Tuesday, December 27, 2011

Minecraft on Ubuntu; Finding and fixing errors

Now that Minecraft is outta beta, at version 1.0.0, it's time to get it running on Ubuntu with all the mods. The standard 1.0 version runs fine in Ubuntu 11.10, but I'm having some trouble with ModLoader, and therefore all the mods that in turn depend on ModLoader.

My first task is to run Minecraft without any errors. To start I installed and ran Minecraft on Ubuntu using Alloc's Easy Minecraft Installer. This creates a handy desktop icon on the account I used to run the install script. Of course, using this icon precludes seeing any error output from the program. Once you've installed Minecraft using the script, you can copy the icon file to any other desktop directory, and then update the command line with the name of the new home directory. Then, set the properties of the shortcut file to "executable"

To review the error output, I open Terminal and paste in the command:

java -jar /home/[myhomedir]/.minecraft/minecraft.jar

where [myhomedir] is the name of my home directory.

Or, you can use the tilde ("~"):

java -jar ~/.minecraft/minecraft.jar

This works in Terminal, but not in the destop icon command field.

My first error is:

GL ERROR Pre render 1281: Invalid value

To resolve this error, in ~/.minecraft/options.txt, I set advancedOpengl:true (this was originally false)


Now I get:

Loading: net.java.games.input.LinuxEnvironmentPlugin
Failed to open device (/dev/input/event3): Failed to open device /dev/input/event3 (13)

...

down to

/dev/input/event0

The fix for this, from the World of Minecraft support forum, is the following Terminal command:

 sudo chmod go=u /dev/input/event*

This worked; I now see:

Loading: net.java.games.input.LinuxEnvironmentPlugin
Linux plugin claims to have found 4 controllers

So, no errors!

Wednesday, May 25, 2011

Area51 is ill, won't boot Windows or Ubuntu

Area51 won't boot up correctly, and the behavior is quite odd. I was able to boot off of my handy Ubuntu 10.10 disk, however, which rules out most problems with the motherboard, RAM, video, networking -- it looks like there's some problem reading the hard drive. I want to do some troubleshooting on the hard disk partitions, since that seems to be the most likely source of the problems. This is right after I ran that disk utility, but the computer booted since then. Fortunately, since I can get onto the Internet, I can log my work right here on this blog. - Posted using BlogPress from my iPad

Thursday, May 20, 2010

Connect to a Mac OS X Screen Sharing Client with Ubuntu's Remote Desktop Viewer

On my Apple blog I describe how to connect to Mac OS X computers with Ubuntu's Remote Desktop Viewer. Ubuntu's

Remote Desktop Viewer (Applications : Internet : Remote Desktop Viewer) is really Vinagre, A VNC Client for the GNOME Desktop. This VNC client supports connections to Mac OS X using the Mac's Screen Sharing service, Apple's built-in implementation of the VNC server protocol.
The post includes step-by-step instructions on how to configure the Mac Screen Sharing server, and how to establish a connection with Ubuntu's Remote Desktop Viewer.

Saturday, March 27, 2010

Webmin on CentOS

We use CentOS for our web servers, and favor Webmin as a way to administer our servers. To install Webmin via yum on CentOS, follow these steps as root or sudo, from the command line (via SSH or at the console). These steps will also work for RedHat servers.

Configure the Webmin repository and install

Webmin is not available via yum in the default CentOS repository. Follow these steps to add the Webmin repository (repo) from Webmin.com.

  1. Create and edit the repository file # nano /etc/yum.repos.d/webmin.repo
  2. Add the [Webmin] section (listed below) to the new repository file
  3. Save the new file
  4. Import the public key: # rpm --import http://www.webmin.com/jcameron-key.asc
  5. Install webmin: # yum install webmin

Open the Firewall

If your server is protected by a firewall, you won't be able to access Webmin until you open port 10000. Use these steps on CentOS

  1. Backup the current firewall settings: # cp /etc/sysconfig/iptables /etc/sysconfig/iptables.bak
  2. Install the Red Hat firewall configuration tool # yum install system-config-securitylevel
  3. Run the firewall tool: system-config-securitylevel
  4. Select _Security Level:_ *Enabled*
  5. Click [Customize]
  6. Check incoming ports to allow (probably SSH, WWW, Secure WWW, and FTP)
  7. _Other Ports_ 10000:tcp
  8. Click [OK]

This will save your new settings and reload the firewall. You won't have to use this command line firewall tool again, as now you can use Webmin to configure the firewall.

Test Webmin

Now that you've installed Webmin and opened the Webmin port, test it out. Open your favorite brower and type your server's IP address followed by :10000, like this:

168.192.1.1:10000

The Webmin login screen should appear. Log in with your root credentials. It's a good idea to set up another Webmin user so you don't have to use your root credentials

Webmin repo section

[Webmin]
name=Webmin Distribution Neutral
baseurl=http://download.webmin.com/download/yum
enabled=1


Saturday, February 20, 2010

Damn Small Linux (DSL)

I'm trying to help my friend fix his Dell OptiPlex GX400, which is running Windows XP Home, and is probably owned. It only has 128 MB of RAM, and it turns out this particular model uses expensive 128MB PC-800 Rambus RIMM for Dell RAM Memory. So, it doesn't make sense to buy a chip, really, and none of my spares will probably fit.

Instead of throwing hardware at the problem, I looked at Damn Small Linux (DSL information) To burn a CD of Damn Small Linux, Download the ISO and then burin it to a CD, in Windows, with InfraRecorder (GPL).

DSL is based on Knoppix, but is stripped down to a bare bones set of Debian packages. As promised, booting DS from the CD transformed the slow, almost unusable computer into a speed demon. Plus, DSL shows system resource use right on the desktop, and we could see that it was hardly using any RAM -- less than 20% of 128 MB.

Now all we have to do is figure out a way to save the configuration, and configure networking.

Thursday, October 15, 2009

Perl & PHP Shell Scripts

Writing scripts in bash is lame. I'm not the only one who thinks so: Shell Script Language – Use Perl, Not Bash | LinDesk

From the post:

Advantages of using a Shell Language

  • Its supported in even the tinest linux distros – even in embedded systems.
  • Its the method preferred by the majority – I hope this will change soon.
  • Command calls look more natural in a shell language.

Advantages of using a High Level Language

  • Better Code
  • Easy to maintain
  • Faster development
  • Libraries provide a lot of functionality
  • Easier to port to different platforms.

PHP Shell Scripting

Want to get busy slinging code? Start here: