Wednesday, February 25, 2009

Parsing HTTP Responses

Just so I don't have to remember again, in order to seperate a header from the body of a http response, in C:

char* endOfHeader = strstr(buf, "\n\r\n");

Notice the \r, that is a carriage return, something that Linux/unix doesn't care much about, but is used more in Windows. I couldn't find any websites to help with this.

Tuesday, February 17, 2009

No devices: No Screens Detected.

Had a problem today with the no screens detected on the new Viz wall computers. Solved it by first installing the Nvidia binaries straight from their website, and then allowing X configure itself:
X -configure
cp /etc/X11/xorg.conf

After it configured itself, starting X was only a matter of:
init 5

Then, I had a problem with getting 3 seperate X screens configured to be on top of each other. This was to prove that it was possible, for use on the Viz Wall. I copied over a working xorg.conf from another tile wall with the same configuration, but that one didn't pick up both of the monitors on the single card. There was an error involving not having DFP-0 and DFP-1 setup to be configured. So, after much work, I got the cards to recognize the DFP-0 and DFP-1 as seperate screens (ie. in different screen declarations).

The Xorg.conf (Google Docs)

Moral of the story, Nvidia-Settings is very good at figuring out how to configure monitors.

Thursday, February 12, 2009

Fuse DFS Error

So, today I was having problems getting the fuse-dfs to work with my cluster. I was an error compiling fuse for my kernel (2.6.18-92.1.17.el5). It seems that yum has stop providing this kernel, and it's headers (yum install kernel-headers wanted to install a newer version).

To solve this problem, I simply compiled with a older kernel-headers already installed on the machine (2.6.18-53.1.13.el5). To do this:
./configure --with-kernel=kernel-dir && make

The kernel module is in the directory kernel/. Modprobe will not work, instead use insmod.
cd kernel
insmod fuse.ko

This way is probably not the best way to do something like this, but it works.

Tuesday, February 10, 2009

Fish Monitoring

After a few years of working on the Fish, I have finally published a video of them running, so that they could be demonstrated easier.

Monday, February 9, 2009

Viz Wall Computers

Today I put together a computer spec for the viz wall we are building here at RCF.

Here's the link to the page: