Business

Linux comes with various GUI based email client to stay in touch with your friends and family and share information in newsgroups with other users. The following software is similar to Windows mail. In this post, I will list some of the best Linux email clients for desktop. Some of these clients work on macOS and Windows too.

Best email clients for Linux, macOS and Windows

Webmail interfaces allow users to access their mail with any standard web browser, from any computer, rather than relying on an e-mail client. However, e-mail client remains extremely popular in a large corporate environment, small business, home and power users. An email client (also mail user agent (MUA)) is a frontend computer program used to manage e-mail. Mail can be stored on the client, on the server side, or in both places. Standard formats for mailboxes include Maildir and mbox. The following are top thirteen fantastic pieces of cross-platform software from various projects to make your life easy with a wide variety of plug-ins/add-ons.
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Research shows that if your web pages take longer than 5 seconds to load, you lose 50% of your viewers and sales. As a UNIX admin often end users and web developers complain about website loading speed and timings. Usually, there is nothing wrong with my servers or server farm. Fancy java script and images / flash makes site pretty slow. These tools are useful to debug performance problems for sys admins, developers and end users. Here are six tools that can analyzes web pages and tells you why they are slow. Use the following tools to:

  • Make your site faster.
  • Debug site problem, especially client side and server side stuff.
  • Better user experience.
  • Improve the web.

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Unplanned downtime may be the result of a software bug, human error, equipment failure, power failure, and much more. Last week was a bad one. We faced three different downtime:

  • First, there was a fiber cut for one of our data center resulting into routing anomalies due BGP reroute. Traffic was rerouted but updating those BGP tables took some time to update.
  • Someone from networking team failed to follow proper maintenance procedures for network device resulted into 55 minutes downtime.
  • One of our SAN hardware failure – Many internal UNIX / Linux web applications use SAN to store data including file server, tracking apps, R&D apps, IT help desk, LAN and WAN servers failed. This one lasted for 12 hrs. It was stared around midnight. The vendor replaced entire SAN hardware. Now we have dual stacked SAN as a backup device for internal usage.

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Wow, this is a large size desktop hard disk for storing movies, tv shows, music / mp3s, and photos. You can also load multiple operating systems using vmware or other software for testing purpose. This hard disk comes with 5 year warranty and can transfer at 300MB/s. From the article:

It’s been more than 18 months since Hitachi reached the terabyte mark with the Deskstar 7K1000. In that time, all the major players in the hard drive industry have spun up terabytes of their own, and in some cases, offered multiple models targeting different markets. With so many options available and more than enough time for the milestone capacity’s initial buzz to fade, it’s no wonder that the current crop of 1TB drives is more affordable than we’ve ever seen from a flagship capacity. The terabyte, it seems, is old news.

Fig.01: Seagate's Barracuda 7200.11 1.5TB hard drive

The real question is about reliability. How reliable is the hard disk? So far my Seagate 500GB hard disk working fine. I might get one to dump all my multimedia data / files 🙂

I was a big fan of OpenDNS dns service, but recently I found few bad things about their offerings. I strongly recommend to stay away from OpenDNS service.

All your search queries belongs to OpenDNS

OpenDNS redirects all your Google search queries though their servers. They captures your search query data and they forwards to real google.com domain. Here is a quick DNS lookup:
$ host www.google.co.in 208.67.220.220
Sample output:

Using domain server:
Name: 208.67.220.220
Address: 208.67.220.220#53
Aliases:

www.google.co.in is an alias for www.google.com.
www.google.com is an alias for google.navigation.opendns.com.
google.navigation.opendns.com has address 208.67.219.230
google.navigation.opendns.com has address 208.67.219.231

They may also do same for your email and other search engine.

Update: Dave has pointed out the reason why OpenDNS forwards google through their server. You can also turn on or off this feature from OpenDNS control panel.

OpenDNS is bad for server

Don’t use them on your colocated server or vps server. They redirect web browser users or scripts accessing nonexistent domains to a page containing sponsored search results, ads, and a search form. The DNS protocol requires that a query for a nonexistent domain must return the “NXDOMAIN” error response. Here is a sample output:
$ host abcabcxyzxyz.com 208.67.220.220
Sample output:

Using domain server:
Name: 208.67.220.220
Address: 208.67.220.220#53
Aliases:

abcabcxyzxyz.com has address 208.67.219.132
Host abcabcxyzxyz.com not found: 3(NXDOMAIN)

This encourages spam as you will not able to filter out spam queries using their dns servers.

OpenDNS caching sucks

I contacted their support about my problem but never got any reply. Their server always returns two IP address for my nameserver:
$ host ns2.nixcraft.net 208.67.220.220
Sample output:

Using domain server:
Name: 208.67.220.220
Address: 208.67.220.220#53
Aliases:

ns2.nixcraft.net has address 74.86.48.98
ns2.nixcraft.net has address 74.86.48.98

I don’t have 2 IP address for ns2.nixcraft.net.

I strongly recommend running your own dns cache server along with your ISP forwarding nameservers.

Thanks to ricko for pointing out OpenDNS issue in a chat room and elsewhere on the Internet.

Update: Fri Nov 5, 2010 by Vivek: OpenDNS no longer redirects Google search queries though their servers:

$ host www.google.co.in 208.67.220.220
Using domain server:
Name: 208.67.220.220
Address: 208.67.220.220#53
Aliases:

www.google.co.in is an alias for www.google.com.
www.google.com is an alias for www.l.google.com.
www.l.google.com has address 173.194.33.104

Updated for accuracy.

Most computer manufacturer try to sell you extended warranty or a service contract. These warranty covers two years past the manufacturer’s one year warranty. Most sales employees or OEM (manufacturers) make so much commission from selling extended warranties. This is nothing but rip-offs, IMHO.

If I build a computer for myself by purchasing parts I get following warranties:
=> Intel CPU and motherboard – 3 years warranty
=> Seagate hard disk – 5 years warranty
=> Nvidia chipset display card – 3 years warranty
=> Dell / Samsung 27″ TFT Monitor – 3 years warranty
=> DVD / CD Write combo / keyboard / mouse – 90 days warrant (but works for years w/o a problem).

Most OEMs will not pass these warranties to end user. I never buy an extended warranty. I own 2 desktops, 2 laptops (Dell and Sony) and total 5 enterprise grade rack mount servers for my personal use. All are build using parts except laptops. Let me tell you simple truth:

It is cheaper to pay for repairs as and when they happen rather than buy a warranty. Extended warranties are not a good investment, period.

Today you don’t require tools to build PC. All you need is screwdriver to fix a computer. I only open my computer when I need upgrade or replacement of hard disk etc. If you use Windows, you simply need to use updated version of anti-virus / anti-spyware cleanups program.

Finally, if you need an extended warranty make sure you get answers to the following questions:

  1. Is the warranty transferable?
  2. Can repairs be performed at any repair shop located anywhere in the world?
  3. Find out what’s covered and what’s not covered.
  4. Make sure it is not reimbursement based warranty. For example, some computer repair shop require that you pay the bill and then send receipt to OEM and wait for reimbursement.
  5. Always read the fine print. For example, If you drop or broke something there is no warranty.
  6. Use the Internet to dig out information about product and services. Search mailing lists and forum for product. See the current user satisfaction level.

Please add your opinion about extended warranties in the comments.

If the cost of Windows eating us your small business budget, make a wise business decision and move to Linux. From the PC World article:

Windows Vista debuted to muffled applause, followed by lackluster sales. Up until June 30, cash-strapped businesses looking to avoid the cost of upgrading to new Vista-compatible hardware could still purchase trusty Windows XP. Now, however, Windows XP is available only as a costly “downgrade” from Windows Vista–if you buy a copy of Vista, you can install the 6-year-old XP operating system using the Vista license.

If that feels like a waste of your small business’s precious IT budget, and you’re still looking for an alternative to Windows Vista, look no further than Linux.

=> Move Your Business from Windows to Linux

Linux is extremely powerful, robust and flexible, which means it must have a significant amount of complexity. Do you think I learnt everything in a day? I don’t know who told you Linux was easy, many times other people make it harder than it has to be by thinking they need to understand everything at once.

Some Preliminary Advice

Some recommendations I would give you before you began with Linux:

  • Take it easy. Frustration makes things worse for everyone.
  • Never try anything for the first time in a production environment. Always use test environment. For example, iptables firewall or complex security configurations. Always use a test computer or virtual machine to test the various applications, configurations and settings. It will save lots of time. Recommended virtualization software – Vmware or Xen or VirtualBox
  • Another option is start your journey with with LiveCDs. See the list of all Linux, BSD, LiveCDs and LiveDVDs here.
  • Always refer to hardware compatible list (HCL) and kernel source documentation directory (/usr/src/linux/Documentation/) to check your hardware compatibility.
  • Learn to read and search command man pages and vi / vim text editor. Type vimtutor at a shell prompt. The Vimtutor is useful for people that want to learn their first Vim commands.
  • Don’t try to set or create ultra secure servers / services on your first shot. Mess with test system couple times i.e. play for a while until you understand everything. Don’t stress out for the perfect solution, it will slow you down.
  • Stay away from advanced stuff until you learn the basic stuff like, ssh, vi text editor, directory structure, log files, searching and greping files, network configuration, package management, patch management, troubleshooting techniques using host, ping, route, ifconfig and other tools.
  • Learn regex and text utilities such as sed, awk, grep and others. It will save lots of time in a long run.
  • Learn to customize your own login environment. This will give you good idea about many configuration options such as ftp, vi, Gnome, Kde, GUI tools and much more. Get a good Linux book, it will be a big help (see below for recommend books).
  • Don’t hesitate to ask your questions on the forums and mailing lists. Also help others in the forums when you can. You will be supervised to find out how explaining stuff to someone else helps you understand it better.
  • Learn to automate stuff using shell scripts.
  • When you run into a problem with a configuration, make sure you read:
    • The man pages
    • The info pages
    • Read package README.txt, INSTALL.txt and other files stored in a current directory or /usr/share/doc/package-name directory.
  • Use google / yahoo search engines to do several searches with different terms. My personal experience you may get answer in the forums / websites / mailing lists. Only rarely have my problems not already been answered in the forums.
  • Subscribe to security alert mailing lists.
  • Learn to compile packages using make, configure and other build tools.
  • Once you learnt terminology and basic things, start configuring basic services such as Apache. They idea is simple start by getting something up and visible. Take a time to explore stuff and get comfortable with each service / servers. Always configure one service at a time and get familiar with them one at a time.
  • Don’t compare Windows utilities / software with equivalent Linux software. Windows is not Linux or vise versa.
  • Don’t try to replace Windows desktop with Linux desktop. Windows desktop has better applications stack. Similarly, Windows can’t replace Linux. You need to consider various factors before migrating from Windows systems.
  • Gather experience.
  • Finally, always ignore flame wars such as ‘vim vs emacs editor’ or ‘BSD vs Linux’.

Good Luck!

References / Recommend Readings:

Asus dominates the market for super small, super cheap Linux / XP based mini-notebook pc. It is believed that they may have sold over 5 million Eee PCs. Now you can grab this PC for free. Royal Bank of Canada (RBC) is running spring 2008 promotion and giving out a free Asus EEE PC for every new account opened with them. Similarly you can signup to T-Mobile’s ‘Web n Walk’ max mobile boradband package for £35 per month ona 24 month contract and get a free USB modem and a free Asus EEE PC ultra mobile PC.

It turns out that people just wanted a regular laptop, but much smaller and cheaper. When Asus came out with its mostly solid state, plain vanilla PC running Linux (and now XP), the masses flocked. And now, Acer, Dell, HP and possibly Sony, as well as a smattering of smaller companies, are rushing their own cheap-and-tiny offerings.

=> Here Comes the Asus ‘Freee PC’? (via Slashdot)

An interesting interview with Canonical chief executive Mark Shuttleworth. He talks about choosing Ubuntu name and in a future undominated by Windows, how Ubuntu hopes to be the provider of a service ecosystem for free software. From the page:

Going to space and seeing the Earth from a distance makes it very clear just how interdependent we are. So I wanted to do something that was really global; free software is a phenomenon that is truly global.

=> Linux is a platform for people, not just specialists