative language (shell, Perl, Tk).
    • Some programming experience in an applicable language like C.

  • Appropriate Responsibilities:

    • Administer a small site alone, or assist in the administration of a larger site.
    • Work under the general supervision of a more senior system administrator or computer systems manager.
    • Perform normal security procedures, able to advise users on standard security protocol.


Intermediate/Advanced System Administrator

  • Required Skills

    • Has strong inter-personal and communication skills: capable of training users in complex topics, making presentations to internal groups. Able to write intricate system and user documentation. Capable of writing and explaining purchase justifications.
    • Independent problem solving; self-directed, self-starting.
    • Very comfortable with most aspects of the Unix operating system: paging/swapping, inter-process communication, devices and device driver fundamentals, file system concepts like inode and superblock.
    • Familiar with fundamental networking/distributed computing environments and concepts. Can configure NFS and NIS, use nslookup or research to check information in the DNS.
    • Ability to write detailed scripts in at least one, preferably two administrative lnaguages, (shell scripts, Perl, Tk).
    • Ability to perform at least minimal debugging and modification of C programs.
    • Ability to perform most security audits, and protect the system against intrusion.

  • Required Background:

    • Three to five years of system administration experience.

  • Desirable:

    • At least a BS in Computer Science or a related field.
    • Significant programming background in any applicable language.

  • Appropriate Responsibilities:

    • Receive general instructions for new duties from supervisor.
    • Administers a mid-size site alone, or assists in administration of a larger site.
    • Initiates some new responsibilities and helps plan for the future of the site and network.
    • Manages novice system administrators or operators.
    • Evaluates and/or recommends purchases; has strong influence on the purchasing process.
    • Serves as the first line of defense against intrusion and inadvertent system damage.


Senior System Administrator:

  • Required Skills

    • Strong inter-personal and communication skills; capable of writing proposals and papers, acting as a vendor liaison, making presentations to customer/client audiences or making professional presentations, work closely with upper management.
    • Ability to solve problems quickly and completely.
    • Ability to identify tasks which should be automated and then write tools to automate them.
    • Solid understanding of the Unix based operations system: understands paging and swapping, interprocess communication, devices and device drivers, can perform system analysis and tuning.
    • Ability to program in at least one, preferably two administrative languages, (shell, Perl, Tk) and port C programs from one platform to another, write small C programs.
    • Solid understanding of networking/distributed computing environments, understanding the principals of routing, client/server programming, and the design of consistent network-wide filesystems.

  • Required Background:

    • More than 5 years of previous system administration experience.

  • Desirable:

    • A degree in CS or a related field. Advanced degree preferred.
    • Extensive programming experience in an applicable language.
    • Publications within the field of system administration.

  • Appropriate Responsibilities:

    • Design/implement complex local and wide-area networks of machines.
    • Manages a large site or network.
    • Works under general direction of senior management.
    • Establishes/recommends policies and procedures for system use and services.
    • Provides the technical lead and/or supervision for system administrators, system programmers, or others.
    • Has purchasing authority and responsibility for purchase justification.

Bagaimana Merubah Kecepatan Kartu Jaringan di Ubuntu

posted Jul 27, 2011, 1:41 AM by ahmad fauzi   [ updated Aug 10, 2011, 2:33 AM ]

Jika anda ingin mengubah kecepatan dan duplex kartu jaringan, anda harus menggunakan ethtool atau mii-tool. ethtool dapat digunakan untuk query dan mengubah pengaturan seperti kecepatan, auto-negosiasi dan offload checksum pada banyak perangkat jaringan, perangkat terutama Ethernet.

Di ubuntu jika Anda ingin menggunakan mii-tool maka anda harus menginstal net-tools paket.

Net-paket alat termasuk alat penting untuk mengontrol subsistem jaringan dari kernel Linux. Ini termasuk arp, ifconfig, netstat, rarp, nameif dan rute. Selain itu, paket ini berisi utilitas yang berhubungan dengan jenis perangkat keras jaringan tertentu (plipconfig, slattach, mii-tool) dan aspek lanjutan darikonfigurasi IP (iptunnel, ipmaddr).

Dalam paket upstream 'hostname' dan turunannya yang disertakan. Mereka tidak diinstal oleh paket ini, sejak ada paket khusus "hostname *. deb".

Instal paket yang dibutuhkan

sudo apt-get install ethtool net-tools

Pertama, Anda perlu menemukan kartu jaringan kecepatan yang ada untuk ini Anda dapat menggunakan perintah berikut

eth0 ethtool

Setelah Anda mengetahui kecepatan saat ini dan rincian duplex, anda dapat mengubah menggunakan perintah berikut

Jika Anda ingin setup eth0 10 atau 100 atau 1000 kecepatan ethtool coba ini

sudo ethtool -s eth0 autoneg off speed 10 duplex half

sudo ethtool -s eth0 autoneg off speed 100 duplex full

sudo ethtool -s eth0 autoneg off speed 1000 duplex full

Jika Anda ingin membuatnya permanen Anda harus menambahkan baris berikut ke /etc/network/interfaces File

gksudo gedit /etc/network/interfaces

Tambahkan baris berikut

pre-up /usr/sbin/ethtool -s $IFACE autoneg off 100 duplex full

Simpan dan keluarlah dari file

Anda perlu restart layanan jaringan dengan menggunakan perintah berikut

sudo networking restart

comments


Session Manager Firefox Add-on

posted Jul 27, 2011, 1:26 AM by ahmad fauzi   [ updated Aug 10, 2011, 2:34 AM ]

Session Manager saves and restores the state of all or some windows - either when you want it or automatically at startup, after crashes or periodically. It can also automatically save the state of open windows individually.

This extension replaces SessionSaver and Tab Mix Plus’ session manager. It stores more data than both of them and should be more reliable in saving and restoring. Although it is not recommended to have more than one session related extension installed, Session Manager is compatible at least with Tab Mix Plus. It can import sessions from both SessionSaver and Tab Mix Plus.

Download Session Manager Firefox Add-on
You can download Download Session Manager Firefox Add-on from here

Setup Openfire Instant Messaging Server di CentOS 5.6

posted Jul 26, 2011, 8:24 PM by ahmad fauzi   [ updated Aug 10, 2011, 2:40 AM ]

Dalam dunia yang berubah saat ini, komunikasi terpadu, dukungan organisasi dan tim memerlukan beberapa bentuk komunikasi untuk meningkatkan efisiensi dan mungkin kepuasan pelanggan. 

Dalam dokumen ini, kita akan melihat cara men-setup server Instant Messaging pada CentOS 5.6 menggunakan server IM sumber bebas dan open berbasis XMPP. Untuk melanjutkan kita dapat mengatakan hal berikut tentang XMPP:

Extensible Messaging dan Presence Protocol (XMPP) merupakan open-standar protokol komunikasi untuk pesan-berorientasi middleware berbasispada XML [1]. Protokol awalnya bernama Jabber, [2] dan dikembangkan olehJabber terbuka (Extensible Markup Language) sumber komunitas pada tahun 1999 untuk, awalnya, dekat-real-time, extensible instant messaging (IM),informasi keberadaan, dan pemeliharaan daftar kontak. Dirancang untuk diperluas, protokol hari ini juga menemukan aplikasi dalam VoIP dan sinyaltransfer file.

Menurut igniterealtime.org, Openfire adalah sebuah kolaborasi real time (RTC) server berlisensi di bawah GPL Sumber Terbuka. Menggunakan protokol hanya terbuka yang banyak digunakan untuk instant messaging, XMPP (juga disebutJabber). Openfire menawarkan keamanan rock-solid dan kinerja.

Silakan mengunjungi ke http://www.igniterealtime.org/downloads/index.jsp dan download Openfire dengan mengklik tab Linux dan memilih versi rpm karena kita menjalankannya di CentOS. Kami juga akan men-download klien IM bebas yang dikembangkan oleh pengembang Openfire yaitu Spark. Pada halaman download, klik pada Linux dan pilih versi rpm atau klik pada tab Windows dan pilih versi exe dengan asumsi Anda memiliki lingkungan dual boot.



Instalasi OpenFire

Copy rpm file OpenFire dan jalankan perintah:

rpm -Uvh openfire-3.7.0-1.i386.rpm

Perintah ini akan menginstal Openfire yang akan terpasang pada port 9090. Sekarang buka web browser dan arahkan ke http:// {OpenFire_Server_IP: 9090} yang seharusnya membawa Anda ke layar instalasi. Ikuti semua pilihan default dan harus membawa Anda ke layar Login ditunjukkan di bawah ini:






Konfigurasi Spark Client

Ketika anda men-download klien Spark, instalasi bisa langsung dilakukan. Instalasi Openfire yang kita lakukan menerima pendaftaran siapa pun yang berarti bersifat terbuka, dapat mendaftar atau setup account.

Untuk mengkonfigurasi Klien Spark, cukup klik pada account dan isi berikut:

Username: Masukkan username yang diinginkan disini misalnya muffycompo
Password & Confirm Password: Masukan password yang Anda inginkan dan konfirmasi di sini misalnya h4rds3cr3t
Server: Masukan IP Anda di sini atau domain jika Anda menggunakan infrastruktur DNS





Cara Memasang Google Chat (GTalk) Di Website

posted Jul 26, 2011, 1:46 AM by ahmad fauzi   [ updated Jul 26, 2011, 2:35 AM ]

Ada banyak aplikasi messenger yang saat ini digunakan, beberapa diantaranya seperti Yahoo Messenger, Facebook dan GTalk.

GTalk yang merupakan produk dari Google bisa digunakan dengan aplikasi GTalk ataupun dengan email client dari Google seperti Gmail maupun Google Apps Mail.

Untuk mengoptimalkan sarana Google Chat, GTalk bisa juga dipasang di website sebagai media kontak.

Script GTalk/Google chat untuk website bisa diambil di http://www.google.com/talk/service/badge/New (harus login gmail dahulu tentunya).
Untuk merubah tampilan maupun nickname, bisa diklik Link Edit seperti pada gambar dibawah.

   Chat with Ahmad Fauzi    



Edit▲   Disable old badges


Title (optional): 
Your nickname:   (as displayed to guests)
Style:      
 Show your status message


Untuk menggunakan lencana ini, salin teks di bawah dan paste kehalaman web atau pesan email. Jika Anda ingin memasukkan lencana Anda dalam pesan email, Anda harus menggunakan type 'Hyperlink hanya' atau 'Url hanya'. Anda juga dapat menyalin dan menyisipkan kode HTML di bawah ini ke halaman Anda jika editor atau situs yang host halaman web Anda mendukung langsung mengedit HTML.

<img height="14" width="16" style="padding:0 2px 0 0;margin:0;border:none" src="http://www.google.com/talk/service/resources/chaticon.gif" alt=""><img height="9" width="9" style="padding:0 2px 0 0;margin:0;border:none" src="http://www.google.com/talk/service/badge/Show?tk=z01q6amlqf2sugojvn23g3pa9b21ipb8sdob74onfe4j7h5sucvjvtm551cetdg9m5b9moobcs8k8hsgauhd7jq5kuivvpeo8r1aquqjeqjd3dhhiqpishurrcndm4btdntmpatr32kmcbjvd3lncg9ttgbj4qep3b7pop6bv&amp;w=9&amp;h=9" alt=""><a href="http://www.google.com/talk/service/badge/Start?tk=z01q6amlqf2sugojvn23g3pa9b21ipb8sdob74onfe4j7h5sucvjvtm551cetdg9m5b9moobcs8k8hsgauhd7jq5kuivvpeo8r1aquqjeqjd3dhhiqpishurrcndm4btdntmpatr32kmcbjvd3lncg9ttgbj4qep3b7pop6bv" target="_blank" title="Click here to chat with Ahmad Fauzi">Chat with Ahmad Fauzi</a>

Installing Apache2 With PHP5 And MySQL Support On OpenSUSE 11.4 (LAMP) - Page 2

posted Jul 25, 2011, 7:54 PM by ahmad fauzi   [ updated Jul 26, 2011, 12:50 AM ]

Testing PHP5

The document root of the default web site is /srv/www/htdocs/. We will now create a small PHP file (info.php) in that directory and call it in a browser. 

The file will display lots of useful details about our PHP installation, such as the installed PHP version.

vi /srv/www/htdocs/info.php

<?php
phpinfo();
?>
(If you get the message You do not have a valid vim binary package installed. Please install either "vim", "vim-enhanced" or "gvim"., please run
yast2 -i vim
to install vi and try again. )

Now we call that file in a browser (e.g. http://192.168.0.100/info.php):


As you see, PHP5 is working, and it's working through the Apache 2.0 Handler, as shown in the Server API line. If you scroll further down, you will see all modules that are already enabled in PHP5. MySQL is not listed there which means we don't have MySQL support in PHP5 yet.

Getting MySQL Support in PHP5

To get MySQL support in PHP, we can install the php5-mysql package. It's a good idea to install some other PHP5 modules as well as you might need them for your applications:

yast2 -i php5-mysql php5-bcmath php5-bz2 php5-calendar php5-ctype php5-curl php5-dom php5-ftp php5-gd php5-gettext php5-gmp php5-iconv php5-imap php5-ldap php5-mbstring php5-mcrypt php5-odbc php5-openssl php5-pcntl php5-pgsql php5-posix php5-shmop php5-snmp php5-soap php5-sockets php5-sqlite php5-sysvsem php5-tokenizer php5-wddx php5-xmlrpc php5-xsl php5-zlib php5-exif php5-fastcgi php5-pear php5-sysvmsg php5-sysvshm

Now restart Apache2:

/etc/init.d/apache2 restart

Now reload http://192.168.0.100/info.php in your browser and scroll down to the modules section again. You should now find lots of new modules there, including the MySQL module:

Installing Apache2 With PHP5 And MySQL Support On OpenSUSE 11.4 (LAMP) - Page 1

posted Jul 25, 2011, 7:43 PM by ahmad fauzi   [ updated Jul 26, 2011, 6:06 PM ]

Preliminary
In this tutorial I use the hostname server1.example.com with the IP address 192.168.0.100. These settings might differ for you, so you have to replace them where appropriate.

Installing MySQL 5

First we install MySQL 5 like this:

yast2 -i mysql mysql-client mysql-community-server

Then we create the system startup links for MySQL (so that MySQL starts automatically whenever the system boots) and start the MySQL server:

chkconfig -f --add mysql
/etc/init.d/mysql start

To secure the MySQL installation, run:

mysql_secure_installation

Now you will be asked several questions:

server1:~ # mysql_secure_installation


NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MySQL
      SERVERS IN PRODUCTION USE!  PLEASE READ EACH STEP CAREFULLY!

In order to log into MySQL to secure it, we'll need the current
password for the root user.  If you've just installed MySQL, and
you haven't set the root password yet, the password will be blank,
so you should just press enter here.

Enter current password for root (enter for none):
 <-- ENTER
OK, successfully used password, moving on...

Setting the root password ensures that nobody can log into the MySQL
root user without the proper authorisation.

Set root password? [Y/n]
 <-- Y
New password: <-- fill in your desired MySQL root password
Re-enter new password: <-- confirm that password
Password updated successfully!
Reloading privilege tables..
 ... Success!

By default, a MySQL installation has an anonymous user, allowing anyone
to log into MySQL without having to have a user account created for
them.  This is intended only for testing, and to make the installation
go a bit smoother.  You should remove them before moving into a
production environment.

Remove anonymous users? [Y/n]
 <-- Y
 ... Success!

Normally, root should only be allowed to connect from 'localhost'.  This
ensures that someone cannot guess at the root password from the network.

Disallow root login remotely? [Y/n]
 <-- Y
 ... Success!

By default, MySQL comes with a database named 'test' that anyone can
access.  This is also intended only for testing, and should be removed
before moving into a production environment.

Remove test database and access to it? [Y/n]
 <-- Y
 - Dropping test database...
 ... Success!
 - Removing privileges on test database...
 ... Success!

Reloading the privilege tables will ensure that all changes made so far
will take effect immediately.

Reload privilege tables now? [Y/n]
 <-- Y
 ... Success!

Cleaning up...


All done!  If you've completed all of the above steps, your MySQL
installation should now be secure.

Thanks for using MySQL!

server1:~ #

Now your MySQL setup should be secured. 

Installing Apache

Apache2 is available as an OpenSUSE package, therefore we can install it like this:

yast2 -i apache2

Now configure your system to start Apache at boot time...

chkconfig -f --add apache2

... and start Apache:

/etc/init.d/apache2 start

Now direct your browser to http://192.168.0.100, and you should see the Apache2 placeholder page (don't worry about the 403 error, this happens because there's no index file (e.g. index.html) in the document root directory):

Apache's default document root is /srv/www/htdocs/ on OpenSUSE, and the configuration file is /etc/apache2/httpd.conf. Additional configurations are stored in the /etc/apache2/conf.d/ directory.

Installing PHP5

We can install PHP5 and the Apache PHP5 module as follows:

yast2 -i apache2-mod_php5

We must restart Apache afterwards:

/etc/init.d/apache2 restart

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