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Archive for the ‘Internet’ Category

Testing Exchange Server connectivity

If you are fairly new to administering Exchange Servers, you’ll often wonder if you have configured all the connectivity options correctly. One way of checking this is to test things from both inside and outside your organisation, but sometimes you don’t have the necessary hard/software to do these tests. Enter a great solution provided by Microsoft: the Exchange Remote Connectivity Analyzer

Test Exchange  Exchange Remote Connectivity tester

This tool will let you test things such as ActiveSync, Outlook Anywhere and so forth. All you need to do is use a valid user account, and point the tester to your server(s), and wait while it attempts to connect. If it isn’t successful, it shows a log of all the steps it took, along with the point where it failed. This makes it an excellent tool for troubleshooting.

Credit for this goes to a post on the EduGeek.net forums, where I discovered this little gem. I don’t know if this works with Exchange 2003, but it definitely works with Exchange 2007 and 2010.

Internet Explorer 9 Platform Preview 2

I downloaded this in the week, as I was curious to see what the fuss was all about. Being a Platform Preview, the application is a minimal GUI over the Trident engine that powers IE. The install file was about 16MB, and it didn’t require a restart. You can download a copy here: http://ie.microsoft.com/testdrive/

The browser window is as spartan as Notepad, which in a bizarre way is actually quite cool. When you start it, it takes you to the Microsoft Demo site, where you can play around with the demos that show off some of the new features in the engine, its speed and improved web standards. Most of these are pretty boring after a while, so I opened up some real websites. I tested my school’s website (built in Joomla) and some other fairly heavy websites.

I was pleased that IE9 PP2 feels faster already than IE8, though of course this is just the raw Trident engine. My school’s website, which relies on a lot of PHP and JavaScript due to being built in Joomla, opens a lot faster than IE8. A lot of things don’t quite work in the admin backend, but I’m sure this will improve as IE9 continues to grow. Other websites showed a similar boost in speed.

I’ve often been asked why we don’t install Firefox or Chrome in the school network, and I reply that until the day you can manage it out of the box like you can with IE through Group Policy it won’t be installed. Most people never knew that, especially the students who think to show off their “l33t skillz”

I don’t know when IE9 will be released, nor if it will help Microsoft regain some points in the browser wars, but increased speed and standards support is a very big welcome. It’s unlikely to get users of other browsers to switch back, but it may stop new users from switching in the first place.

SEACOM bandwidth first hand

March 17, 2010 1 comment

Last year, the SEACOM undersea fiber optic cable landed in South Africa. This cable was many times faster than the existing SAT3 cable that most of South Africa relies on to get internet access. Along with everything else, it was expected that SEACOM would bring competition and innovative packages to market as ISP’s got connected to the cable.

Two weeks ago this became a reality for my school. Our ISP only caters for schools, and they had managed to obtain a slice of bandwidth for new packages they would be offering schools. We were offered an uncapped 2Mbit ADSL line for less than what we were paying for our uncapped 1Mbit line. Contention ratio would be fixed at 2:1, which was guaranteed unlike our previous solution with Internet Solutions.

A new router was installed on site, our firewall quickly reconfigured and we were away. A few DNS records had to be changed on their side, but once that was done everything was back to normal.

Speed is fantastic on the line. One could say that of any 2Mbit line I guess, but with contention ratios fixed, we are getting steady solid bandwidth. YouTube videos can often now be viewed without a lot of buffering for example. Downloads go so much quicker than ever before.

General browsing speed has also increased nicely, though sometimes it isn’t as noticeable.

It has reached the point that using this crummy 384k ADSL line at home is almost physically painful at times. As ADSL competition continues in South Africa, I can hope that the 384k lines will eventually get upgraded for free. I can’t live with this slow speed anymore after having SEACOM based goodness for 2 weeks now at work.

Although SEACOM hasn’t yet totally opened the market up, it is having many good effects already. Once the rest of the fiber cables land in SA, we may just start living the internet good life.

Telkom Mega 105WR: Follow up after almost a year

December 16, 2009 1 comment

I previously wrote about the Telkom Mega 105WR router here, and after almost a year’s worth of use, I thought I would do a follow up.

Most of my original comments still stand on the device, it is quite powerful and feature rich for a telco supplied device. However, one thing that has not improved is the routine freezing of the device. Almost like clockwork, the router needs to be restarted every 7-8 days, as I can’t access the web console, and wireless struggles to remain connected.

Doing some research on the router revealed that it appeared to have a high return rate, for this reason and diverse others. I looked on the manufacturer’s website for an updated firmware, to no avail. I even tried emailing their support address, to which I have still not gotten a reply to this day.

A few weeks ago, I decided to take the router back into the shop to try and get a replacement model before the guarantee ran out. I duly packed up everything and went to the Telkom shop. I was duly informed that they could not exchange the router directly, I first had to call the national ADSL support line, go through the troubleshooting tips, and then get a reference number. Come back with that they said, and we’ll do a swap. Then came the interesting news: “Telkom no longer supply this router, so you will be getting another model”

I am guessing that the problem rate with this router was high enough to cause Telkom to move to another model. I looked in the shop, and it appeared that the most likely replacement model would be another Telkom branded router, called the Duoplus 300WR. After looking up the specs of this thing on the internet, I was left less than pleased. The wireless antenna is only 3dbi, half the strength of the current model. It would mean me having to buy a new aerial, which I don’t want to do. I could be wrong however, as there were also Netgear routers in the shop, which may also be an option. I’m not fully sure.

To cut a long story short, I am still running the old Mega 105WR at home, and I’m not yet sure what I plan to do about it. I am tempted to buy a proper name brand router, but at this point I’m trying to find one that has all the features I need and is not too expensive.

My advice is that if you have one of these devices, and it routinely freezes up like mine, get the reference number, swap the model out and hopefully the newer router will perform better. I can’t recommend this router anymore, it just doesn’t perform as expected. Rather buy a name brand router, it will serve you better in the long run.

Microsoft Web Platform Installer

October 11, 2009 Leave a comment

For years, the LAMP stack has been a success story of the open source world. Based on the components of Linux, Apache web server, MySQL and PHP/Perl/Python, it has enabled many fantastic applications to be built: WordPress, Joomla, Drupal, Moodle and more. The ease of use for developers and admins has lead to this stack being almost the de facto standard for hosting these applications.

Generally these packages also worked under Microsoft’s web server, IIS, but usually with some difficulty in setting up and maintaining the site. Most of the projects help forums are for those who run it on the LAMP stack. Downloads are usually zipped, and need to be set up manually. Linux distros such as Debian may have the packages in their repositories, but they may be a little out of date.

Microsoft finally decided to help people who run Windows Servers to be able to easily join in on the party. The result was the Web Platform Installer, more information can be found here

While the focus of the tool seems to be to promote ASP.Net based applications, PHP based applications are also available and supported. Indeed, supporting these PHP applications has made installing products like Moodle and Gallery a lot simpler, as the package has scripts that set up the correct rights on folders, connection to the database and more.

The Installer sets up various aspects of IIS for you, installs a Microsoft SQL Express Database, PHP and other tools you will need for the applications.

At the moment, the number of applications is still quite small, but it is growing. Applications I wish to see in the future include PHPBB3, MediaWiki, and most importantly, Joomla. Microsoft does not package the applications themselves, but rather provides the guidelines and tools to create the packages. Hopefully members of the above mentioned communities will band together to package the apps to eventually have them appear in the Installer.

The Installer makes life easy in many ways, but it is not the be all end all. Admins still need to test the security of their websites, directory permissions and so to ensure the most secure website possible.

Overall, I really like this tool and hope that in time it will continue to grow and offer more and more killer applications. Microsoft have done sterling work to get PHP to run better and faster under Windows, and this is hopefully a sign of even more things to come.

Using multiple web browsers

September 10, 2009 Leave a comment

Using 2 internet browsers is an increasing trend for many people these days, as they switch between browsers for speed, security or features. The most popular browsers are Internet Explorer and Firefox, and between those 2, most people have all they need.

However for some users, more browsers are needed, whether for web design work or a craving to experiment with different browsers. Here is a snip of my Quick Launch Toolbar:

BrowsersFrom left to right: Internet Explorer 8, Maxthon 2.5, Firefox 3.51, Opera 10, Chrome 2, Safari 4

That is a total of 6 browsers. The reason I have so many is because of the work I do in Joomla for my job’s website. I like to test the pages in multiple browsers to get a feel for speed, font and layout issues as well as general usability.

I find that each of my browsers has pros and cons. Some have more features that are useful, some are faster, some have the right balance. Chrome is useful for raw speed on sites, Opera for layout issues due to its strict method of handling web standards, IE for certain sites, especially some useful Microsoft websites. My default browser however is Maxthon. It has the perfect blend of features I need to make my life easier. While not the fastest, I am more than happy with it.

For all the hype around it, I’ve never been all that huge a fan of Firefox, and as such I rarely use it. Safari rarely gets used as well, as the layout and controls feel strange to me.

Thanks to competition, IE has been forced to grow and improve, which is a good thing for those who just want to get on with the job. In turn, other browsers have been forced to be innovative to stand out, and this has lead to a win win situation for the customer really. There’s certainly never been a better time to be a web surfer.

Interesting situation at work

Two months ago, my new job saw an all time bandwidth traffic record of 151GB being used. This was an astonishing feat, as the previous high had been 90 odd, and during the June time period students were writing exams, so usage should have been quite low. Traffic was running at a constant +-300 kb/s, which was impacting our speed quite a lot. This was running right during the night, which was very weird.

After scratching our heads we were at a loss to describe how this had happened. Neither I nor my colleague had been downloading files nor running torrents. We suspected a member of staff had been doing so, or a student who messed with a staff member’s pc. We then went on a wild hunt to find this but we had no luck.

By happenstance, we got warned that we were sending spam, and after doing some detective work to find out what happened, the truth finally came out. One of our servers was being used as a proxy for spam. This particular server was set up with Squid and Dansguardian to provide internet access for students, and due to a rather messed up Netware authentication situation at work, my colleague gave the server a public IP address.

The end result was that spammers found the computer and used Squid as an open relay to send their spam. We have no clue how many messages must have passed through the server before we locked it down, but I imagine it must have been in the tens of thousands.

After locking things down, my colleague discovered that hacking attempts were taking place, as it appeared someone was trying to log in via SSH through a dictionary attack. Luckily this failed due to strong passwords, but it was still an astonishing site for me.

In all, we learnt some valuable lessons when it comes to what you let loose on a public IP. It’s happened once more since then, as my colleague was testing something and forgot to firewall the server. Luckily we caught it the next day and he shut it down.

Hopefully we don’t have a situation again like that someday. It’s embarrassing and a security risk.