I have to admit, I’m a huge fan of Movies and TV shows that have some fiction involved. Movies like “Avatar” and TV shows like “Heroes”, “Lost”, and “Flash Forward” are my favorites.

Nowadays we have come a long way to making the screen look real. Remember the first Star Wars movie (and how mind blowing it was) and looking at Avatar now (and how mind blowing it is!). Worlds apart.

If you ever wondered how it is done and are into Visual Effect’s I recommend that you check out the StarGate Studios YouTube Channel. Very good stuff. One of my favorites is below.

The last couple of weeks, I have had to use the Internet Tethering function that comes with the iPhone. During the course of this time, I made some interesting experiences that I would like to share.

Phone Calls
There is one thing I learned the hard way when I enabled Internet Tethering and wished that someone would have told me. That is, that when you don’t have a 3G coverage, like only Edge (the “E” in the upper left corner as shown in the images on the right), you will NOT be able to receive any phone calls during Internet Tethering.

Thus if you need a Internet Connection and you want to be able to receive calls make sure that you are on a 3G network.

Battery
We all know that the iPhone has miserable batterie life. When you enable Internet Tethering you have two options how you want to connect to the iPhone. One is over Bluetooth and one is with the USB cable.

For keeping your iPhone “alive”, I recommend that you connect it over the USB cable. Thus you will not drain your iPhone batterie extensively and will charge your iPhone at the same time. but there are two important things to know about this method:

1. While your iPhone is connected over the USB cable and charging it will also suck the batterie from your MacBook extensively. So, make sure that you connect your MacBook to the power outlet when you have your iPhone hooked up per USB.

2. Contrary to the above I have noticed that the iPhone is NOT being charged, even thought connected over USB. The reason for this is that as more connection you have open over the Carrier network the less the Mac is able to charge the iPhone. It is like the connection (of the USB cable) is fighting with the power, since both go over the same cable. The remedy is to lower your usage for the connection, like closing your eMail application or lowering how many times you get your eMails.

Other things…
Some of the things that I wished would be really different from a user perspective are;

… Every time I have to make a call, Internet Tethering is automatically turned off! Meaning I have to reenable it manually after the call is done. That means, clicking on “System Preferences”, then on “General”, then on “Network”, then on “Internet Tethering”, then enable it and selecting “USB”. That makes it 5 steps, 5 steps too much!

… The iPhone does not switch from Edge to 3G automatically. The only remedy I have found to this is to enable Airplane mode and the disable it again. Right after, the iPhone selects the nearby 3G network (until the next time it is back to Edge).

Nginx is our favorite web server currently as it is fast, lean and easy to configure. Performance is just outstanding and if you haven’t take a look at it.

One thing that I noticed while we deployed Nginx with Tomcat is that their default size for the buffers are very low. Don’t know why a 4K buffer size would be sufficient. If you keep it at their default size and might have a heavy duty Tomcat app then it could be that you will see error messages like:

upstream sent too big header while reading response header from upstream

The remedy for this error is to set the parameters for higher values for the proxy_buffer* parameters as we have done and now all is back to normal. Here are the current settings that worked well for us;

proxy_buffer_size   128k;
proxy_buffers   4 256k;
proxy_busy_buffers_size   256k;

Today I set out to get MySQL and PHP setup on my MacBook Pro. Since Apache2 already comes with MacOS X (mine is Snow Leopard and yours should be too!). Now, the funny thing is that I first searched on the web how to best install PHP and MySQL.

Surely, I came across MAMP (a package that gets you Apache2, PHP, MySQL and a couple libraries) in a nice one click application and some others. Being the guy who rather has things separated and controllable, I quickly shined away from those. Thought, I gave MAMP a try, but could not get MySQL to listen to anything else then the internal Apache2 server from the MAMP package (but guess that is another story and I’m really not doing this the first time.). Anyhow…

I then looked into getting Apache2, MySQL and PHP with MacPorts. Thought MacPorts has proven to be perfect in such circumstances, I had a hard time (and it took very long) to get this setup up and running. I’m sure, some of you have had successful installs and all works great, but at the end it did not work for me. There are even more instructions to get PHP running, with a lot of tweaking and such, but to be honest in the end…

Really the simplest and most straightforward method to get Apache2, MySQL and PHP running on MacOS X is;

MySQL

Now, this is really no brainer. All you need to do is to go to http://www.mysql.com and download the recent release. Within the download image you will find a nice installer and Preference pane which lets you start/stop MySQL. If you want to go all GUI, then also download the GUI tools from MySQL.

Apache2/PHP

The probably easiest of it all. Since MacOS X already comes with Apache2 and PHP all you need to do is to enable it. Thought, PHP is disabled in the httpd.conf, all there is to do is to edit httpd.conf and uncomment the mod for the php library.

That’s it!

Nothing to install, (almost) nothing to configure. Simple and easy.

SugarCRM is a good open source CRM, but the overwhelming functions and navigation makes it “sometimes” hard to really get to the one thing you want to do. In any case, it does the job well. Apart from that, I just came upon this error message within SugarCRM:

Warnings: Inbound Email cannot function without the IMAP c-client libraries enabled/compiled with the PHP module. Please contact your administrator to resolve this issue.

This definitely means that PHP is missing some mail libraries, but the message to compile PHP is kinda scary, isn’t it? Luckily, if you are using Ubuntu all you need to do is to issue an “apt-get” command and you are rolling. So here we go:

apt-get install php5-imap

This will install everything for you, make sure to restart PHP (restart Apache or the FastCGI).

We just moved a whole bunch of servers to a new hosting center and moved from CentOS to Ubuntu (server) and Apache to Nginx (more on this in a later blog post).

While we migrated mostly everything without problems we were confronted with the problem that our SSL certificate gave us an error message of the form:

“The certificate for this website was signed by an unknown certifying authority”

This was rather strange because the same certificate worked with Apache just fine. After some time and searching for a solution we found that we had to tell Nginx to use the SSL Chain file as well. The only problem is that Nginx does not have a explicit parameter like Apache has. In Apache the SSL config looks like this (we use a GoDaddy certificate):

SSLEngine On
SSLCertificateFile /etc/httpd/ssl/youcert.crt
SSLCertificateKeyFile /etc/httpd/ssl/yourkey.key
SSLCertificateChainFile /etc/httpd/ssl/gd_bundle.crt

Now, in order to get this working in Nginx you need to append the “gd_bundle.crt” to your crt file, which is quite simple with the following commands (do a backup of any files before doing this!):

cat gd_bundle.crt >> yourcert.crt

Then simply restart Ngnix and all is back to normal (but just really faster with Nginx then with anything else:-) ).

Just been going trough a lot of reconfiguration lately and today finished configuring a new server. While testing the mail function we saw in the mail logs the following lines:

javax.mail.MessagingException - 501 Syntactically invalid HELO argument(s)

First we thought, it is the application server or sendmail/exim not being properly configured. But as we soon found out, one simply needs to have a valid hostname set for the server. In other words, this error is commonly caused by the hostname of the machine being wrong compared to what the mailserver expects. Java mail does a getHostName and uses that in the HELO.

And just in case you simply set your hostname with “hostname domain” it will not persist on the next reboot. In order to keep your new hostname you will need to change it in the hostname file itself, as in:

sudo  vi /etc/hostname

Do a reboot and all should be good.

We just moved some of our subversion repositories to a new server and with it changed the URL’s. Now, in order to change any existing checkout version to grab updates from the new subversion server we issued the simple “switch” command from subversion as in:

svn sw svn://svn.domain.com/trunk .

The problem with this was that the system complained with:

svn: 'svn://svn.domain.com/trunk'
is not the same repository as
'svn://svn.newdomain.com/trunk'

The correct syntax to relocate any existing checkout copy is to use the “–relocate” switch as in:

svn sw --relocate svn://svn.domain.com/trunk svn://svn.newdomain.com/trunk

And we are back in business…

CentOS, being a “legal copy” of RedHat, as good as it is, comes with some really outdated libraries. This has caused many, including myself, to find way how to bring latest code releases into CentOS. Be it by alternatives repros or compiling the packages.

Now, I don’t know how I could overlook it, but I just found out that the CentOS team offers a CentOS-Testing repro. Once installed you will get the latest library updates as well. Since it is based and supported by the CentOS guys, I figure it is the safest way to get the latest updates.

Simply add the following at /etc/yum.repos.d/centos-test.repo:

[c5-testing]
name=CentOS-5 Testing
baseurl=http://dev.centos.org/centos/5/testing/$basearch/
enabled=1
gpgcheck=1
gpgkey=http://dev.centos.org/centos/RPM-GPG-KEY-CentOS-testing

Save it and do a yum check-update and you will get all the good yummies. Make sure that you don’t install something carelessly on a production server, right…

Mind you, I’m no PHP guru and I only have PHP installed on our server because of our Wordpress blogs. that said, I was facing an ugly PHP error today and somehow we could not load the Wordpress admin pages anymore of it. The error was:

PHP Warning:  Module 'fileinfo' already loaded in Unknown on line 0

After searching for a solution I thought it would be best to update PHP along the way. Thus I found this nice description on Webtatic Blog which describes how to update to the latest PHP version on CentOS 5.x (since the default repro only brings you 5.1.6).

Low and behold, after updating to the latest PHP version, it will give you 5.3.1, the error was gone and Wordpress Admin pages are back to normal.