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showing posts tagged with 'computer'
by lunarg on April 29th 2007, at 19:40
There are two things you need:

A bootable linux LiveCD, preferrably Knoppix, but any other distro with all basic linux tools will do.

Some knowledge on how to use commandline based programs (and perhaps some knowledge with linux in general).

First, make sure to boot with your LiveCD. You won't need to boot entirely into the graphical interface.
For Knoppix, the boot: commandline would be something like:

boot: knoppix 2 lang=your-keyboard-layout vga=normal

You can leave out the vga=normal to use framebuffer instead of plain text mode. Replace your-keyboard-layout (keyboard layout) with your country code: for Belgium (azerty), this would be lang=be; for standard US (qwerty), use lang=  ...
by lunarg on April 28th 2007, at 00:46
In short: the kernel frequency is the number of interrupts (IRQs) handled by the kernel per second. Like most applications of frequency, it's also expressed at Hz (hertz).

A more sound explanation of interrupts can be found here, but it basically boils down to this: an interrupt is generated each time an event on a piece of hardware (in the most elementary way; this includes your keyboard for instance), and requires the necessary CPU time to handle that event. This is called interrupt handling.

Now, because the kernel directly interacts with all the hardware around, it's vital to have it handle interrupts; actually, it's the kernel that handles interrupts, by using the CPU.

Very simple: t  ...
by lunarg on April 28th 2007, at 00:37
If you happen to have keyboard trouble when you SSH with PuTTY to a Debian system, you might want to read on.
With trouble, I mean one or more of the following symptoms:

Numeric keypad not working, even with numlock enabled/disabled

Home/End keys not working as they should

Function keys not working as they should

Other weirdness concerning keyboard...

We've figured out a possible solution to the problem. It has been tested (and used) extensively by my and a collegue, and have found it working perfectly on Debian Woody and Debian Sarge.
It may be possible that these settings also work on other distros having similar problems. If it does, please let us know so we can add it to the article  ...
by lunarg on April 28th 2007, at 00:32
The bliss of dual core can quickly turn to a curse when you're running applications that weren't build to handle multiple CPU's.
Although one could set affinity with windows task manager, the application often goes down before one could alt-tab to set it, or sometimes, the application doesn't even start at all.

A quick search on the web has brought me on a forum thread, where they were talking about RunOnProcessorExplicit, or in short: ROPE.
ROPE is a very simple tool, that allows you to set affinity directly at the start of an application. This circumvents the need of using windows task manager and moreover, allows you to change shortcuts accordingly, so you won't have to remember to set a  ...
by lunarg on April 28th 2007, at 00:18
If you are blessed with ssh access to your webhosting, then a world of goodies opens up. One of these is rsync. When installed on your webhosting (which usually is), you can use this instead of ftp to maintain your website.

Rsync is mainly used for syncing two file structures (directories and subdirectories) together. It works by comparing the two structures and check out each directory and files on modified date and time, but also content of the file (using hashes).
While mostly used for backup, this thingy is very handy when maintaining a website. Rather than figuring out which files need to be copied, rsync does it all for you with a single command.

rsync -e ssh -rltDv <local website  ...
by lunarg on April 28th 2007, at 00:16
When you're running Windows on a system with 4GB RAM, you might have noticed that the entire amount of RAM is not detected (it's somewhere around 3.6GB). This is because of the way HIGHMEM (4GB and up) is handled.
Fortunately, there is a way to solve the problem, allowing the full use of 4GB...

A solution to our problem is by forcibly enabling Intel's Physical Address Extension (in short, PAE). This is done by taking the following steps:

Locate the boot partition (this usually is C: but could be something else): it contains the bootloader files such as ntldr, boot.ini, etc.

Open the boot.ini file, which is in the root of that partition (e.g. c:boot.ini). Note that you might need to change  ...
by lunarg on April 27th 2007, at 23:56

Copy the following code into your ~/.screenrc
Or if you want to add the statusbar globally, add it to /etc/screenrc.

# An alternative hardstatus to display a bar at the bottom listing the
# windownames and highlighting the current windowname in blue. (This is only
# enabled if there is no hardstatus setting for your terminal)
hardstatus on
hardstatus alwayslastline
hardstatus string "%{.bW}%-w%{.rW}%n %t%{-}%+w %=%{..G} %H %{..Y} %m/%d%C%a "

When running screen, the result should look similar to this:

by lunarg on April 27th 2007, at 23:50
During the installation of a device (hardware, or a software emulation driver, such as OpenVPN's TAP-Win32 driver), you get the following message:
Quote
The system cannot find the file specified.

After that, it goes into a hardware detection loop, meaning it finds and tries to install the same hardware again and again until the cows come home.

Windows 2000 and XP has a bug that it cannot properly install drivers using INF-files, when the RunOnce registry key is missing from the following location:

HKEY_LOCAL_MACHIN\SOFTWARE\Microsoft\Windows\CurrentVersion

This key is often used by installers to execute post-reboot scripts and programs, but when these run, they sometimes inadvertently de  ...
by lunarg on April 27th 2007, at 23:41
When attempting to send a message which is too large for your mail server, it may become stuck in the outbox, unable to delete it, because Outlook says it has already started to send the message.
If this happened to you, there are two things to try...

Try setting Outlook in offline mode:

In the menu, click File, then Offline

Wait about a minute or so, then close and reopen Outlook

If everything went well, you should now be able to delete the message from the outbox, or at least, move it to another folder before attempting to delete it.

When this worked, disable offline mode: click on File in the menu, then again Offline

Finally, restart Outlook and everything should be well again.

If   ...
by lunarg on April 26th 2007, at 22:34
Every now and then, one might need to resync one or more disks that were in a linux software RAID array. This usually is not a problem at all, but once in a while (in particular on SATA controllers), the resync takes up a lot of system resources, regardless of the fact that the resync doesn't exclusively uses bandwidth (i.e. it only uses the free available bandwidth).
In this case it may be necessary to cap the maximum resync speed limit to a lesser value, so a bit of bandwidth becomes free again, seriously reducing the I/O load.

Changing the maximum and minimum speed limits is easy. Like most system things, this is done by echoing the desired speed to a file in the /proc filesystem:

To se  ...
by lunarg on April 23rd 2007, at 23:33
Spam nowadays is a real pain. While linux users are fairly safe against most common viiri and spyware, spam mail affects everyone.
While there are many spamfilters out there, I've found that only one is pretty effective, on the long run as well. This guide provides a solution to implementing this filter into KMail for local scanning, filtering and retraining.

A working KMail configuration for scanning and retraining spamfilter with POP3 accounts (IMAP is not supported because mail doesn't really get "downloaded").

A DSPAM 3.6.x using the hash_drv, with training data stored in the user's homedir (~/.dspam)

KMail (of course)

A sane build environment (gcc and co)

Superuser access (for DSPA  ...
by lunarg on April 12th 2007, at 17:36
Uninstalling a managed Symantec Antivirus is no picknick: it requires you to enter a so-called uninstall password, one which of course you never had to enter, or otherwise know about...

After numerous attempts of inserting the local administrator password, the domain admin password, the Symantec Control Center password, etc., I had nowhere to turn but to Google.

After a few searches, I stumbled upon a site explaining steps on how to remove the thing. Preparing myself for a lengthly uninstall process with many steps, the site mentioned between the steps, to try an uninstall using Add/Remove programs in Windows, and if it was a managed install, to use the password symantec.
As I didn't feel   ...
by lunarg on April 3rd 2007, at 17:28

Found this article to be useful while installing a Gentoo in a virtual machine for VMware:
http://gentoo-wiki.com/HOWTO_Install_Gentoo_on_VMware_in_Windows_NT/2K/XP

I found the kernel configuration portion particularly useful, especially since I managed to enable every SCSI controller and network adapter accept the one I needed.

by lunarg on March 28th 2007, at 11:10

If VMware Server Console doesn't work on your Ubuntu 6.10 Edgy install, here's what to do.

If after installing, the console does not launch, but instead takes up 100% CPU until the end of days (or until you kill it), try starting the console with this command:

LD_PRELOAD=/usr/lib/libdbus-1.so.3:$LD_PRELOAD vmware-server-console

This fixes some yet to be resolved issue around shared libs.

by lunarg on March 26th 2007, at 21:12
In my trial runs of various filesystems, I decided to convert the data partition of my server/devel pc from ReiserFS to XFS...

Steps are quite short. Since convertfs is highly discouraged, I did it the long way:

I used dar to pack the data partition and moved it to external storage.

Did mkfs (read below).

Extract the thing back to the data parition.

Since XFS is a bit sluggish, I followed the forum thread at http://forums.gentoo.org/viewtopic-t-488215.html to speed things up a bit. I used the following for mkfs:

mkfs.xfs -l internal,size=128m -d agcount=2 /dev/sda6

The explanation for all these parameters can be found in the forum thread I mentioned earlier.

This allows for a bit mor  ...
by lunarg on March 26th 2007, at 20:48
Did (again) a reinstall of my laptop to get rid of all the funny unused packages and software (which was quite needed). Well, the other real reason was for me to test out a new filesystem. While my original plan was to go with XFS, I decided to try on Reiser4.

Installation was not a real easy task: while Gentoo can be installed through virtual any LiveCD (yeah Gentoo), there are not much livecd's out there with new enough (2.6.17+) reiser4 support, and even less cd's that are on top of that 64bit. In fact, I found none.

Since it's impossible to chroot into a 64bit system when running a 32bit kernel, I had to pull some stunts to get my reiser4 installed on Gentoo.

I used these resources:

  ...
by lunarg on March 26th 2007, at 20:08
Apparently, there's no package for MS-SQL support in Debian or Ubuntu. Why this is, is not very known, in particular since there is MS-SQL support in PHP4 and PHP5.
I found the following steps somewhere on the internet.

The following was tested on a Ubuntu 6.10 Edgy, but will probably work on others as well.
Also, whenever I refer to php5, it could well be replaced with php4, which I've tested as well.

First of, make sure the necessary build tools are installed:
# apt-get install build-essential debhelper

It's possible more tools are needed, depending on which ones have already been installed, but basically, if you can compile other packages from source, you should be good to go.

Next up  ...
by lunarg on March 16th 2007, at 17:32

Because of relocation of my webhosting to another server housing, this site (and others on that particular server) will be unavailable.

The relocation is planned on Thu 15th February around 4am. Expected downtime should be about 2 hours (depending on traffic ;-) ).

by lunarg on February 11th 2007, at 19:50
Installing Internet Explorer was never so easy with IEs4linux, a script that does all the work for you. Download and try it now: http://www.tatanka.com.br/ies4linux/.

It's really easy, but here's how I did it. Note that the instructions are also on the website of IEs4linux.

First, make sure the required software is installed:

wine: very obvious, you need this to run the installed IEs;

cabextract: required to unpack the CAB files that get downloaded.

You don't need to backup your current ~/.wine/ directory, as IEs4linux created a separate profile for the IEs. If you do happen to need IE for your other apps, it's best to start with a clean profile, as a profile with other apps installed   ...
by lunarg on February 10th 2007, at 19:06
Was upgrading a bit on my laptop (amd64), and this included udev and baselayout.
After a reboot, my whole system did funny things. All was retraceable to one thing: the system was automatically loading modules as it pleases, which caused all kinds of problems...

I have a pretty custom configured system concerning hardware.
By default, I only use wireless, and thus don't load the local netif modules (Realtek 8139) and definitely not the IEEE1394 (Firewire) link, as I very rarely us this for networking (and when I do, it's mainly for high-speed p2p transfer - no I don't have gigabit network).
Secondly, I have both my onboard sound card, as well as my Audigy 2 PCCARD configured. Naturally, the  ...
showing posts tagged with 'computer'
 
 
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