SimpleSAMLphp with WordPress on OpenShift

These are the steps that I used to get SimpleSAMLphp running with WordPress on OpenShift.

First, copy the files up to the server and decompress them.

$ rhc scp MYAPP upload simplesamlphp.tar.gz app-root/data
$ rhc ssh MYAPP
$ cd app-root/data
$ tar -zxf simplesamlphp.tar.gz

Then, link it to a public WordPress directory e.g. uploads

$ cd uploads
$ ln -s ../simplesamlphp/www/ saml
$ cd ../simplesamlphp

Then, just configure SimpleSAMLphp as usual.

The only key thing to note is that the baseurlpath needs to be configured with a FULL path name. For some reason, SimpleSAMLphp was unable to detect that it was running behind a reverse proxy.

Ubuntu 12.04 LTS with Missing Dota2 Textures

There is a pretty well known bug with Dota2 under Linux on Intel graphics hardware. Essentially, models textures are missing as can be seen from the screenshot below:

I had at first tried installing lts-raring hardware enablement but that did not solve the problem and created new ones with my hardware. According to the bug-report, the problem was solved in Mesa 9.1.5 but lts-raring came with 9.1.4 only.

So, I downgraded back to lts-quantal and looked for another solution.

In the end, all I had to do was to add a 3rd party PPA to solve the problem:

# apt-add-repository ppa:glasen/intel-driver
# apt-get update
# apt-get -y dist-upgrade

This would install the Mesa 9.1.6 and Intel drivers, which solved the problem.

Now, I get to experience Dota2 in all its glory!

Quantal to Raring Upgrade

I faced the same Quantal to Raring upgrade problem on Ubuntu 12.04 LTS with Hardware Enablement as reported here.

In order to get it to work, I had to remove Xorg for Quantal then upgrade everything to Raring. I did this from the command line terminal:

$ service lightdm stop
$ apt-get autoremove xserver-xorg-lts-quantal
$ apt-get --install-recommends install linux-generic-lts-raring xserver-xorg-lts-raring libgl1-mesa-glx-lts-raring
$ apt-get install linux-tools-lts-raring

That was it. Upgraded to LTS-Raring hardware enablement kernel and Xorg.

PS: The only issue with this upgrade was that I lost back-light control on my XPS13 laptop as reported here.

RTL8192CU Issues

The TL-WN725N nano dongle is a cheap way to get 802.11n wireless connections up. However, the RTL8192CU chipset has issues under Linux.

After a whole day of trouble-shooting and digging, the best solution that I came to is this: use the driver supplied by Realtek!

First, the built-in kernel driver rtl8192cu needs to be disabled.

$ echo "blacklist rtl8192cu" >> /etc/modprobe.d/rtl8192cu.conf

Next, download, unzip and build the Realtek driver. Just run the included script.

$ bash

That’s it! All other configurations as per usual.

HP ML110 G7 Fan Noise

I love the fact that HP sells servers retail in Malaysia. It’s so convenient to just pick one up from the local store instead of going through all the procedures of issuing a PO etc.

However, the ML110 G7 that I picked up a couple of weeks ago, has one rather major problem – its fans run at full speed all the time.

Granted, the server room in the office is not air-conditioned but I keep the windows open for natural ventilation. The temperature itself is just normal room temperature, as confirmed by the air-intake sensors of the server.

Although the server is the main work-horse of the entire office, it’s a small office and the work-load isn’t heavy. Most of the time, the load average is only at about 11% with the CPU clocked down to the slowest possible speed.

So, it was a pain to find that the three fans were running at a 100%:84%:10% ratio all the time. There’s no real reason to do this since the temperatures are all within a very reasonable range.

Now this wouldn’t be too much of a problem except that the fans running at those speeds sound like a jet plane taking off. It’s a small office and the noise is noticeable above the air-conditioner’s even though it sits in its own room.

It took me a little bit of sleuthing and experimenting but the final trick that did it was to simply upgrade both the BIOS (10-Aug-2012) and ILO (1.50) firmware to the latest versions.

Now, the fans only hover at a very reasonable 78%:66%:11% ratio on a very hot afternoon.

Disappearing User Dirs

My current setup places the user’s home directory in a glusterfs volume. This causes problems with a recent Ubuntu 12.04 update and a user’s XDG user directories get reset to $HOME during the X11 login. It only happens for X11 logins and not shell/ssh logins.

A quick fix to this issue is to do the following:

  • Make a copy of the existing X11 session XDG configuration.
  1. # cp /etc/X11/Xsession.d/60xdg-user-dirs-update /etc/X11/Xsession.d/61xdg-user-dirs-update
  • Edit the copy to force the user directories to their defaults.
  • # nano /etc/X11/Xsession.d/61xdg-user-dirs-updateif [ -x /usr/bin/xdg-user-dirs-update ]; then
    /usr/bin/xdg-user-dirs-update --force


PS3 Aspect Ratio Problem

Español: Logo Vectorial de YouTube
Español: Logo Vectorial de YouTube (Photo credit: Wikipedia)

After recently updating my PS3 firmware, I noticed that there was a new button in the menu – TV channels. The only option available at the moment seems to be YouTube. So, I downloaded the 22MB update and checked it out.

But for some reason, the new YouTube application ran at the wrong aspect ratio on my system. It was running in a 4:3 ratio instead of 16:9 HD ratio. My television is capable of Full-HD and I nominally had my PS3 configured to run at 1080i. Everything else seems to work fine including Bluray, games and normal video playback.

So, after a little investigation, turns out that the YouTube app runs at 720p and I had 720p disabled in my PS3 display settings. Enabling the 720p option in my display settings allowed the YouTube app to run correctly. It was odd, trying to watch 16:9 HD videos on a 16.9 TV with black horizontal bars.

So, I’ll start using the PS3 for streaming YouTube from now, on trial.