You need to install ImageMagick if it is not already installed in the system:

# yum install ImageMagick

Convert image image.jpg from JPG to EPS format:

$ convert image.jpg image.eps

For other image formats, the command is similar.

Install ffmpeg

First, we should install the ffmpeg package. The Fedora Linux does not include ffmpeg in its repository for some reasons but the RPM Fusion repository provides it for us. To install the ffmpeg package, add RPM Fusion repository first.

The install the ffmpeg package:

# yum install ffmpeg

Convert video file format with ffmpeg

The basic command to convert video file input.wmv to onput.mp4 is as follows.

# ffmpeg -i input.wmv output.mp4

Or other format (such as .mov) by:

# ffmpeg -i input.wmv output.mov

ffmpeg determines the output video’s format by its file name extersion.

Convert video file format with ffmpeg for iPod/iPhone/iPad

The files in .mp4 format can be played on Apples devices. The iPod/iPhone/iPad have specific resolution, so we need to to convert the video files to a very high resolution since the devices can only display a limited one. We use the iPod generation 2 as the example, its screen resolution is 480×320. Hence, we can only convert the video to this resolution for smaller video file size. Similarly, the bitrate can also be set accordingly. The default one of ffmpeg (200 kb/s) is too low. To improve the quality of the converted video, we can set it to a larger one.

One good configuration for me is:

# ffmpeg -i input.wmv -s 480x320 -b 1000k output.mp4

-s sets the frame size of the video. -b sets the bitrate of the video.

Convert video file format with ffmpeg for iPod/iPhone/iPad in one command

More conveniently, we can form this command to a script convert2mp4.sh:

#!/bin/bash
ffmpeg -i $1 -s 480x320 -b 1000k /tmp/$1.mp4

Each time to convert a video file video.wmv, we can simply run:

$ convert2mp4.sh video.wmv

and the converted file is /tmp/video.wmv.mp4 after the script finishes.

This post makes a list of actions should be done to upgrade Fedora using yum. Please note that this is for experienced users only, if you are not sure what you are doing and what do these commands mean, please stop here and read the manuals first, or go to Fedora’s Wiki about upgrading Fediora using yum.

This post aims to be a general method, although we use Fedora 15 to Fedora 16 as the example. We configure and install grub2 as the bootloader.

Clean Stuff

It is a good time to remove packages we don’t use. These packages could be candidates for removal, but check to see whether you use them directly or if they are used by applications not backed by rpm packages.

# package-cleanup --leaves

You can find orphaned packages (i.e. packages not in the repositories anymore). This will also show packages which have been partially uninstalled but where the “%postun” script failed.

# package-cleanup --orphans

Do the upgrade

Go to a text console and run in level 3

ctrl + alt + F2

init 3

Update yum first

yum update yum

Clean all cached meta data and packages

yum clean all

Import the key for the newer version’s repository

For Fedora 16, it is

rpm --import https://fedoraproject.org/static/A82BA4B7.txt

Synchronizes the installed package set with the latest packages available

yum --releasever=<release_number_you_want_to_sync_to> distro-sync

For upgrading Fedora 15 to Fedora 16:

yum --releasever=16 --disableplugin=presto  distro-sync

Double check the updated repositories after distro-sync

yum repolist

Update groups

yum groupupdate Base

List all other groups

yum grouplist

and also update them

yum groupupdate ALL GROUPS LISTED

Use grub2 instead of grub

Make configuration for grub2

/sbin/grub2-mkconfig -o /boot/grub2/grub.cfg

Install grub2

/sbin/grub2-install BOOTDEVICE

For example, to install grub2 on sda:

/sbin/grub2-install /dev/sda

Reset services start/stop priorities

cd /etc/rc.d/init.d; for f in *; do /sbin/chkconfig $f resetpriorities; done

Reboot the system now

After reboot, you may see new kernel version on new Fedora version. For example, kernel 3.1.1 on Fedora 16

[root@localhost ~]# uname -a
Linux localhost.localdomain 3.1.1-1.fc16.x86_64 #1 SMP Fri Nov 11 21:47:56 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux

RPM Fusion

“RPM Fusion provides software that the Fedora Project or Red Hat doesn’t want to ship. That software is provided as precompiled RPMs for all current Fedora versions and Red Hat Enterprise Linux 5 and 6; you can use the RPM Fusion repositories with tools like yum and PackageKit.”

RPM Fusion has two separate software repositories. The free for Open Source Software (as defined by the Fedora Licensing Guidelines) which the Fedora project cannot ship due to other reasons. The nonfree for redistributable software that is not Open Source Software (as defined by the Fedora Licensing Guidelines); this includes software with publicly available source-code that has “no commercial use”-like restrictions.

To enable access to both the free and the nonfree repository use the following command.

Released and currently supported Fedora versions:

# yum localinstall --nogpgcheck http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm
# yum localinstall --nogpgcheck http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm

Fedora Rawhide and what will become the next Fedora version (Alpha, Beta and snapshots):

# yum localinstall --nogpgcheck http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-rawhide.noarch.rpm
# yum localinstall --nogpgcheck http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-rawhide.noarch.rpm

VMware Player

Install VMware Player

Download the installation bundle from VMware’s website. For example, the file we download is: VMware-Player-4.0.0-471780.x86_64.bundle .

Install needed kernel header and devel packages

# yum install kernel-headers kernel-devel

Run the bundle file

# sh VMware-Player-4.0.0-471780.x86_64.bundle

Then just follow the instruction of the GUI of the VMware installer, and you can finish the installation.

For Fedora 16 with kernel 3.1.0 or 3.1.1 with VMware Player 4.0.0, the vmnet module can not compile vmnet module. The VMware-Player-4.0.1-528992.x86_64 fixes this problem and works well with 3.1 kernel. If you want to run VMware Player 4.0.0, the community give patches to it so that it works with kernel 3.1. The patch and script given by Stefano Angeleri works well for me. You may use it quickly by the following commands.

$ wget http://weltall.heliohost.org/wordpress/wp-content/uploads/2011/09/vmware8linux31fix.tar.gz
$ tar xf vmware8linux31fix.tar.gz
# sh ./patch-modules_3.1.0.sh

systemctl prints a “[FAILED]” message. But you can ignore it and VMware Player works.

Run VMware Player

Just execute

$ vmplayer

Start a virtual machine just by one command

$ vmplayer /path/to/virtual/machine/config.vmx &

Give the path to the virtual machine configuration file (a .vmx file under the virtual machine’s directory) to vmplayer as its parameter.

Uninstall VMware Player

VMware installer provides the method to uninstall VMware products. We can use this tool

# vmware-installer  --uninstall-product vmware-player

It has a GUI and just follow its instruction to finish the uninstallation.

VirtualBox

Install VirtualBox

We use VirtualBox’s repository for Fedora here. We use VirtualBox-4.1 as the example.

Download the repository file.

# cd /etc/yum.repos.d
# wget http://download.virtualbox.org/virtualbox/rpm/fedora/virtualbox.repo

Install VirtualBox using yum

# yum install VirtualBox-4.1

Run VirtualBox

Just execute

$ virtualbox

Start a virtual machine just by one command

# VBoxManage startvm name_of_the_virtual_machine

VBoxManager use the virtual machine’s name as its parameter. The name can be found from VirtualBox’s virtual machine list.

Uninstall VirtualBox

As installing VirtualBox, we can uninstall (erase) it using yum

# yum erase VirtualBox-4.1

Install ns-2.34 on Fedora

Download the allinone package

$ wget http://downloads.sourceforge.net/project/nsnam/allinone/ns-allinone-2.34/ns-allinone-2.34.tar.gz

Uncompress the pacakge

$ tar xf ns-allinone-2.34.tar.gz

Install needed pacakges

# yum install gcc make libX11-devel libXt-devel libXmu-devel

Ns-2 requires older version of gcc. So we install gcc-34 and gcc-34-c++ for it

# yum install compat-gcc-34 compat-gcc-34-c++

Install the allinon package of ns-2. During the install process, specify the CXX compiler we use

$ cd ns-allinone-2.34
$ CXX=g++34 ./install

Configure the environmental variables for ns-2 and nam, and add the executables to the PATH so that we can use ns and nam directly.

Add to ~/.bashrc if you use bash

NS_HOME=/full/path/to/ns-allinone-2.34
PATH=$NS_HOME/bin:$NS_HOME/tcl8.4.18/unix:$NS_HOME/tk8.4.18/unix:$PATH
export PATH

or

Add to ~/.cshrc_user if you use c shell

setenv NS_HOME "/full/path/to/ns-allinone-2.34"
setenv PATH "${PATH}:${NS_HOME}/bin:${NS_HOME}/tcl8.4.18/unix:${NS_HOME}/tk8.4.18/unix"
setenv LD_LIBRARY_PATH "${NS_HOME}/otcl-1.13:${NS_HOME}/ns-2.34/lib:/usr/local/lib"
setenv TCL_LIBRARY "${NS_HOME}/tcl8.4.18/library"

The installation is done by this step. Open another shell and try our installation:

$ nam

and

$ ns

Install ns-3.12.1 on Fedora

Install needed packages

# yum install libxml2 libxml2-devel gcc gcc-c++ make automake \
autoconf binutils openssh-server openssh-clients openssl python \
python-devel mercurial bzr scons flex bison tcpdump valgrind gdb

Download the allinone pacakge for ns-3

$ mkdir tarballs
$ cd tarballs
$ wget http://www.nsnam.org/release/ns-allinone-3.12.1.tar.bz2
$ tar xjf ns-allinone-3.12.1.tar.bz2

Build ns-3

$ cd ns-allinone-3.12.1/
$ ./build.py

We will now interact directly with Waf in the ns-3.12.1 directory

$ cd ns-3.12.1

Configuration with Waf

$ ./waf -d optimized configure --enable-examples; ./waf

Validate our installation by running one example

$ ./waf shell
$ cd build/optimized/examples/
$ udp/udp-echo

Use tcpdump to display the simulation result

$ tcpdump -tt -r udp-echo-0-1.pcap

Install 32-bit firefox

First, install firfox.i686 package.

# linux32
# yum install firefox.i686

Firefox can simply run now. But we still need to fix some issues.

When run firefox, we may get these warnings:

(firefox:4860): Gtk-WARNING **: Unable to locate theme engine in module_path: “clearlooks”,
Gtk-Message: Failed to load module “pk-gtk-module”: libpk-gtk-module.so: cannot open shared object file: No such file or directory
Gtk-Message: Failed to load module “canberra-gtk-module”: libcanberra-gtk-module.so: cannot open shared object file: No such file or directory

To fix these warnings, install needed packages:

# yum install libcanberra-gtk2.i686 \
 gtk2-engines.i686 \
 PackageKit-gtk-module.i686

However, there is no input method. To enable ibus-gtk2 input method in 32bit Firefox, install the ibus-gtk2 package

# yum install ibus-gtk2.i686

Install the flash-plugin

Enable rpmfusion repository: Enable RPM Fusion repositories

Install flash plugin

# yum install flash-plugin.i386

Set up flash plugin

# /usr/lib/flash-plugin/setup

There is no sound in flash. For sound support and curl support, install

# yum install alsa-plugins-pulseaudio.i686 curl.i686

You should have sound. flash-plugin works.

Firefox should complain nothing and work well now. Enjoy it.

Additional gift:

Force to run firefox in 32-bit mode:

#!/bin/bash

setarch i686 firefox -new-tab $*

Set up a NFS Server

Configure /etc/exports to give clients the permission to use the NFS directories.

Edit /etc/exports

For example, to allow the servers inside subnet 10.0.0.1/24 to mount the /home directory with read/write permission. Add this line to /etc/exports:

/home 10.0.0.1/24(rw)

For details of the exports functions, please refer to export manual.

Start up the NFS service

Enable nfs service on the NFS server so that the NFS service daemon automatically starts each time the server starts:

# /sbin/chkconfig nfs on

You may also manually start it

# service nfs start

Client-slide configuration

Package installation

# yum nfs-utils

Start the rpcbind service

# service rpcbind restart

You may also set it to start automatically

# chkconfig rpcbind on

Mount the NFS directory

# mount NFS_SERVER:/lhome/userdir MOUNT_POINT

where NFS_SERVER is the NFS server’s address, and MOUNT_POINT is the local mount point on the client side for the NFS directory.

You may also consider using autofs on top of NFS as described in Unified Linux Login and Home Directory Using OpenLDAP and NFS/automount.

In this post, we introduce how to set up keys for git, how to configure non-standard SSH port for git, and how to use the first git repository.

Users’ SSH private/public key pairs

Every user of git, administrator or a normal user, need to have a private/public SSH key pairs in ~/.ssh.

New users need to generate the key pairs (if they don’t have one) by executing this command:

$ ssh-keygen -t rsa

After generating the key pairs, the user can give the public key (~/.ssh/id_rsa.pub) to the git server administrator and ask he/she to create a account and repository.

After the git server administrator adds the new user by its public key to the git server, the user can starts to use git.

Non-standard SSH port

This section only for the git servers that use non-stardard SSH port, i.e. other than 22.

If sshd is listening on non-standard port(s) on the git server, for example 22111, the user should set SSH to use the special port. We use example.org:22111 as the example here.

Put these two lines in your ~/.ssh/config file:

Host example.org
  Port 22111

If this ~/.ssh/config file doesn’t exist, you should create it first and set it’s mod to 744:

$ chmod 744 ~/.ssh/config

Create the new repository

This section only for users to create new repository. If the user is to use an already exist repository, please skip this section. Besides, the steps in this section only need to be done once for one repository.

We use the example that the administrator create repository repo1 for user1 and give user1 write privilege to this repository. We assume the address for this repository is git@example.org:repo1.git . Now we introduce how does user1 create the new repository repo1.

As user1 has the write privilege on the repo1 repository, it can create this repository on it’s local machine first and then push it to the git server. After pushing it to the git server.

These operations are done by user1 on its local machine:

$ mkdir repo1
$ cd repo1
$ git init
$ touch README
$ git add README
$ git commit -a -m 'first commit'
$ git remote add origin git@example.org:repo1.git
$ git push origin master

If it successes, the new repository is created on the git server.

Use the repository

Please note that step 1 only need to be done for the first time. After getting the repository to a local directory on the user’s local machine, the user only need to follow step 2 to step 5.

1. Clone the repository for the first-time. You only need to do it once for the first time, for the later usage of this repository, you continue use this local directory.

$ git clone git@example.org:repo1.git

A directory named repo1 will be created in the current directory.

If you want to use the repository directory in the previous section, just add these line to the end of .git/config:

[branch "master"]
remote = origin
merge = refs/heads/master

2. Pull the updates made before by you or the others. Use “git pull” command in the repository’s directory.

$ cd repo1
$ git pull

Then you can work on this updated copy of the repository by editing the files.

If you add a file or directory (for example, add directory a/b and file a/t.txt), you can add it to the repository by:

$ git add a/b a/t.txt

3. Commit the changes made by you with a message

$ git commit -a -m 'update the files'

4. Push it to the git server

$ git push

By now, your changes have been pushed to the git server. When the others use “git pull” command, they will get the new version of the source codes that have changed by you.

You can use “git log” to see the logs of all the commits of this repository.

You may be also interested in more git solutions.

64-bit flash plugin for Firefox on Linux

First, download Flash Player Release for 64-bit Linux from Adobe Labs.

Then, unpack the package:

$ tar xf flashplayer.tar.gz

Check whether all needed library is ready for it. If not, install the needed packages.

$ ldd libflashplayer.so

Give it executable attribute:

$ chmod +x libflashplayer.so

Copy the plugin to the plugin directory so that Firefox can use it:

$ cp libflashplayer.so ~/.mozilla/plugins/

32-bit flash plugin for Firefox on Linux

32-bit flash plugin can also work well for 64-bit firefox on 64-bit Linux. We can use the rpm packages from adobe’s repository.

First, install adobe release repository:

# rpm -Uvh http://linuxdownload.adobe.com/adobe-release/adobe-release-i386-1.0-1.noarch.rpm

Install nspluginwrapper so that 32-bit plugins can run on 64-bit system, and 32-bit alsa plugin for pulseaudio so that the 32-bit flash plugin can play sound on the 64-bit system.

# yum install nspluginwrapper.{x86_64,i686} \
 alsa-plugins-pulseaudio.i686 --disablerepo=adobe-linux-i386

Install the 32-bit flash plugin:

# su -c 'yum install flash-plugin'