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Slackware Linux

Dear readers,

It's obvious thing to say that I really like Slackware Linux. Why? that's because of its stablity and simplicity. You know KISS? Keep It Simple Stupid!. You want to know Linux, learn Slackware. You want to get headache, you learn Slackware. :D . But once you master it, nothing beats it. For rock-solid stability of Linux, I gotta switch to Slackware. Mandrake could not fit the requirement. It has something to do with apic thing that got conflict with power management feature. This results in a hanging server . The solution always to hard reboot (by pressing the reset button). Don't get me wrong. Mandrake is a good distribution too but sometimes it contains unnecessary bells and whistles. For some reasons, it fails to run properly on certain machines.

To fix this problem (and after it gave me a lot of headaches and stomachache :P), I gave Slackware a go. Now after 3 days, I never notice a single hang and no slow whatsoever. This brings to happy users and the most…

Mannheim - The Open Source city

The technology decision makers have already moved the majority of Mannheim's 120 servers to the open-source operating system. Next, they plan to shift its 3,500 desktops to the open-source productivity application OpenOffice.org, running on Linux. The migration should help the city with its aim of using programs that support open standards, which can be used by any software, whether closed source or open source. Some U.S. states--notably Massachusetts and local and national governments have been embracing standard file formats such as the OpenDocument format used by OpenOffice, a move that ensures that public documents won't be beholden to a particular proprietary program.
"We want to decide our IT strategy in Mannheim, and not have Microsoft make the decision for Mannheim," said Gerd Armbruster, the IT infrastructure manager at the German city.

"We want to decide our IT strategy in Mannheim, and not have Microsoft make the decision for Mannheim."

The city…

dbmail - How to

First of all I would like to share with you all my experience setting up a *testing* mailserver using dbmail as the imap and postfix as the smtp server and of course on Linux. This time I used Slackware Linux 10.2 and this server is actually behind a firewall. For overview what is dbmail, please visit dbmail.org or read previous posting.

Requirements
You need all of these:

mysql server ( I used 4.1.14. This version supports InnoDB)*
dbmail package ( i used version 2.0.7 )Postfix ( I used version 2.2.7 )DBMail source (get the latest from dbmail.org)
* Since some DBMail tables can get VERY large (depending on your mailusage) we advise using InnoDB as database storage backend.

Let's get dirty!
Make sure mysql is running. First you'll need to create the DBMail database in MYSQL. You can do this by issueing the following command. This step is only necessary when you do not have a database for DBMail yet. Note that you will be prompted for the MySQL root password.

mysqladmin create…

dbmail - The high performance mail server

DBMail is a mail system that stores mails into a database including attachments. I really like this idea when I first read about it on the net. The first thing came into my mind was speed. Traditional filesystem can't beat the speed of SQL query especially when we deal with thousands of users accessing millions of mails. That said, the time of retrieving, storing and searching of mails can be reduced significantly. One system that can compete with this is Cyrus. Cyrus is also conceptually the same as DBMail but it uses different database backend.

I am now struggling setting up my mail server based on DBMail and I use SquirrelMail as the frontend to login and access mails. Things go wrong somewhere and it's been 2 days now. I just can't receive mails for now. Login works ok. I hope I can complete it by next week.

Don't you think learning new technology is fun?

How to setup USB Scroll Mouse in Linux

This is my experience in setting up my mouse (USB, scroll mouse) in my new SlackwareLinux box. On standard installation, Slack installer did a good job of detecting my USB mouse but did not properly configure it for the scroll wheel. So, I just couldn't use the wheel to scroll down. On my Mandrake system, it did detect my USB mouse and the configured the scroll wheel automagically. This is what I need to add in my /etc/X11/xorg.conf in inputdevice section:

option "Protocol" "IMPS/2"
option "ZAxisMapping" "4 5"
option "Buttons" "5"

Make sure the Protocol is IMPS/2 because protocol PS/2 does not support scroll wheel. Happy scrolling!...

Gmail now with antivirus scanner

Gmail just launched its new feature for gmail users : virus scanner for attachment. The feature works this way:
Each time we send and receive attachments , gmail will scan them for viruses.If it is found in an attachment we've received, the system will attempt to remove it, or clean the file, so we can still access the information it contains.
If the virus can't be removed from the file, we won't be able to download it.If a virus is found in an attachment we're trying to send, we won't be able to send the message until we remove the attachment.Although I never encountered any viruses attached to emails sent to my gmail's account (maybe they were running some sort of virus scanner before to filter attachments to /dev/null :) ), I still think this is important feature for gmail's users because some users don't know that their files has been infected by virus(es) and then they send it to their friends without knowing it.

WiMax - The next generation of wireless technology

Wireless techology has become common these days. In Malaysia, ISPs has been introducing this technlogy for many years now. TMNet's HotSpot, JARING's wireless broadband and TIME's webbit and TIMEZONE. I've never bother about this technology since I don't have the equipment and i don't involve in setting up one. But when my company decided to buy ISDN line (one year ago before changing back to TMNet's Streamyx), the vendor gave us a free wireless access point (AP). Then, my involvement in setting up and learning this technology began. The most important point for me was "to get the idea how it works, know the system and how to implement it" . Then I realized many things and threw lots of "000000 I see" words. :)

Recently I've read about WiFi technology and its history. Many people think that wireless is WiFi. This is not true. There are many types of wireless network connection. Commonly used are :
802.11a (speed - 54 Mbps, FQ band - 5…

Firefox 1.5 released

Firefox 1.5 has been released after the 1-year wait from the last major software update, Firefox 1.0. It sports a new rendering engine (Gecko 1.8) as well as hundreds of other software improvements. Important changes include faster page loading, the ability to reorder tabs, faster back and forward buttons, a feature to clear personal data, improved accessibility and popup blocking, and SVG, CSS 2 and CSS 3, and JavaScript 1.6 support. You can download it here.

Firefox has attracted attention as an alternative to other browsers such as MicrosoftInternet Explorer. As of September 2005, estimates suggest that Firefox's usage share is around 7.6% of overall browser usage (see market adoption section). Since its release, Firefox has slightly reduced Internet Explorer's dominant usage share.

It's raining cats and dogs

It's monsoon season here in East Coast of Peninsular Malaysia. When I'm thinking of rain, I'm thinking of an idiom it's raining cats and dogs to describe heavy rain. What I'm thinking was (at that time) , a group of cats and dogs, quarelling while they were falling off the roof. Funny isn't it? Well idioms are full of funny (and crazy?) synonyms but not all of them. I heard one of them since my secondary school years, hustle bustle. Then, my teacher said "It's too english for you!". All of us didn't get the correct answer for that particular fill in the blank question. Oh well. Now as a worker talking and writing in English for most part of my work, I still rarely use lots of them.

I can't take my eyes off you (relax a bit)

Nor yet were you seen
neither seen nor heard
when this earth was made
when the sky was built...

- Kalevala 3:245-248

He looked up as he plodded
Down 42nd Street,
So many nameless faces
All shuffling to some beat.

So many anonymities,
But then, to his surprise,
He suddenly made contact
With a pair of hazel eyes.

She looked into his soul's windows
And didn't look away.
A wry smile grew inside his mind;
"All right," he thought, "I'll play."

He gazed back at her placidly,
His cold blue eyes grew warm.
And only then did he glance down
To admire her female form.

As she passed him by that day,
He hazarded a grin.
She kept her lovely eyes on his
But still,
to his chagrin,
The woman walked away from him,
Without reciprocating.

He chuckled silently,
knowing
That other eyes were waiting.


-- courtesy : AndersenSilva.com

Linux Advanced Routing And Traffic Control (LARTC)

Introduction
Networking in Linux is one of essential part for the success of this operating system. The flexibility and robustness are the key point for the success. However, the user-friendliness, at the very early stage, was not good which resembles the old Unix. Nowadays, many modern Linux distros come with good interface on setting up many aspects of networking stuff and many things can be configured automatically when the hardwares detected.
Many organizations need to have an advanced routing for their network infrastructure. Basic network infra cannot cope with certain conditions. This is when the advanced routing comes into play. In Linux, we have iproute2 package to work hand-in-hand with iptables and recent kernel for advanced routing. This topic is thoroughly covered on LARTC home page at http://www.lartc.org. My article here just covers basic things.
Make it work

Let's take a look at this scenario :

Scenario 1

We want to route packets that come from local network(s) to two…

How to make your mailserver faster ?

My mailserver was very slow when more than 10 users accessing it simultaneously. It uses squirrelmail as the front-end for webmail. As you know (or maybe don't know :P), squirrelmail is built using php and an administrator can extend its functionality via plugins. There's many good plugins to ease administrator's chore and also for users. php on a good side is a very powerful language but it is suffer when it has to open and execute many files. It has to recompile everytime the file is to be executed. This results in slower response because it has to do the same thing over and over again. But thank god I just found the solution. The solution is simple. Everytime the php file is compiled, the resulting binary is used whenever the file is fetched. This results in faster execution time and faster response. The term for this solution is php accelerator. There's many php accelerator out there but the one that gives large boost performance is eaccelerator formerly know as Tu…

Merdeka day celebration

Cherating -- 2 days before National Day.

31st August every year, Malaysian celebrates "Merdeka Day" or National Day. On National Day eve, I was still at my office doing my work. repairing..downloading.. configuring..installing and testing. What a day for me. Never knew to rest at home or joining my friends celebrating the Merdeka Day. Not that I hadn't had a clue or had experience to celebrate it but I just didn't give a damn. Why? because I prefered to celebrate it in cyber world. Wired and sometimes wireless.

I had experienced it before. During my study years at Penang. Those days were unforgettable. We gathered at a field near Padang Kota Lama and waiting for the countdown. 10..9..8....3..2..1 and firework started. What did we get from a celebration like this? Is this the best way to celebrate? Many people complaining about the raising of oil price and many suffers from it. How can we waste money for the firework? Whose money is that? Can you tell me?

Ethernet bonding revisited

Ethernet bonding

2 days ago I was able to do ethernet bonding for my Linux box which acts as a proxy server and firewall. What I did was to bond two private network interfaces to act as one. What I need to do was installing 2 NICs and setting the driver (autodetect on modern distros). Then I need to create the bonding interface like this :
~#modprobe bonding mode=0 miimon=100~#ifconfig bond0 192.168.0.2 netmask 255.255.255.0 up~#ifenslave bond0 eth0~#ifenslave bond0 eth1Note:bond0 is the "bond" interface. eth0 and eth1 are the interfaces to be bonded so called slave devices (or interfaces).They are connected to my private network (LAN). The bond interface will have MAC address of the first slave device to be its MAC address. Please take note that the mode=0 means that we want load-balancing capability. You can use this bond interface in iptables command or tcpdump. In my network environment, I use this command to the bond0 interface:~#iptables -t nat -A PREROUTING -s 192.168.0…

Monday sickness, chatting, Xandross

If today is not Monday, I would have been in Pangkor ... swimming..



Today is Monday 15 August 2005. At 8.30 AM this morning I was still at my home preparing for work. Last night, I was happily playing with my student's laptop by installing Linux, did some modification to KDE theme and testing Codeweaver's CrossOver. My life was not connected for the whole Sunday. Why? My hand phone was broken (again?) and I have to send it to my friend's shop (again?). He laughed at me and offered me a better handphone as a replacement but for RM50. I said "Thanks but no thanks".

My life has changed since I knew how to chat. I have always thought that chatting is a waste of time. Actually I just forgot that I have to think the good side of it and get rid of the bad. I never liked chatting as i did now. My life was complete i guess since communication over internet primarily by exchanging emails and via forums. Now I feel incomplete without double-clicking on the Yahoo! Messenger wh…

Setting up transparent proxy server

Hi all,

Today, while setting up ip for my internal network, i found out that i have run out of IPs and the internet access was very slow. I ran into a situation called "bottleneck". A situation where a road becomes narrow with heavy traffic. How to speed up this? The answer is proxy server.

On with the theory
Proxy server is a server that can cache visited web pages. Dynamic web pages are not cached. When a client access a website, the proxy server , on behalf of the client access the website and cache it. the next the client or other client wants to connect to the site, the proxy server just give the cached site to the client. Thus reducing the response time from the actual site.

Transparent proxy
In a normal proxy case, you have to set manually for each client to connect to outside. It is not a practical solution if you have a lot of workstations + many apps to connect to the internet. What is more practical solution? The answer is "transparent proxy" and now iptables…

Setting up virus scanner for mail server

This task is quite simple and the tools are readily available on the internet. In the spirit of Open Source, may of the tools are made free and come with source code. Binary version for may distros are available too. It's only a matter of choice and how we're going to set things up.

Antivirus
Clam antivirus is one of the best antiviri around. So far she can detect almost 97% of Windows viri and worms. Those viri are always reached our computers over network and internet. The main medium is email. I personally got in average 5 to 10 emails containing virus. That's why, antivirus is really important these days.

Trashscan
This is a script invoked by procmail to scan and send a notice to the sender if the mail contains virus. trasscan comes with clamav package.

Setting up procmailrc for scanning

#
# procmail configuration for TrashScan:
# ZapCoded by Trashware; 13.10.2002
#

# [ ... ]

# ----------------------------------------------------------------------------- #
# Virus scan section ...…

Setting up Spam Detection System for mail server

For over a month, I did a research on how to install, configure and test spam detection system on mail server which i manage. Here's the quick step :

1. Install spamassassin from spamassassin.org. I use spamc and spamd and not the perl version. Advantage: faster for bz server.

2. Make this setting in /etc/mail/spamassassin/local.conf



# SpamAssassin user preferences file.
# See 'man Mail::SpamAssassin::Conf' for
# details of what can be tweaked.

# score needed to deem an email to be spam.
# the lower the score, the more likely the email
# will be classified as spam. default is 5, but
# I have found that 4 works a little bit better
required_hits 4

# if you find an email from an address classified
# as spam that should
# *never* be classified as spam, add it to the whitelist
whitelist_from *@mp3.com

# if you receive an email from an address that will
# always be spam, add it to the blacklist (comma separated)
blacklist_from big@boss.com

# Whitelist and blacklist addresses are now
# file-glob-…

Internet is ready

yesterday i managed to move the servers from old building to the new building. here are the pics just taken before I wrote this blog.

Technician Room


Computers are ready to be serviced!

No network huh?

Since 2 weeks ago, the new building was waiting for me to put all my stuff there but I just couldn't. Why? because the internet is not there yet. How can I work without it? My work needs an internet connection. So what should I do? Not moving!. and it is worth cause the UITM registration tomorrow needs internet connection to register the new students online. If I did move, I have to carry all the servers and routers and swtches to the old building. Actually I was waiting for TMNet personal to call me about the line at the new building yesterday but no one call.

Now I'm at office chatting and sms'ing my friend. One is my ex-student and the other one is my chatting friend. Network at the new building is still not complete yet. Lab 1 and 2 will be completed in a day or 2. I can't wait to keep my hands dirty configuring and troubleshhoting the new network. I noticed yesterday that the new switches were all 3com.

Busy day 2

Huh? I can't install Oracle free edition in lab? Yeah it's true coz it will break the policy. Now I understand. Dr. Janet instructed me not to do it. But the student can install it at home. She wanted to discuss this issue further with her colleagues back in Australia on how to get Oracle free or with discounted price for educational institution. She said that Oracle Malaysia is nasty. huh?

Day 2 meeting revolved around various subjects will be taught and softwares required. I was surprised to hear that for Computer Graphics subject, Java Swing Package will be used throughout the course. Students are expected to develop Computer Graphics applications with it. I have learned it for quite some time and it is quite difficult. They have to remember many Swing APIs and the RAM should be higher than 256 MB to run it smoothly as Java programs will chew up your memory in an instant.

A busy day for a lazy man

Today is so full of meeting from nine to 5. meeting packed day. I have a meeting with Flinders University regarding courses ShahPutra want to offered here. They have strict requirements regarding students intake, softwares and technology that we have here. "We are very Java" - said Dr. Janet, the IT Head The course will be offered is Bac. Of Comp. Sc And IT. I, as an system administrator should provide them with softwares required to run the program such as Java, C/C++, A web server (Apache), JDK 1.4, J2EE, Linux OS, Oracle and also MySQL. Thank god I can download the free edition of Oracle on Oracle website. That will save cost as our boss like. Students can run Oracle server on their own PCs and do their work.

Last night I read the RAID manual for the 10th times. I realized that for RAID 5, I should make RAID 1 first and booting can be done from it. I have three disks that I could make RAID 5. It is no automatic process for this as many installers do not support configuring…

Williams F1 gives green light to Linux

HP Linux supercomputer aids aerodynamics modelling for team cars
Peter Williams, vnunet.com 02 Oct 2003

The BMW Williams Formula 1 (F1) team has dramatically improved its high-resolution aerodynamic modelling of team cars by introducing an HP Linux supercomputer cluster.

The company, which currently lies second in this year's F1 Constructors' Championship, has added "several hundred" HP ProLiant Intel-based servers to its Oxfordshire headquarters.

Apart from driver skill, competitive advantage can be achieved through tyres, engine power, chassis and aerodynamics, with the latter the most difficult to control.

"Last year showed us that our chassis was a model of reliability but that there's still room for improvement, particularly on the aerodynamic front," said Patrick Head, technical director at Williams.

"[This] has given us the necessary technological leadership and expertise to design the revolutionary FW25 [this year's F1 car] rather than a modi…

Linux revs up Renault F1 testing

Linux revs up Renault F1 testing

IBM e1350 Linux cluster cuts simulation time from three weeks to 18 hours
Robert Jaques, vnunet.com 15 Mar 2005

Linux has helped the Renault Formula 1 team to slash its engine and chassis computational analysis time by 90 per cent.

The team dramatically cut the time it spends performing computational analysis, and ultimately reduced development costs, by deploying an IBM e1350 cluster running Linux. The system is based on IBM eServer e325 and e326 servers with AMD Opteron processors.

In addition, Renault Formula 1 has deployed two IBM eServer pSeries 630s running AIX, and one TotalStorage DS 4300 storage server, to capture and store the computational data generated by the e1350 cluster.

Christophe Verdier, Renault F1 Team IT director, said: "The performance of this system has enabled Renault F1 to fully optimise its V10 engine capability. This has given the team a considerable advantage, since a race is as much won in the factory as it is on the track.

&…

Firefox Browser Adoption Rates Slow

Open-source Web browser Firefox is continuing its spread across Europe, although the pace of adoption has slowed somewhat, according to a recently released report. French Web metrics company XiTi noted that Firefox now accounts for about 14 percent of browsers in Europe, up from 13 percent in April and 11 percent in March. The numbers fall in line with U.S. usage, which is approximately 13 percent. Finland shows the largest Firefox use, with over 30 percent of Web users employing the browser. The country is followed by Germany, with over 24 percent, and Hungary, with about 22 percent. At the bottom of the adoption list were Luxembourg, with 10 percent, Lithuania, at 7 percent, and Monaco, with 6 percent.

Slow Down
Mirroring a trend seen in the U.S., Europe's Firefox adoption rate appears to be slowing. Analysts point to several possible factors for the trend, including recent security flaws involving cross-site scripting and remote system access vulnerabilities. The flaws were rated…

RAID - Revisited

I'm still researching about RAID. I have done software RAID before and am looking for some hints on hardware RAID and the advantageous over software-based RAID. Let's get some basic picture of RAID and beyond.

What does RAID stands for ?
In 1987, Patterson, Gibson and Katz at the University of California Berkeley, published a paper entitled "A Case for Redundant Arrays of Inexpensive Disks (RAID)" . This paper described various types of disk arrays, referred to by the acronym RAID. The basic idea of RAID was to combine multiple small, inexpensive disk drives into an array of disk drives which yields performance exceeding that of a Single Large Expensive Drive (SLED). Additionally, this array of drives appears to the computer as a single logical storage unit or drive.

The Mean Time Between Failure (MTBF) of the array will be equal to the MTBF of an individual drive, divided by the number of drives in the array. Because of this, the MTBF of an array of drives would be to…

RSS

If you are lazy to update your website, there's an alternative to it. It is called RSS feeder. With it, you have no need to update your website with latest news from other sites. If the sites provide RSS, you can feed your website with their news with RSS feeder and it's done automatically. But before that, you should know how to setup one. There are many RSS feeders in the market and I personally use MagPieRSS.

Add RSS feeds to your Web site using MagpieRSS
Syndication of material from other sites is a good way to get fresh content on your site. As visitors arrive at your site they can see a teaser for the syndicated content and a link to the publisher. If they are interested in an item they can follow the link to the original location. You can add syndicated content to your site using the Really Simple Syndication (RSS) protocol and a bit of PHP code in the form of an application called MagpieRSS. Here's how.

MagpieRSS is an RSS parser written in PHP. It supports RSS 0.9 a…

Do your softwares suit your business or are you trying to fit your business to your softwares?

When I was reading Linux Format magazine yesterday, I came across this statement of an advertisement. This mag is hard to find in Kuantan (only at a bookshop in MegaMall which I think I'm the only one who buy it :) ). Other mags I have on my bookshelf is Linux Users And Developers and Linux Magazine which my friend sent me from London. Thanks Mark.

It's good to read Linux mags every night before going to bed. You will fall asleep when you start reading it. :-)

What it takes to be a system administrator?

I found this interesting article "What it takes to be a system admin?". I'm interested to know how exactly the work system admin is due to the fact that I have no formal training in this field, I think I should make an effort to be one. Like ones say, "experience is the best teacher". No one shouldn't agree with this statement. This is why we need practice (a lot). During the practice, we will encounter mistakes. With that, you'll know what's the best, what's good and what's bad and what's the worst thing to do.

Let's take a look at the key points of being a system administrator:

Change your mindset -- The true SA is a combination caretaker, security guard, and baby sitterLearn new toolsets -- If one wants to move into the corporate arena, then you must be able to take whatever tools are laying around and get the job done. This means the ability to learn new tools and to use old tools in new ways. Learn to handle pressure -- Expect to …

What is ethernet bonding?

In the new building, there will be 3 lines of broadband connection to the internet. I am thinking to make 'bonding' or port-trunking (cisco term) in order to provide load balancing and fault-tolerance connection. I have done this for dialup lines a few years ago. But this one is for ethernet. Every modern kernel supports this feature. Now let's take a look at what bonding is all about...

What is bonding?
Bonding is the same as port trunking. In the following I will use the word bonding because practically we will bond interfaces as one.

#!/bin/bash

modprobe bonding mode=0 miimon=100 # load bonding module

ifconfig eth0 down # putting down the eth0 interface
ifconfig eth1 down # putting down the eth1 interface

ifconfig bond0 hw ether 00:11:22:33:44:55 # changing the MAC address of the bond0 interface
ifconfig bond0 192.168.55.55 up # to set ethX interfaces as slave the bond0 must have an ip.

ifenslave bond0 eth0 # putting the eth0 interface in the slave mod for bond0
ifenslave bond0 …

The modem is broken

Today found out that the modem at my workplace broke. I have to contact TMNet to replace it coz it's still under warranty. Thank god, the replacement is a snap. Tomorrow, staff can connect to the internet.

I'm a system admin.

Me, MySelf And I

After being a system admin for 4 months, i think that this is my dream job but the pay is still not enough for me. I've learnt so many things about Linux and how to maintain them (I have 3 servers that i have to monitor). May things on my mind ranging from backup (the hardest if u want to transfer accounts from one server to another server.), tcp/ip, network design, firewall (this is fun!), routing config and etc.