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With perfect password manager, I thought I had the complete set of tools in my Mac for getting things done. But today I realized, I’d overlooked ethereal. I use it sometimes and it’s a gem without which it would be very difficult to solve some network problems. Ethereal is a free and open source packet sniffer application, used for network troubleshooting, analysis, software and protocol development, and education. It has all of the standard features of a protocol analyzer.

I was happy to see Ethereal for Mac OS X listed at the top of the download page. But, was confused with the choice I had to make between Fink Project and DarwinPorts. I was not sure what they meant or which one was better. So, after Googling a while and reading the FAQs, I found that the number one goal of both projects were to port open source Linux/Unix softwares to Mac OS X. They just differ in the packaging approach they’ve taken. DarwinPorts was written from scratch to try a different approach to a packaging system, where as Fink Project utilizes robust package management tools dpkg and apt-get from Debian Linux Project . So, I decided to try ethereal with Fink Project and this is how I did it.

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After switching to Mac, my Samsung notebook with Windows Xp has been free, so I decided to test dual booting Windows Vista and Ubuntu Linux in this laptop. The downloading, burning cd/dvd and installation was easy and straight forward. Only special thing I had to do was to modify the menu.lst file in Ubuntu. This is how I did it:
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Google Checkout is live. It’s a new service from Google that makes online shopping more convenient for shoppers and merchants. Shoppers can shop faster and merchants can integrate Google Checkout into their sites as an alternative payment processing method. Here is the quick video tour.

Royalty Free Stock Photography - Download 400+ quality royalty free stock photos for free. Note that these images range from 400kb to around 1.5mb, and are 1200 x 900 to 1600 x 1200. Very useful for web sites and blogs. You can post the photos without worrying about copyrights.

IP Subnetting made easy - a very good guide that explains IP Subnetting using simple graphical approach.

Learn Linux Command Lines and Shell Scripting - It’s a perfect guide for getting deeper into Linux command lines after my Getting Started with Linux Commands. This is what the author has to say about Command Lines:

I once heard an author remark that when you are a child you use a computer by looking at the pictures. When you grow up, you learn to read and write. Welcome to Computer Literacy 101. Now let’s get to work.

After installing a linux server and playing with the basic command lines, the first thing we should be able to do is configure our network, without which of course there is no Internet. Most of the latest linux distributions ship with easy to use GUI for configuration and testing of the network. But here we’ll be using all command lines. Remember, these commands directly talk to the responsible programs without any intermediary (GUI), so obviously it’s fast, more powerful and have many options that are not available in GUI.

This guide will help you to configure your network and troubleshoot simple network problems using command lines.

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Netcraft’s June 2006 Web Server Survey finds that Internet’s growth was strongest last month due to the explosion of blogs and free web sites. Also, IIS is continually gaining web server market share from Apache.

Ubuntu , SUSE , RedHat , Xandros and Linspire are doing a great job with Linux Desktop. But they’ve a long way to go, with more than 90% of Windows and around 5% of Apple only a small bite is left for them. However, the power of Linux is already proven in the server arena, currently it is powering many mission critical servers all around the world. It’s free, it’s reliable, it’s rock-solid and most importantly it’s open source. When I just started to work as an IT Engineer, I was a Windows guy. The word Unix/Linux used to scare me. Fortunately I was given a chance to learn and manage Linux Server in production environment. I was thrown into real life usage of Linux servers with live services like email, ftp, web and databases. From my experience I can say that it’s not as scary as it seems in the beginning. With some minor efforts it can be learned by any Windows users and admins.

I’ve written this guide to help beginners who’re interested in getting started with Linux. This should give you an overview of Linux and it’s basic commands.

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I’m in Guangzhou, China today to reinstall one of our Linux SMTP Server. I’ve installed CentOS 3.x with software mirroring. It’s pretty straight forward to make the Linux Software Raid partition during the installation but by default the system will boot only with the first hard disk (id0). This means if the first hard disk (id0) fails then the second hard disk (id1) will not be able to boot alone.

In order to make sure that the server can boot from each of the mirrored hard disk in case the other one fails, you need to run grub and install onto all other drives that are part of raid that the /boot partitions are on.

• #grub
  grub>
  grub>find /grub/stage1
  This will give list out where all the grub setup files are located:
  (hd0,0)
  (hd1,0)

sda=hd0 sdb=hd1 for scsi and hda=hd0 and hdb=hd1 for ide

After knowing that hd0 already has grub in mbr, we run:

• Grub>device (hd0) /dev/sdb (/dev/hdb for ide)
  Grub>root (hd0,0) and then:
  Grub>setup (hd0)

With above we’ve succeeded putting bootable mbr on the second drive and now both hard disks should be able to boot individually.

Samba 4 Technology Preview 2 is released today. Technology Preview 1 was released on January. Samba is an open source software that allows Unix/Linux system to serve as a file and print server in Windows network. The main feature in Samba 4 is the support for Active Directory logon protocols used in Windows 2000 and above.

The release notes emphasizes that this is a Technology preview to allow users, managers and developers to see how they’ve progressed and to invite feedback and support. They warn that this should not be run on production servers and is not secure.

Samba 4 Technology Preview includes basic Access Control List (ACL) protection on the main user database, but due to time constraints, none on the registry at this stage. We also do not currently have ACLs on the SWAT web-based management tool. This means that Samba 4 Technology Preview is not secure.

A serious flaw has been found in Sendmail that could allow an attacker to take control of the SMTP server running vulnerable version of the software. A remote attacker could send malicious data at certain time intervals, which can corrupt arbitrary stack memory and gain control of the Server.

This security hole affects all Linux and Unix versions of Sendmail 8 up to version 8.13.5. Microsoft Windows versions of Sendmail are not affected. Sendmail has released a new verion 8.13.6 to fix this problem and also patches for earlier versions are available at their FTP site.

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After reading Time Management for System Administrators by Thomas A. Limoncelli I wanted to try wiki system (one of the productivity tools he highly recommends) within our office because keeping the internal information up-to-date is becoming pretty difficult. Currently not everyone within the organization is able to update the information which I think is creating a big overhead. I wanted to change this with wiki system, so that the information will always be up-to-date and easy to manage.

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