Dec 022010

Linux software RAIDs are very useful, but a lot of people seem to have trouble when they need to boot from an array. They just don’t grok Grub well enough to get it installed properly. It’s especially common to see everything work fine until one of the drives fails. Then they realize that Grub was only installed on one of the disks in the array (the one that failed) and it doesn’t boot anymore. The correct process isn’t tricky, but you have to know the right commands.

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Nov 222010

A fair number of users come to searching for “linux remote clipboard”. I find this interesting, as I’ve never had a use for such a thing. I do not know your use case, but I think it’s possible you’re not considering some of the more powerful options available. There are a couple remote clipboard software packages for you to consider, although you may end up having to pay a license fee. You may also be going about the solution in the wrong manner, so I’ll suggest some alternatives.

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Aug 182010

RSH and RLogin aren’t that difficult to set up once you’ve gone through the man pages and done the installation a few times, but those first few times are a pain. They’re old and insecure, but still frequently used on small compute clusters. I get the impression that a lot of beginners get stuck fiddling with them for hours or days. They’re quite possibly the biggest stumbling block one faces when setting up a compute cluster by hand (setting /etc/hosts.equiv, setting /root/.rhosts, making sure the right flags are being sent to the rsh and rlogin daemons, etc).

Both use the xinetd daemon, which is one of those carry-overs from ancient Unix. Plenty of old Unix stuff made sense, but inetd is backwards. To enable a service, you set disabled = no. To disable a service, you set disabled = yes.

Putting double negatives in your configuration file is not a good idea. When a setting this basic takes a couple seconds of thought, you’re doing it wrong. Were it something more complicated, administrators would be selecting the wrong option all the time.

Oct 082009

I’m thankful to work in one of the most Linux dominated fields in the industry. But the rest of the world still uses Windows all over the place, so I do have to use it as part of my job. I recently made my life much better by installing Windows under Ubuntu Linux using VMware. Now the couple Windows apps I have to use are relegated to one virtual desktop on my Linux box.

The setup was mostly painless, but I did run across some very frustrating behavior with a couple of the Windows applications.

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Oct 062009

There are a lot of user interface inefficiencies that we’ve all been forced to get used to. Moving and resizing windows is definitely one of them, as you have to carefully position the mouse cursor over a tiny section of a window.

However, there’s no need for Linux users to do this. X-Windows supports moving and resizing windows by clicking and dragging on any portion of a window – the mouse cursor can be over any portion of the window, no matter what’s underneath.

Here’s how:

  • To move: Hold down ALT while clicking and dragging with the left mouse button
  • To resize: Hold down ALT while clicking and dragging with the right mouse button

You’ll find that even though it’s a small tip, your work will be just a little more efficient.

Sep 242009

I’ve had to use VNC many times to bridge the gap between Windows and Linux systems. It’s not always the prettiest or most efficient way to get things done, but it can be quicker and less complex than virtualization or X11 through Cygwin. One stumbling block in my workflow has been the clipboard – you become so accustomed to moving data from one application to another that you really miss it when the functionality is missing.

Fortunately, there are VNC clients that will take care of this for you. I typically choose TightVNC, as it offers very good performance (including some accelerated Windows drivers) and is available for a variety of platforms. The details below may be specific to TightVNC.

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Mar 012007

The user interfaces on computers have not really gone through that many revisions. I’m certainly not a historian of all computer systems, but the basic idea is that computer use became much easier as the interface became more graphical and ‘user friendly’. I still must question how effective modern interfaces are, though.

Suppose you have a certain phone manufactured by Samsung with awful software that supposedly combines the functionality of an iPod and a cell phone. Although this phone will play MP3 songs, it will only play them if they are a very specific type of MP3, the filename doesn’t contain any special characters and the filename is 32 characters or shorter. How do you copy your music collection onto this phone?

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