Quick Hacks 8.1 III

Summary:

• Performance Gain With Enterprise Kernel
• Problems with '/dev/cdrom'
• 'Euro' Symbol Support In KDE Flaky
• No Internet Connection On LAN Machines

Section index - KB index

'Quick Hacks 8.1' are a loose collection of work arounds, quick fixes and tips for Mandrake Linux 8.1. They are meant as a supplement to the official 8.1 errata page, not as a replacement.

You are invited to contribute your 'Quick Hacks'? as well1.1

Performance Gain With Enterprise Kernel

Mandrake Linux user Gerard H. Gilbert reports:

Recently I had to do kernel upgrades on several computers running GNU/linux OS's. I thought this would be a good time to experiment a little on two of the noncritical backup computers.
One box is a 433 socket 7 CPU on an amptron mother board. The other is a slot 1 333 on a Intel motherboard. Both of these machines are considered as having an i686 architecture both are single CPU boards with about 128 megs of ram.

I decided to try out the enterprise kernel on both, why not? To be honest with every one I didn't think they would even boot off the enterprise kernel1.1
Much to my surprise when I booted the slot 1 333 not only did it boot up but there was a noticeable difference in the boot up speed. So I installed the enterprise kernel on the 433 socket 7 and the same thing happened. It took about one third less time for boot up.

Still I didn't believe I could get such improvement in performance from changing to the enterprise kernel. My next step was to benchmark the machines my way, by running the seti at home program. With the default kernel GNU/Linux Mandrake 8.1 my slot 1 333 on a Intel motherboard took twenty four hours to complete one work unit, it now puts out one and a half work units for the same time period using the enterprise kernel.

section index

Problems With '/dev/cdrom'

Problem:

Applications like CD players complain about there being 'no device' or 'no disc' although there is a CD in the drive.

Cause:

The cause is this entry in '/etc/devfsd.conf':

LOOKUP          ^cdrom$         CFUNCTION GLOBAL symlink cdroms/cdrom0 $devpath

It creates a '/dev/cdrom' symlink which points to (the non-existent) '/cdroms/cdrom0' device file instead of '/dev/cdroms/cdrom0'.

Solution:

Change the above line as 'root' to

LOOKUP          ^cdrom$         CFUNCTION GLOBAL symlink cdroms/cdrom0 cdrom

and delete '/lib/dev-state/cdrom' (also as 'root'):

rm -f /lib/dev-state/cdrom

Reboot. The '/dev/cdrom' symlink should now point to the proper location.

section index

'Euro' Symbol Support In KDE Flaky

Problem:

Although the 'ISO8859-15' charset is set in 'Personalization - Country & Language' in KDE's control center and in the individual applications, no 'Euro' sign (€) can be entered in KDE applications. 'Konqueror' displays the sign on some pages, on others not. GTK+ applications however usually work fine if an 'ISO8859-15' charset is set.

Cause:

The root of this problem lies in a KDE locale bug, which also describes a (possible) solution. Strangely enough, this problem doesn't seem to hit all systems it theoretically could, and the solution doesn't seem to work on all systems either.

Solution:

Edit '/etc/sysconfig/i18n' as 'root'. You will find a line like

LANG=xx

LANG=xx_XX@euro

LANG=xx_XX@euro.ISO8859-15

Log out of X and back in again, and with some luck you should be able to enter the € sign in KDE applications. Reports indicate that it should work for Italian, I've tried it for German, but with no luck.

Displaying the Euro sign on web pages is a different kind of animal. If the website defines in its header the ISO-8859-1 charset as the standard charset, 'Konqueror' will not display the Euro sign, but a question mark instead, whereas Galeon or Mozilla do not suffer from this problem. If you are using 'Konqueror' now, you only see the Euro sign in this article, because I changed the default charset of this page to ISO-8859-15.

There seems to be no way of getting a statically linked version of Opera 5 for Linux to display a Euro sign.

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No Internet Connection On LAN Machines

Problem:

On machines configured to be part of a LAN (Local Area Network), no working Internet connection can be established ('no route to host').

Cause:

It seems that under certain circumstances, the 'draknet' utility sets the

GATEWAY

Solution:

Edit '/etc/sysconfig/network' as 'root' and delete the

GATEWAY

service network restart

Now you should be able to access the Internet.

section index

Related Resources:

Mandrake Linux 8.1 - Errata
MF: Printing In 8.1 (I)
MF: X In 8.1
MF: devfs In 8.1
MF: Installation Desktop 8.1
MF: Installation Laptop 8.1
MF: Sound In 8.1
MF: ISA ~PnP Cards In 8.1
MF: Printing In 8.1 (II)

Revision / Modified: Feb. 02, 2002
Author: Tom Berger

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