New Hosting Karma!

The Perfect Linux Firewall Part I -- IPCop | HowtoForge - Linux Howtos and Tutorials

2006-08-14T22:01:00.000+07:00

The Perfect Linux Firewall Part I -- IPCop | HowtoForge - Linux Howtos and Tutorials: "This document describes how to install the GNU/Linux GPL IPCop firewall and create a small home office network. In the second installment we cover creating a DMZ for hosting your own web server or mail server and the Copfilter proxy for filtering web and email traffic. "

Zimbra on gentoo at Elfenbeinturm.cc

2006-07-29T16:38:00.000+07:00

Zimbra on gentoo at Elfenbeinturm.cc
Zimbra is a collaboration suite which includes an ajax based webmailer with an address book and calendar. It uses many popular open source components like postfix, openldap, spamassasin, apache and tomcat. Because its an integrated solution, installing on gentoo is not easy. But the author of this doc shows how to run Zimbra debian package under Gentoo's chroot.

Gentoo Linux Documentation -- Upgrading Apache (have you done it?)

2006-06-19T16:41:00.000+07:00

Gentoo Linux Documentation -- Upgrading Apache:
then Upgrading PHP
and making the server serves both PHP4 and PHP5

GCC upgrade guide

Hercules Load Balancer Virtual ApplianceVMTN Virtual Appliances Directory

2006-06-12T23:59:00.000+07:00

Hercules Load Balancer Virtual ApplianceVMTN

Hercules Load Balancer Virtual Appliance

Hercules is a tiny but mighty load balancer appliance. It can be used to balance requests using any of these TCP protocols:

HTTP
HTTPS
SMTP
FTP
POP3
LDAP

It runs on a linux os built from scratch to have a minimal
footprint. It can run with just 32MB memory for normal usage and you can increase memory requirements for the appliance as you need. It also has a built in web server, ssh server, dhcp client. You can administer the machine remotely via ssh. It is setup for dhcp so the networking is setup automatically. A webserver is installed to both serve up this page and to help you test different configurations. The load balancing functionality is provided by the excellent open source project pen.

[Note: VERY simple!!! - pizzaman]

Pound and Pen - Simple Load Balancing

2006-06-12T23:49:00.000+07:00

Pound and Pen - Simple Load Balancing: "Pound and Pen are simple web server load balancers licensed under the GPL that run mainly on Unix based operating systems. Pound is a web (port 80) load balancer only, unlike Pen which is designed to balance any simple TCP/IP protocol, including http, smtp, ftp, and others. Before you decide to load balance your website with one of these software programs there are several other considerations you may want to understand."
...
Pen Load Balancer - http://siag.nu/pen/
Pound Load Balancer - http://www.apsis.ch/pound/
...

Extracting remote_ip is easily done with mod_extract_forwarded
Pound mailing list has this information.
Or this one is good, with mod_rpaf.

Backup using SystemRescueCD & Partimage

2006-06-12T23:24:00.000+07:00

Partimage Partition Image is a Linux/UNIX utility which saves partitions in many formats (see below) to an image file.

SystemRescueCd is a linux system on a bootable cdrom for repairing your system and your data after a crash. It also aims to provide an easy way to carry out admin tasks on your computer, such as creating and editing the partitions of the hard disk. It contains a lot of system utilities (parted, partimage, fstools, ...) and basic ones (editors, midnight commander, network tools). It aims to be very easy to use: just boot from the cdrom, and you can do everything. The kernel of the system supports most important file systems (ext2/ext3, reiserfs, reiser4, xfs, jfs, vfat, ntfs, iso9660), and network ones (samba and nfs).

Today's the day

2006-05-31T22:27:00.000+07:00

Today's also the first day that I've ever linked to this site. The first link to this site comes from ThaiHostTalk.com.

The scaling experience of ThaiLE.com

2006-05-31T21:12:00.000+07:00

My presious post regarding Web Server Performance Comparison ends with a note about ThaiLE.com. Now's the time to write about it some more.

ThaiLE.com is the largest banner exchange network in Thailand with over 2 million banner exchange requests a day, as of April'06. This means basically about 10 million SQL queries per day. It comes with real-time transaction update and a lot of other features and resides on a single Dell server (P4D 3.0G, 2G RAM, 70G SCSI 15000rpm). The server runs Gentoo Linux with NPTL and a lot of other optimizations.

It used to be LAMP (Linux, Apache2, MySQL and PHP) and now it's 3LMP (Linux, LSWS, Lighty, MySQL and PHP).

During May we saw a traffic growth of over 30% and it's time to do something about the server.

Toward the end of April, server load average was pretty high, and I started to play with lighty first becuase of its open source nature. Lighty was able to cut down on our LA about 20-30% during peak hours, while memory pressure was reduced about as much as 30-40%. But there were problem in a prior version of lighty that forced me to investigate lsws. With lsws, the lightened feeling that I'd experienced with lighty has carried on, and since its watchdog process is better that lighty, there have been just slight problems with lsws since a month ago. Now with its latest version, I'd be able to sleep soundly at night and the system is able to scale some more without adding any hardware. ;)

Oh well, lsws STD edition wouldn't give you more than 300 concurrent connections, I have to add lighty running on a second IP on the same machine to serve just banners. Swap space usage is almost nil (while it was couple hundred M during Apache2 tenure) and the system is able to serve about 3 million banner exchange transactions a day (or ~ 15 million MySQL queries) without any problem, web-server-wise.

Next thing to tinker with was MySQL and it is now fixed by migrating a couple high traffic tables to memory (heap) tables with cron jobs to update the on-disk tables with current values from memory.

End note, Apache is good, Lighty is good, LSWS is good. Choose the ones that best suits your needs. Also, I don't notice speed advantage of lsws over lighty but the experiment shows that lsws is of better stability than lighty when running with php-fastcgi (phplsapi in case of lsws).

Cudos to all people that make possible all those great software.

High Availability, and a lot... (work in progress)

2006-05-31T20:57:00.000+07:00

High Availability
As more and more mission-critical applications move on the Internet, providing highly available services becomes increasingly important. One of the advantages of a clustered system is that it has hardware and software redundancy, because the cluster system consists of a number of independent nodes, and each node runs a copy of operating system and application software. High availability can be achieved by detecting node or daemon failures and reconfiguring the system appropriately, so that the workload can be taken over by the remaining nodes in the cluster.

pizzaman: "There are so many possible scenarios for doing HA stuff, hope that I'll be able to play with more of them soon."

Edit: Aug 16, 2006:

During this 3 days holiday, I've read through a lot and found many interesting solutions including:

LVS itself (of course)
Linux-HA
pound
pen
HAProxy

Several nice articles:

How to setup HA-LB apache cluster (using LVS)
How to setup HA NFS server with DRBD
HA NFS from linux-ha, including lock test results (however, the article is quite old and those problem should be solved by now)
How to aggregate apache log files from several nodes
NFS and LVM: We will need to work with shared NFS resource in our cluster
RHEL4 NFS reference
DRBD itself, so-called network RAID-1 data replicator(?)
RedHat cluster suite + GFS

I later stumbled upon:

Kevin Minnick's comments on these solutions (although I think pound doesn't provide HA on its own). Kevin touches upon perlbal, a good perl-based RP and load balancer that I've never heard of until now. Got to have a look later.
At danga, I saw its DFS called MogileFS. Looks cool, altought it lacks POSIX compliance that I need.

The adventures of scaling, Stage 1

2006-05-09T13:27:00.000+07:00

The adventures of scaling, Stage 1

Linux performance tuning

2006-04-28T23:24:00.000+07:00

The C10K problem
Old doc but very useful
RH system stat tools

Upgrading Red Hat Linux/Fedora Core with yum

2006-04-18T19:53:00.000+07:00

Upgrading Red Hat Linux/Fedora Core with yum
It is possible to upgrade your Red Hat Linux/Fedora Core system using yum instead of the CD/DVD-based install or upgrade option. Only experienced Red Hat/Fedora Core users should attempt this, as the yum upgrade process is not officially supported and may cause problems.

mod_rewrite | mod_proxy & stuff

2006-03-26T22:12:00.000+07:00

Apache module mod_rewrite

mod_rewrite, a beginner’s guide (with examples)

more .htaccess tips and tricks

How to properly proxy mod_perl request to a different backed using mod_proxy and mod_rewrite. Also mentions about "Closing Lingering Connections with lingerd".

[PHP-DEV] Re: Moving to PHP5.1 and Apache 2.2 next year, need help

2006-02-28T14:49:00.000+07:00

[PHP-DEV]Have you considered using lighttpd with fastcgi loadbalancing and caching using mod_cml (cache meta language)?

Web Server Performance Comparison

2006-02-23T16:10:00.000+07:00

Web Server Performance Comparison
is actually a benchmark performed by litespeedtech (litespeed web server--lsws).

Prior to the past couple months, I've never looked at anything except apache as a web server, except perhaps tux. But as a few hosting servers have been pretty hard hit by the users, I needed something lighter. ThaiLE.com had also reached its capacity with apache2. Finally, all these have forced me to take a serious look at something to replace or work alongside apache.. and I've found these two. Lighttpd (lighty) and Litespeed Web Server (lsws). In short, they work.

Read more about our experience with these stuff soon.

TextDrive Weblog: Taking a full frontal slashdot lighttpdly

2006-02-23T16:08:00.000+07:00

TextDrive Weblog: Taking a full frontal slashdot lighttpdly

Quick and Dirty Data Extraction in AWK | Linux Journal

2005-11-15T17:45:00.000+07:00

Quick and Dirty Data Extraction in AWK | Linux Journal

Need to pull some data from text--maybe e-mail messages--and sort it, graph it or otherwise manipulate it? Here's an AWK script to use as a starting point.

GRUB from the ground up

2005-11-14T16:39:00.000+07:00

http://www.troubleshooters.com/linux/grub/grub.htm

Grub is a world-class boot loader with insufficient documentation. In many ways it blows the doors of LILO. For instance, it's MUCH easier to use Knoppix to rebuild a grub boot loader than to rebuild a LILO boot loader. However, until you're comfortable with grub, it might seem just the opposite. All too often grub dumps you at a grub> prompt with no hint of what you should do. You might have heard that a successful reboot is just three commands away, but which commands? The state of grub's documentation is such that you can't figure it out unless you already know grub.

That catch 22 is the very purpose of this document. This document will to give you enough grub expertise that you can create a grub boot floppy on a working machine with grub installed (not necessarily as the bootloader, just installed), and use that floppy to bust back into a Linux machine with a blown bootloader, and then use that floppy to actually install grub as the bootloader.

This document does not discuss using grub to boot or dual boot Windows, mach, BSD, or other non-Linux operating systems. I might write on that subject later. But in the meantime, once you're familiar with the principles and practices of grub, given some study of existing documentation you'll probably be able to use grub to boot non-Linux operating systems.

OceanStore

2005-07-23T14:25:00.000+07:00

OceanStore

OceanStore is a global persistent data store designed to scale to billions of users. It provides a consistent, highly-available, and durable storage utility atop an infrastructure comprised of untrusted servers.

Any computer can join the infrastructure, contributing storage or providing local user access in exchange for economic compensation. Users need only subscribe to a single OceanStore service provider, although they may consume storage and bandwidth from many different providers. The providers automatically buy and sell capacity and coverage among themselves, transparently to the users. The utility model thus combines the resources from federated systems to provide a quality of service higher than that achievable by any single company.

OceanStore caches data promiscuously; any server may create a local replica of any data object. These local replicas provide faster access and robustness to network partitions. They also reduce network congestion by localizing access traffic.

We must assume that any server in the infrastructure may crash, leak information, or become compromised. Promiscuous caching therefore requires redundancy and cryptographic techniques to protect the data from the servers upon which it resides.

OceanStore employs a Byzantine-fault tolerant commit protocol to provide strong consistency across replicas. The OceanStore API also allows applications to weaken their consistency restrictions in exchange for higher performance and availability.

Firewall script on Virtuozzo VPS

2005-07-11T18:04:00.000+07:00

http://vpsinfo.nixhost.net/firewall.htm lists some good IPTables firewall script to be used on Virtuozzo VPS.

cPanel + Trustix for Hosting

2005-07-04T09:35:00.000+07:00

This is a log of Trustix+cPanel additional configuration. Trustix+cPanel has a few broken configurations needed to be fixed before production deployment.

Logrotate:

Add extra /etc/logrotate.d/httpd

/usr/local/apache/logs/error_log /usr/local/apache/logs/access_log /usr/local/apache/logs/suexec_log {
postrotate
/usr/bin/killall -HUP httpd
endscript
}

Add these few lines to /etc/logrotate.d/syslog and remove duplicated values from old file

/var/log/messages /var/log/secure /var/log/maillog /var/log/boot.log {
sharedscripts
postrotate
/bin/kill -HUP `cat /var/run/syslogd.pid 2> /dev/null` 2> /dev/null || true
endscript
}

- comment out named stuff from /etc/syslog.conf and change local2.* to /var/log/message
- add this to /etc/cron.daily/logrotate

export TMPDIR=/var/log/tmp

- additional stuff

cd /var/log
rm -rf named
mkdir tmp # our /tmp is mounted suexec, hence we need this
chmod 755 tmp
chown syslog:syslog tmp message message.* maillog maillog.* secure secure.*
export TMPDIR=/var/log/tmp

swup --install glibc-locales (so a couple pkg that needs locale data will work correctly--such as squirrelmail or autoresponder in cPanel)
swup --install uw-imap-devel libimap (need this to make php-imap compile)
To update clamav -- installed with exisscan --> GOT to config exim first, look from current servers

cd /root/src
wget http://umn.dl.sourceforge.net/sourceforge/clamav/clamav-0.82.tar.gz
tar -xvzf clamav-0.82.tar.gz
cd clamav-0.82
./configure --prefix=/usr --sysconfdir=/etc; make; make install
cp /etc/clamav.conf /etc/clamd.conf
service exim restart

add RBL to /etc/exim.conf (Edit: this is now outdated. I'll write about exim+SA+clam later.)

#!!# ACL that is used after the RCPT command
check_recipient:
# Exim 3 had no checking on -bs messages, so for compatibility
# we accept if the source is local SMTP (i.e. not over TCP/IP).
# We do this by testing for an empty sending host field.

accept hosts = +relay_hosts
endpass

accept authenticated = *

drop dnslists = sbl.spamhaus.org: relays.ordb.org: list.dsbl.org: bl.spamcop.net: xbl.spamhaus.org

message = your mail server $sender_host_address is in a black list at $dnslist_domain ($dnslist_text)

Then to prevent cPanel from overwriting this modified config; chattr +i /etc/exim.conf

To further prevent spam, this is real cool .. http://forums.cpanel.net/showthread.php?t=31710 it contains the instruction on how to setup exim to prevent spam using the list of domains that are found in the body of spam messages.

cPanel's mod_gzip installation is really dangerous. You better change these lines in httpd.conf:

# change max file size from unlimited to 500k to prevent overcommitted /tmp partition
mod_gzip_maximum_file_size 500000
# and add these lines to ignore graphic & compressed files
mod_gzip_item_exclude mime ^image/
mod_gzip_item_exclude file \.bz2$
mod_gzip_item_exclude file \.tbz2$
mod_gzip_item_exclude file \.gz$

Update 2005/08/03:

Install exim+clamav
Also config like ours

Update 2006/02/03:

Since cPanel does not support Trustix any more, and also Trustix has stopped being a good guy, I decided it's not worth it to pursue another good distro and focus only on RHES, CentOS, and Gentoo.

The day the newspaper dies

2005-06-19T15:12:00.000+07:00

No, that's too much of the headlines. That's not impossible. Com'n, no way.

And now the news in detail.

One-fifth of Web users prefer online news - Nielsen

SAN FRANCISCO (Reuters) - Nearly one-fifth of Web users who read newspapers now prefer online to offline editions, according to a new study from Internet audience measurement company Nielsen//NetRatings.

The first-time study from Nielsen//NetRatings found that 21 percent of those Web users now primarily use online versions of newspapers, while 72 percent still read print editions.

...

U.S. newspaper circulation has been falling as audiences increasingly turn to the Internet for news -- both on newspaper-run sites and through companies such as Yahoo Inc. (Nasdaq:YHOO - news) and Google Inc., which display news gathered from various sources.

That day is coming slowly but surely. But no the printed papers will never die, but the mixture will change, for good.

Interestingly Gentoo

2005-06-19T09:56:00.000+07:00

Updated June 19, 2005: Gentoo encrypted FS

Note on baselayout change: Today, I ran emerge -a baselayout to find out that there are several changes to /etc. If etc-update is ok, then there's nothing actually to worry about since new scripts will still honour my old config files. The new way of setting up host/domain name and network has changed a bit. Note here just for the record.

#/etc/conf.d/hostname
HOSTNAME="myhost"
#--- and remove /etc/hostname

#/etc/conf.d/domainname
OVERRIDE=1
DNSDOMAIN="mydomain.com"
#--- and remove /etc/domainname

#/etc/conf.d/net
config_eth0=( "203.146.251.2 netmask 255.255.255.128 broadcast 203.146.251.255" )
routes_eth0=( "default via 203.146.251.126" )

Now go read /etc/conf.d/domainname and /etc/conf.d/net.example too.

Updated April, 2005: Apache Package Refresh Why do they have to do that! :(

Java 1.5.0 Beta 1 is out - Installation w/o Ebuild

How to boot Gentoo LiveCD with a non-booting CD-ROM or BIOS!

How to do a gentoo install on a software RAID

HOWTO: Bond two NICs together and connect to a Cisco switch

How to integrate Samba into Active Directory

Installing portage on other distros, easier than ever

HowTo - Install Gentoo LiveCD Wirelessly!

Quick Gentoo Linux Installation and Configuration

Gentoo Linux Documentation -- qmail/vpopmail Virtual Mail Hosting System Guide

Gentoo Forums :: HOWTO: qmail vpopmail courier-imap qmail-scanner etc (NEW)

Excellent Guide to Running qmail under Gentoo Linux

Gentoo Forums :: HOWTO: Downgrade from apache2 to apache 1.3.x

Gentoo Forums :: Eric's Web Server How-To (For new installs & n00b's)

Gentoo Forums :: Virtual hosting made easy

Gentoo Forums :: Integrate Tomcat With Apache Using mod_jk

Gentoo automated installation/maintenance guide
This document describes a system for building pre-configured client PC's on a variety of hardware and a scheme for centrally maintaining the packages and files deployed based upon the Gentoo binary packaging system.

more?

God of Links:
Gentoo Forums :: Index
Gentoo Linux -- The Fresh Ebuilds

Gentoo + qmail-scanner + spamassassin

2005-06-08T00:11:00.000+07:00

Installing qmail-scanner with spamassassin and other helpers (such as razor2, dcc) is not that difficult, but several docs on Gentoo site, such as this good & popular & bloated topic are outdated. One thing that caused me quite a bit of pain is that qmail-scanner not detecting spamassassin. This topic helps solve the issue. Qmail-scanner ebuild uses ST patch, which is located here. I found some nice articles comparing various network tests using in spamassassin in spamassassin book. Last comment is to install mail-filter/spamassassin-ruledujour from the ebuild too.

It's time to do mod_security

2005-06-03T16:28:00.000+07:00

One of our servers got hacked 3 times in 5 days, due to unpatched phpBB and another popular OSS. Although we're successful in stopping the old hack by modifying those outdated scripts, but new hack keeps coming in to some other customers' sites. I'm fed up with this and decide to go ahead with installing mod_security to at least prevent URL injection and several other things. For cPanel servers, just read this thread with nice (but sometimes too much) examples of modsec.user.conf.

I then added these few lines to cPanel's default config:

# added by KM
SecFilterSelective THE_REQUEST "lynx "
SecFilterSelective THE_REQUEST "scp "
SecFilterSelective THE_REQUEST "ftp "
SecFilterSelective THE_REQUEST "cvs "
SecFilterSelective THE_REQUEST "curl "
SecFilterSelective THE_REQUEST "telnet "
SecFilterSelective THE_REQUEST "ssh "
SecFilterSelective THE_REQUEST "echo "

eicar - Anti-Virus test file

2005-05-25T17:09:00.000+07:00

eicar - Anti-Virus test file I wanted to look for this site for quite a while, but just today that there's a real need to use it. It contains quite a number of virus signature.

Blurp

2005-05-20T22:04:00.000+07:00

Today's the boring day. Believe me, it's full of rain and rain. Watching 2 movies in a row, in my house. So I guess it's a good time to setup a new blog site here, and moved almost all old articles from my old blog.

Unix Command line Email tool

2005-05-20T09:24:00.000+07:00

Email. Unix Mail The Easy Way. Comes with a lot of options and ability to specify smtp server ip and port. Means that you don't have to have MTA running on the machine you want to send email from. It will connect to another host that has MTA and open for your host to relay. Excellent tool. Found this tool long ago but just think of writing some note about it here.

Movie Quotes

2005-05-18T09:24:00.000+07:00

Memorable Quotes from Spider-Man (2002) Remember this? "With great power comes great responsibility." Yeah, that's him. Peter Parker - "Whatever life holds in store for me, I will never forget these words: 'With great power comes great responsibility.' This is my gift, my curse. Who am I? I'm Spider-man." I also like this one, "Let me buy you a cheese-burger - sky's the limit, up to seven dollars and eighty-four cents." Go Peter! :-)

Open Source IM

2005-05-14T09:29:00.000+07:00

Jabber : The Linux of IM. May be this is what I'd like to do as a hobby? Jabberd 2.0 project page. And JabberStudio : the development hub for the Jabber community. A great piece of software, Qnext a next-gen IM and private P2P app. Jabber Inc offers commercial enterprise IM suite.

Media Monitoring

2005-05-13T09:32:00.000+07:00

One of the tasks Smile Interactive is working on is related to Media Monitoring. So off we go... Open Directory - News: Services: Media Monitoring : Take a look at thie media monitoring stuff. Especially AudioAudit site.

Linux LVM

2005-01-25T09:36:00.000+07:00

Quite a few LVM articles

Work on VPN

2005-01-01T09:37:00.000+07:00

Requirements:

Linux GW behind NAT FW (LAN --- VPN GW --- ISP's NAT FW --- Internet --- RoadWarriors)
RoadWarriors with Windows XP clients
X 509 certificate
Using Trustix Enterprise FW product

Readings:

FreeS/WAN FAQ (Trustix is based on FreeS/WAN)
X 509 FreeS/WAN Install & Config doc (with doc on Virtual IP and wildcart subnets)
Mentioning Windows XP Client & cert setup process
Automated CMAK to streaming VPN client cert

Current problem:

Trustix alone is not possible, having a problem with NAT packet
Asking for suppot from Trustix and waiting...
Problem detail is here (in Trustix forum)

Update (2004/11/28):

I think I found an idea from reading the docs above
From this doc
and from here
This is a very cool NAT + VPN setting
Advanced config: RoadWarrior with Virtual IP

Update (2005/01/01):

The plan to using Trustix package is now scrapped. Trustix comes with an old version of FreeS/WAN with X509, BUT without NAT-T patch. I couldn't patch the package myself without proper source made available by Trustix.

End result:

Switched to using OpenVPN and it's done in a few days. I'll post more about this stuff later on.

Linux Boot process

2004-12-12T09:38:00.000+07:00

Bootchart
Boot process visualization

Programming Puzzle

2004-12-05T09:38:00.000+07:00

No, I didn't answer all those myself :-)

1. Write a "Hello World" program in 'C' without using a semicolon.

void main()
{
if (printf("Hello World!\n") {}
}

2. Write a C++ program without using any loop (if, for, while etc) to print numbers from 1 to 100 and 100 to 1;

void main()
{
printf("1\n2\n3\n... and so on...");
}

3. C/C++ : Exchange two numbers without using a temporary variable.

x^=y; y^=x; x^=y; #XOR!

4. C/C++ : Find if the given number is a power of 2.

if (!( x & (x-1)) printf("x is a power of 2\n");

5. C/C++ : Multiply x by 7 without using multiplication (*) operator.

x = (x6. C/C++ : Write a function in different ways that will return f(7) = 4 and f(4) = 7

int function(int x) {
switch (x)
{
case 7: return 4;
case 4: return 7;
}
}

6. C/C++ : Write a function in different ways that will return f(7) = 4 and f(4) = 7
7. Remove duplicates in array
8. Finding if there is any loop inside linked list.
9. Remove duplicates in an no key access database without using an array
10. Convert (integer) number in binary without loops.

I assume you mean to print the binary form of an int without using loops. So I didn't use a loop, I used recursion.

;)

void printbits(int x)
{
int n=x%2;
if(x>=2) printbits(x/2);
printf("%d", n);
}

11. Write a program whose printed output is an exact copy of the source. Needless to say, merely echoing the actual source file is not allowed.
12. From a 'pool' of numbers (four '1's, four '2's .... four '6's), each player selects a number and adds it to the total. Once a number is used, it must be removed from the pool. The winner is the person whose number makes the total equal 31 exactly.
13. Swap two numbers without using a third variable.

Same problem as #3 above.

14. Given an array (group) of numbers write all the possible sub groups of this group.

Google & Gmail!

2004-10-21T22:42:00.000+07:00

Slashdot | Gmail in the News
Slashdot | Gmail Addresses For Sale
Me think... what else can go wrong? :)
Slashdot | How does Google do it?

Ads and Politics

2004-10-20T09:43:00.000+07:00

Apple Ads
Windows 95?

Interesting Unix commands

2004-10-13T09:45:00.000+07:00

To kill processes owned by _something_

# ps wuax|grep _something_|awk '{print $2}'|xargs kill -9

Regarding Linux Backup

2004-10-08T09:47:00.000+07:00

Distributed Internet Backup System
Find the time to read it.

rsyncBackup
rsyncbackup is a perlscript that reads configuration files for sources and destinations, and feeds the rsync tool with the appropriate parameters. rsyncbackup is written on Mac OS X, but will probably work on every system that have both perl and rsync installed.

I'm building a 1.5TB fileserver for work...

Slashdot articles about backup

Slashdot | Terabyte Storage Solutions?

Slashdot | Home-brewing a 1.2TB IDE to Firewire Monster

Slashdot | Bulk Data Storage For The Common Man?

Slashdot | Reliable, Affordable Online Backup Providers?

Slashdot | Server Redundancy for a Small Business?

Template for Web Hosting business

2004-10-07T09:52:00.000+07:00

Template for Web Hosting business

Nice:
http://www.templatemonster.com/website-templates/5439.html
http://www.templatemonster.com/website-templates/2242.html
http://www.templatemonster.com/website-templates/5579.html

Good for corporate site:
http://www.templatemonster.com/flash-templates/6502.html
http://www.templatemonster.com/website-templates/6509.html

LOTR Joke

2004-09-27T09:53:00.000+07:00

Of course, I'm a fan of the LOTR and here's some dose of caffeine for today. :)

LOTR Joke

cPanel Forums

2004-08-23T09:59:00.000+07:00

Exiscan+Clam+Exim Autoinstaller
Much better than Mailscanner + Clam

Mailscanner + Clam
This is the original Mailscanner/Clamav

OE-QuoteFix

2004-08-07T10:00:00.000+07:00

Update: Beep Beep, switch to Thunderbird and you'll never go back to OE.

OE-QuoteFix At last, I've found this piece of wonderful software. Can't live without OE and hate OE to its core when it comes to quoting. This fixes it.

Regarding LDAP

2004-08-04T10:02:00.000+07:00

OpenLDAP - Admin guide
Cover everything. For basic, start here.

YoLinux LDAP Tutorial: Deploying OpenLDAP - Directory Installation and configuration (V1.2 / 2.x)
Found this too late. Very vaulable.

YoLinux LDAP Tutorial: OpenLDAP Directory Objects and Attributes
Show How to extend LDAP schema.

Ldap How-to

LDAP receipe
A Recipe for Configuring and Operating LDAP Directories

LDAP Implementation HOWTO

Addressbook section:

Creating a central outlook addressbook with OpenLDAP howto-Gentoo way

Using PHP with LDAP
This one is good for start.

PHPBuilder.com - Create an LDAP Address Book

freshmeat.net: Project details for ldap-abook

Qmail:

Qmail toaster
A source version of Qmail toaster. Great one.

Qmail toaster RPM
This is the RPM version.

Courier imap

vpopmail+LDAP:

vpopmail Ldap
This is the one I used as a starting point for vpopmail+LDAP.

LDAP vpopmail
Message detail LDAP+vpopmail. Quite old but useful.

phpQLAdmin
Great PHP tool to work with qmail-LDAP.

The Metasploit Project

2004-08-03T10:02:00.000+07:00

The Metasploit Project "In a world where data is the coin of the realm, and transmissions are guarded by no better sentinels than man-made codes and corruptible devices, there is no such thing as a secret." - This Alien Shore

DNS based Website Failover Solutions

2004-07-31T10:03:00.000+07:00

Slashdot | DNS based Website Failover Solutions?

DNS & Spam database lookup

2004-06-26T22:38:00.000+07:00

Spam Database Lookup
Check multiple RBL here
DNS report

Regarding Exchange/Linux/LDAP

2004-06-24T22:41:00.000+07:00

SUSE Openexchange Under GPL
Real-life review of why MS Exchange sucks.

Exchange Functionality for Linux

Migrating from Exchange to OSER

Export contacts from Exchange server to LDAP

eMailman(sm) -- Conversion

Connecting POP And IMAP Clients To MS Exchange Server

Plugins:

ZideStore Server / ZideLook Outlook Plugin

Online game infrastructures

2004-06-11T22:43:00.000+07:00

Online game infrastructures: Develop a high-level business description and identify patterns
READ IT! :-)

Online Banking

2004-05-06T09:21:00.000+07:00

A few online banking site. Wells Fargo - Online Applications US Bank account. Also check out WF checking info and its Online banking

DRobbins - Reasons for Forking A Linux Distribution

2004-05-04T22:48:00.000+07:00

Reasons for Forking A Linux Distribution
Um... so is D Robbins actually a knight in shining armour? More to research.

Virtuozzo pricing

2004-05-02T22:49:00.000+07:00

This is old ---
Virtuozzo price

Base System Price
1CPU 10-VE $1,000.00
30-VE pack $1,500.00
100-VE pack $2,000.00
250-VE pack $3,000.00

2CPU 30-VE pack $2,250.00
100-VE pack $3,000.00
250-VE pack $4,000.00
500-VE pack $5,000.00

Lease 1-CPU Lease 2-CPU
Base System 10-VE $100 N/A
30-VE pack $150 $225
100-VE pack $200 $300
250-VE pack $300 $400
500-VE pack N/A $500

From FC1 to FC2 in cPanel

2004-04-17T09:48:00.000+07:00

http://forums.cpanel.net/showthread.php?t=27923
http://linux.duke.edu/%7Eskvidal/misc/fc1-fc2-yum-hints.txt
(the latter is from the creator of Yum, but someone said it breaks the instruction on the first topic)

Update: If you get a problem building apache in FC2 with "libxpm" issue, then install this libxpm or simply go directly to get this file before doing the compilation.

Found a new interesting win cp

2004-03-13T22:53:00.000+07:00

Inspedium Corp. - Software, Hosting Control Panel, Mail Server, Windows 2003, Windows 2000 Site very slow, however. Check out later on.
Ooh, another one. This is free, but still not well integrated. ZPanel - Taking your hosting to the next level.

Current issues with Windows hosting

2004-03-13T22:52:00.000+07:00

- prefer mail server to run on linux with virus/spam protection but can't find a decent one except HSP.

At this time, looks like:

x Ensim is a NO due to its old software package
x Plesk is a NO (100 domain-$40/mo) due to missing bandiwdth control
x Hsphere (psoft) is very good, but a NO at this point. ($3.5/account ~ $175 initially) Don't want to waster another machine for the cp.
/ Helm is pretty native and stay with windows pretty co-operatively, but no mail & DB quota, etc... (1 server promo, $129 at Helmtastic.com)

Update 05/2005: I think Plesk 7.5 has quite a way to go ...

Helm Single Server License and Turnkey Installation Speical

2004-03-13T22:51:00.000+07:00

I found this interesting service. Helm Single Server License and Turnkey Installation Speical $275

*PHP4 with fast CGI, Curl, Session Variables, Zend Optimizer, more...
*MySQL correctly set up to work on Windows....
*phpMyAdmin (global shared installation)
*MySQL-Front *OBDC Connectors from MySQL
*OBDC Connectors from Microsoft to connect ASP.net applications to MySQL
*ActiveState Perl
*AWStats
*SmarterMail
*SmarterStats
*Single Server License of Helm installed and configured with a sample reseller, user...
*Antivirus Application (license provided by you.)
*MySQL Back Up Script scheduled to run daily.
*Helm DB Back Up Script scheduled to run daily.
*Zipped Back Up to back up the customer domains and other items scheduled to run daily.
*Some Sample Scripts to verify the server is working including ASP and ASP.net.

More info here

The Internet Timeline

2004-02-28T22:58:00.000+07:00

Hobbes' Internet Timeline - the definitive ARPAnet & Internet history Got to find the time to read it again. :-)

Windows CP

2004-02-26T22:55:00.000+07:00

Helm WebHosting Control Panel : The Windows Multi-Server Web Hosting Control System

Products - SmarterTools Inc.
Upgrade from Helm's bundled 50 site license to:
- 250 dom/1000 users for +$100
- unlimited for +$300
+ Add: Trend server protect for +$199
Upgrade from SmaterStat 50 site license to:
- 250 sites for +$100

SWsoft Plesk 7 Details

Ensim - Ensim Pro for Windows Frequently Asked Questions

Update 05/2005: This post started it all with my Blog.