My Linux Life

Perl: Terminal does not support AddHistory

2012-01-24T23:53:00.001+08:00

If you see the error when running Perl shell, you need to install Term::ReadLine::Perl.

That's all there is to it. Have fun!.

changing manually wireless connection to be controlled by knetworkmanager

2012-01-24T23:03:00.000+08:00

knetworkmanager is a Network Manager for KDE4. It is hated or liked by users and usually not in between. I personally like it although it has its fair share of bugs. But I like Mandriva's net_applet more. It is stable and more reliable. It is prefered by many Mandriva users. However, if you are stuck with recent problems (bug?) of perl in Mandriva Cooker like me, you are forced to use command line of wpa_supplicant or iwconfig or using gui application like knetworkmanager.

In Mandriva, you can change which network manager control the wireless connection by changing the option in net_applet or you can manually change in file /etc/sysconfig/network-scripts/ifcfg-wlan0. If you want knetworkmanager in control of it, you just have to change this line to yes:

NM_CONTROLLED=yes

Connecting to wireless AP with WPA/2 security using wpa_supplicant

2012-01-22T18:22:00.000+08:00

Recently, my cooker updated perl packages and it broke all of drak* family especially drakconf and net_applet. net_applet is the network manager for Mandriva in applet form. I can also use draknetcenter. Now the problem is I cant open net_applet and knetcenter due to this error:

/usr/bin/perl: symbol lookup error: /usr/lib/libDrakX/auto/c/stuff/stuff.so: undefined symbol: Perl_Gthr_key_ptr

So how do I connect to wireless AP? I dont know how to use iwconfig to connect to such AP or can I? After googling, I found a solution: wpa_supplicant. In Mandriva, I just have to run this command (as root):

wpa_supplicant -Dwext -iwlan0 -c/etc/wpa_supplicant.conf &

If you have setup the connection before with draknetcenter, you dont have to edit the file wpa_supplicant.conf. If not, you have to manually edit the file to suit your environment. it is heavily documented.

Then you have to run dhclient to get IP address from the AP or other dhcp server:

dhclient wlan0

wlan0 is my wireless interface. Please change it according to your environment. I bet the broken packages will be updated sooner so that I can use net_applet again.

Have fun!

Happy New Year and distros for router

2012-01-02T05:14:00.000+08:00

Happy New Year everbody. Hope 2012 will be a great year for Linux. In 2011, I tested several distros for different purposes. For routers, I found several free distros that serve as a really good gateway for my network. Among others are:

Zentyal - this is the best distro for routers. Fully featured with webcache, url filtering, load balancing for multiple lines and has 32-bit and 64-bit version. It is based on Ubuntu.
ClearOS - Also the best but it doesn't have 64-bit version (at the time of this writing. recently there's a 64-bit release but still in beta stage). Has many features as Zentyal. Based on Redhat.
pfSense - this is not Linux-based. It is freeBSD-based firewall and router. It has bug with my servers pertaining to PCI-E. So I dumped it. It's good but the bug prevent it from being operational.

Others:

Untangle - didn't try it because the free version has no webcache feature.
Zeroshell - tried it but a little awkward to use.

So I chose Zentyal as my distro for my server router and info from its web, I need to add more RAM and bigger hard disk to serve more than 500 users.

Happy New Year everybody! Thanks for reading.

Changing konqueror web browser's engine to WebKit

2011-10-17T11:06:00.000+08:00

Konqueror is a native KDE web browser and it uses KHTML as the rendering engine. Fortunately, the smart developers of Konqueror has made it possible to change not only the interface but also the engine that renders the webpage we visit and so far only webkit is supported. We hope many more in the future. or maybe not. :)

What is Webkit?

Webkit engine is derived from KDE's KHTML engine and contains many enhancements that made it better than its mother. It has been used for Apple's Safari and Google's Chrome web browsers.

For Mandriva 2011 users, to be able to change the engine to Webkit is by installing the engine package. It's called webkitkde. (for other distro, the package name might be a bit different) You might have installed it. Install it using this command:

urpmi webkitkde

Now open Konqueror (or restart if it is open) and go to Settings --> Configure Konqueror --> General --> Default web browser engine. You should have 2 options in there. KHTML and WebKit. Screenshot below.

That's all there is to it. You should now enjoy browsing the web using WebKit engine.

Mandriva 2011 codenamed Hydrogen is out

2011-08-30T21:14:00.002+08:00

I just copy this as announced on Mandriva blog:

Hooray! As promised earlier, we are happy to announce that Mandriva 2011 is out. You can download ISO images from here.

When downloading an iso-image, perhaps you will want to read the Release Notes.

We prepared a small manual of how to upgrade to the new release for users of the Mandriva Desktop 2010.2.

If you have never tried Mandriva, take a look at the Mandriva 2011 Tour.

Happy upgrading :)

Merging video files

2011-08-22T01:30:00.002+08:00

Recently I downloaded 2 video files which is actually a video file splitted into two for faster upload by the uploader. To merge them on Linux, we can use the command cat like this:

cat video1.mkv video2.mkv >> video.mkv

And it took seconds to complete merging. Now I can watch the video in 1 file.

Have fun!.

Testing bloggeroid

2011-06-19T16:06:00.001+08:00

This post is for testing purposes only. Please <<ignore>> it.

posted with Bloggeroid

Mageia 1 is out!

2011-06-04T00:35:00.003+08:00

A distribution forked from Mandriva, Mageia, released its important milestone, Mageia 1 stable. Read the Changelog here to get an insight of this release after 9 months it was born.

My Mandriva desktop

2011-05-26T01:06:00.009+08:00

Sorry for not posting anything for a rather long time. I have been using Mandriva Cooker 2011 for about 2 months now since I bought my new ASUS laptop from someone with half the current market price. :) With RPM5, ROSA, and many exciting features of KDE 4 in Cooker, I didn't want to miss the chance to test and have fun with them.

Here is the screenshots of my desktop with urpmi and 3D effects in action.

Please click on the image to see bigger picture.

Load balance 2 WAN links BASH script

2011-04-08T02:02:00.002+08:00

BASH script to load balance 2 WAN links.

#!/bin/bash

# bal_local Load-balance internet connection over two local links

# Version: 1.0.0 - Fri, Sep 26, 2008

# Author: Niels Horn

# Set devices:

DEV1=${1-eth0} # default eth0

DEV2=${2-ppp0} # default ppp0

# Get IP addresses of our devices:

ip1=`ifconfig $DEV1 | grep inet | awk '{ print $2 }' | awk -F: '{ print $2 }'`

ip2=`ifconfig $DEV2 | grep inet | awk '{ print $2 }' | awk -F: '{ print $2 }'`

# Get default gateway for our devices:

gw1=`route -n | grep $DEV1 | grep '^0.0.0.0' | awk '{ print $2 }'`

gw2=`route -n | grep $DEV2 | grep '^0.0.0.0' | awk '{ print $2 }'`

echo "$DEV1: IP=$ip1 GW=$gw1"

echo "$DEV2: IP=$ip2 GW=$gw2"

### Definition of routes ###

# Check if tables exists, if not -> create them:

if [ -z "`cat /etc/iproute2/rt_tables | grep '^251'`" ] ; then

echo "251 rt_dev1" >> /etc/iproute2/rt_tables

if [ -z "`cat /etc/iproute2/rt_tables | grep '^252'`" ] ; then

echo "252 rt_dev2" >> /etc/iproute2/rt_tables

# Define routing tables:

ip route add default via $gw1 table rt_dev1

ip route add default via $gw2 table rt_dev2

# Create rules:

ip rule add from $ip1 table rt_dev1

ip rule add from $ip2 table rt_dev2

# If we already have a 'nexthop' route, delete it:

if [ ! -z "`ip route show table main | grep 'nexthop'`" ] ; then

ip route del default scope global

# Balance links based on routes:

ip route add default scope global nexthop via $gw1 dev $DEV1 weight 1 nexthop via $gw2 dev $DEV2 weight 1

# Flush cache table:

ip route flush cache

# All done...

To use the script, copy it to /usr/local/bin, make it executable with 'chmod +x' and call it with:

bal_local

source

Moving your mysql database to another hard disk

2011-01-31T23:36:00.004+08:00

Recently, my server's only hard disk was almost full. I bought a new hard disk with bigger size and I decided to just add it as a second hard disk. Since I need to move it to the 2nd hard disk, I need to find a proper way to move the db with minimum downtime. So I googled around and found a solution.

First, I needed to format the 2nd hard disk and I chose xfs as the filesystem. I created 2 partitions using Linux's fdisk for this task. First partition is 10 GB and 2nd one is around 900 GB. That's approximately added up to 1 TB. Then I mounted the 2nd partition in current partition eg /media/hd2 as follows:

mount -t xfs /dev/sdb5 /media/hd2

where /dev/sdb5 is the partition and /media/hd2 is the mounting dir.

Stop mysql db before doing anything:

service mysql stop

Afterthat, I copied the entire db to newly mounted hard disk:

cp -rv /var/lib/mysql /media/hd2

It will take a while if you have huge databases.

Then, change the ownership of the dir to user and group of mysql:

chown -R mysql:mysql /media/hd2/mysql

You need to change the mysql config file in /etc/my.cnf to point to the dir:

[mysqld]

user = mysql

datadir = /media/hd2/mysql

port = 3306

socket = /var/lib/mysql/mysql.sock

pid-file = /var/run/mysqld/mysqld.pid

Now you can restart mysql db:

service mysql start

If there are no errors on startup, you can test by login to your mysql db and do sql query.

You can leave other settings as it is. If this doesn't work and if you use innodb, you may want to change these lines:

# Uncomment the following if you are using InnoDB tables

#innodb_data_home_dir = /var/lib/mysql/

#innodb_data_file_path = ibdata1:10M:autoextend

#innodb_log_group_home_dir = /var/lib/mysql/

#innodb_log_arch_dir = /var/lib/mysql/

Make sure you test your dbs before deleting the old ones. Have fun!

The easiest way to 'burn' iso to USB disk.

2011-01-18T23:28:00.002+08:00

The easiest way to 'burn' iso to USB disk is by using dd command. Let's say you don't want to burn your newly downloaded iso to CD/DVD but want to use USB disk instead, you can run this command :

dd if=/path/to/file.iso of=/dev/sdb

This assumes your USB disk is /dev/sdb. You can use mount command to check what device your USB disk is using. Now you can install your new distro using USB disk.

Have fun!

/usr/include/linux/netfilter_ipv4.h:53: error: ‘INT_MIN’ was not declared in this scope

2011-01-04T11:00:00.008+08:00

This error happened when I was compiling dansguardian 2.10.1.1 with Linux netfilter support.

In file included from ConnectionHandler.cpp:48:

/usr/include/linux/netfilter_ipv4.h:53: error: ‘INT_MIN’ was not declared in this scope

/usr/include/linux/netfilter_ipv4.h:64: error: ‘INT_MAX’ was not declared in this scope

/usr/include/linux/netfilter_ipv4.h:65: error: ‘INT_MAX’ was not declared in this scope

make[2]: *** [dansguardian-ConnectionHandler.o] Error 1

To solve it, you have to edit netfilter_ipv4.h and type #include <limits.h> just below or after other #include lines.

Have fun!.

How to change the plymouth default theme

2011-01-04T00:21:00.004+08:00

Plymouth is a graphical boot system that runs very early in the boot process. It provides graphical animation while the boot process happens in the background. Starting from Mandriva 2010 Beta, it replaced splashy to manage boot splash. Many latest distributions now are using plymouth. Since it displays graphical boot login, users usually do not bother to tinker with it.

What is the default theme?

To know the current default theme, run this command without any options:

plymouth-set-default-theme

Changing theme

To change plymouth theme, we have to know what themes are installed. To list them, run (as root):

plymouth-set-default-theme --list

You'll get something like this:

details

fade-in

Mandriva-Free

spinfinity

text

So to change to a particular theme as the default, for example fade-in, run :

plymouth-set-default-theme fade-in --rebuild-initrd

--rebuilt-initrd option is a must or the change won't take effect. You can explore other options by running plymouth-set-default-theme -h

Have fun!

urpmi: /bin/mv: cannot stat `/var/cache/urpmi/partial/descriptions': No such file or directory

2010-12-30T23:35:00.003+08:00

If you got this problem (or something like it) while updating packages with urpmi.update -a or urpmi --auto-updates :

/bin/mv: cannot stat `/var/cache/urpmi/partial/descriptions': No such file or directory

Can't move file /var/cache/urpmi/partial/descriptions to /var/lib/urpmi/Main Updates (Cooker2011.0-2)/descriptions

Then the solution is by removing the file /var/cache/urpmi/mirrors.cache for urpmi to use different mirror. This is because the mirror has problem. So issuing this command should solve the problem:

rm -fv /var/cache/urpmi/mirrors.cache

That's all there is to it. Have fun!

Solving squid's pinger error: IcmpSquid.cc(155) Recv: recv: (111) Connection refused

2010-12-18T17:02:00.003+08:00

I've installed latest squid (3.2.0.3) recently from source. I configured it with --with-icmp to enable incoming icmp request. After compiling and installing it, it's time to run it. From the log I noticed that the pinger program produced an error like this:

IcmpSquid.cc(155) Recv: recv: (111) Connection refused

and filtering the log of the word pinger (using grep) :

pinger: Initialising ICMP pinger ...

2010/12/18 10:57:16| pinger: Unable to start ICMP pinger.

2010/12/18 10:57:16| pinger: Unable to start ICMPv6 pinger.

2010/12/18 10:57:16| FATAL: pinger: Unable to open any ICMP sockets.

From the errors above, I knew that they were related to permission problem (connection refused, unable to open socket). It solved when I setuid the pinger program to enable it to open the required socket :

chown 4755 pinger (run this as root of course)

This pinger program is usually located in the bin directory of squid path e.g /usr/local/squid/bin (this is the default if you compile from source). Please consult your distro if you install it using package manager.

After restarting squid, I could see in the log as below:

pinger: Initialising ICMP pinger ...

2010/12/18 16:58:48| pinger: ICMP socket opened.

2010/12/18 16:58:48| pinger: ICMPv6 socket opened

That I think solved the problem. Have fun.

What's coming in Mandriva 2011

2010-12-05T19:29:00.003+08:00

After the wonderful news that Mandriva would be continuing as usual despite financial difficulties and an exodus of developers comes the technical specifications and other tidbits for Mandriva 2011. There are quite a few exciting changes ahead, many of which prove that Mandriva is still a cutting edge distribution.

With 2011, Mandriva will be switching to RPM5. This news was announced by Per Øyvind Karlsen last week and is the first item in the list. RPM5 is actually a fork of RPM with the main goals of supporting XAR, an XML based archiving format, and featuring an integrated dependency resolver. This move has been in the works for quite some time but Mandriva 2011 will be the first release fully committed. Per Øyvind Karlsen said RPM5, "is the only sensible choice." Relatedly, their software center is scheduled a face-lift for a "more modern and simple to use interface."

Mandriva 2011 will be using the Galbraith Latency patch whether the kernel that will be used has it or not - meaning they will backport it if necessary. This latency patch, first brought to wide attention by Phoronix.com, is said to help speed up desktop processes especially in the areas of graphic and video rendering.

It is listed that Mandriva would be adopting systemd for the boot process. Several other distributions started out trying to move to systemd, but so far, they have changed their minds due to difficulties associated with such a major subsystem replacement. But Mandriva is going to give it the ole college try for 2011. The advantages of systemd are faster boots for some setups because of parallel, early background, and dependency booting of processes.

Like several other distributions have done, most of Mandriva's configuration tools will be integrated into the KDE Control Center (System Settings) in 2011.

All the logins and desktops are getting new a new look and improved resource consumption. No further details on any of these items are given at this time, but it's always exciting to see what the new releases will look like.

The installer is supposed to be simplified in order to be more new user-friendly. Desktop selection and installation summary steps will be removed, meaning those will personal preferences or cranky hardware will have to wait until after the install.

During this cycle, Cooker will no longer be frozen before release and instead continue to be developed in parallel. The release code will be branched off and Cooker will proceed as a rolling release.

Finally, something originally asked for over three years ago is finally being implemented. A new user Welcome application will be added in order to help new and migrating users to acclimate to Mandriva. Again, no further details what will exactly be included, but one can speculate it will give links to online resources such as forums and documentation; perhaps a tour of the desktop, menu, and applications; and maybe offer to install popular applications, codecs, and drivers.

And unfortunately, there are still no plans posted about a 64-bit One release. One has the advantage of being shipped with proprietary codecs and drivers that aren't available in the other versions, so a 64-bit version would be extremely handy.

Of course, there are lots of other highly technical deep code improvements ahead as well. But just looking at the items that users will notice easily, Mandriva 2011 certainly sounds very exciting. A release candidate is scheduled for April 25 and final is planned for May 30.

Source

Firefox 4 Beta and Greasemonkey Add-on

2010-10-29T17:35:00.002+08:00

If you are using Firefox 4 Beta (i'm using Beta 6) and want to install Greasemonkey add-on through Tools --> Add-ons, you're out of luck. But there's a website that provides nightly build Greasemonkey:

https://arantius.com/misc/gm-nightly/

Click Allow if prompted before installing. This add-on is for testing purposes and may not stable. Please remember that you're also using Firefox Beta.

Have fun!

A preview of next flash player released

2010-09-16T12:24:00.004+08:00

A preview release of the next Flash Player released. Codenamed as Square, designated as version 10.2.161.22) and available for download right from Adobe Labs. It is not only available in 32-bit but also in 64-bit for Mac, Windows and Linux operating systems. For the 64-bit release,this is the first time preview for Mac and Windows OS users.

This release has an advantage for IE9 Beta users where it has been enhanced to directly support the hardware-accelerated graphics capabilities in the newest version of IE. Flash Player "Square" leverages the new GPU support available with IE 9 Beta to deliver a faster and more responsive user experience (more than 35% improved performance).

Users are encouraged to test this release especially for the 64-bit. If you encounter any issues, please file a bug report here: https://bugs.adobe.com/flashplayer/

KDE 4.5 stable released

2010-08-11T19:53:00.003+08:00

KDE 4.5 stable released. For Mandriva users, please add KDE 4.5 repo (as root):

64-bit:

urpmaddmedia kde-4.5 http://ftp.twaren.net/Unix/X/KDE/stable/4.5.0/Mandriva/2010.1/x86_64/

32-bit:

urpmi.addmedia kde-4.5 http://ftp.twaren.net/Unix/X/KDE/stable/4.5.0/Mandriva/2010.1/i586/

You may want to remove the old KDE repo first.

or if you prefer KDE server as your repo thusly:

64-bit:

urpmi.addmedia kde-4.5 ftp://ftp.kde.org/pub/kde/stable/4.5.0/Mandriva/2010.1/x86_64

32-bit:

urpmi.addmedia kde-4.5 ftp://ftp.kde.org/pub/kde/stable/4.5.0/Mandriva/2010.1/i586

Have fun!

KDE 4.5 RC3 released for Mandriva

2010-08-02T02:27:00.003+08:00

KDE 4.5 Release Candidate 3 is released for Mandriva users. The final version will be available next week. This last RC is intended for verifying no showstoppers will creep into the final release of 4.5.0. It will also interest those who want an early look at what is coming to their desktops and netbooks this summer.

To install, please add KDE 4.5RC3 repo first:

urpmi.addmedia kde-4.5rc3 http://ftp.twaren.net/Unix/X/KDE/unstable/4.4.95/Mandriva/2010.1/x86_64/

I use above mirror for my repo for faster access. You may want to use main KDE server for your repo thus:

urpmi.addmedia kde-4.5rc3 ftp://ftp.kde.org/pub/kde/unstable/4.4.95/Mandriva/2010.1/x86_64/

For x86 (32-bit) users, please change the path x86_64 to i586. Then run urpmi --auto-select to update your KDE packages.

Have fun with your new KDE!

Mandriva Linux Spring 2010 released

2010-07-09T16:10:00.006+08:00

Mandriva Linux 2010.1 aka Mandriva Linux Spring 2010 code named Farman released. For more information please check out Mandriva's Blog and website especially the new features in this release. You can download it here. Please also read the errata page for know bugs and other issues.

Have fun with this latest Mandriva offering.

Batch resize your images using mogrify

2010-06-24T14:04:00.003+08:00

Let's say you have lots of images and want to upload them to Facebook or to your website but you have to resize or edit all the images to suitable size for faster web access without losing too much of the quality of them. One tool to help you in this situation is mogrify.

mogrify is in imagemagick package. So you just need to install the package to get it. How to use it? Let's see some examples below:

1. mogrify -resize 320x240 *.jpg

This command will resize all files ending with .jpg (jpeg image) to resolution of 320x240 and replace all the files with the same name. mogrify may not produce the exact resolution to preserve aspect ratio.

2.mogrify -path Image-Small/ -resize 800x600 -density 25x25 *.gif

This command will resize all images ending with .gif to 800x600 with density 25x25. The resized images will be saved in Image-Small directory. So the original files is unmodified.

3. mogrify -resize 50% rose.jpg
This will resize the image to 50% and the original file replaced.

4. mogrify -format jpg *.png
This will convert all png files in currect directory to jpeg.

mogrify has many options for you to explore. Just man mogrify to read the manual or go to http://www.imagemagick.org/www/mogrify.html. For more command-line examples, go here.

Mandriva 2010 Spring RC released

2010-05-21T22:24:00.002+08:00

The Mandriva developers have announced the arrival of a release candidate (RC) for Mandriva Linux 2010 Spring (2010.1). This is to be the last development release for Mandriva Linux 2010 Spring and the final version is scheduled for release on the 3rd of June, 2010.

Building on the previous beta releases, the RC is based on the 2.6.33.4 Linux kernel and features the latest GNOME 2.30.1 and KDE 4.4.3 desktops. A number of changes have been implemented in the Nautilus file manager in anticipation of the GNOME 3.0 release with the GNOME Shell. Built-in desktop applications include version 3.2 of OpenOffice.org, Firefox 3.6.3, the Chromium web browser and version 1.92 of the Transmission BitTorrent client. Other changes include use of the Nouveau driver for NVIDIA graphics hardware and improvements to the Mandriva tools, such as data encryption, parental control and network profiles.

As with all development releases, use in production environments and on mission critical systems is not advised. Users testing the release are encouraged to provide feedback and report any bugs that they encounter. It's not for the faint of heart.

More info can be read here: http://wiki.mandriva.com/en/2010.1_RC