Wednesday, 24 February 2016

Boost on Ubuntu

This post describes how to install the boost library on Ubuntu.

Install the available package

If it doesn't need to be the latest version of boost, just install the version Ubuntu provides.
sudo apt-get install libboost-all-dev

Install latest version

If you want a more current version of boost than provided by Ubuntu, download and install it manually like showed here. At first download the version you want. I downloaded version 1.60 and also tried with version 1.57, you can chose whichever you want.

wget -O boost_1_60_0.tar.gz http://sourceforge.net/projects/boost/files/boost/1.60.0/boost_1_60_0.tar.gz/download
tar xzvf boost_1_60_0.tar.gz
cd boost_1_60_0/

Install all dependencies required to run boost without problems

sudo apt-get install build-essential g++ python-dev autotools-dev libicu-dev build-essential libbz2-dev libboost-all-dev

Prepare the installation with bootstrap. You can define the location it will be installed later with the prefix argument.

./bootstrap.sh --prefix=/usr/local
Then in the final step install boost with b2.
sudo ./b2 install

Sunday, 15 November 2015

Python on Cloud Foundry

Cloud Foundry is an open source cloud application platform. It can be installed on an own Server or bought as a service from a company. I myself tried cloud foundry provided by Swisscom. The advantage of the service is on one hand the integrated third party tools like database connections.

This post just describes how to get your python application running on already installed cloud foundry platform, not the installation of the platform. The demo application is a basic cloud interface based on the falcon framework for cloud API.

Preparations

To generate the dependencies for your cloud environment you need pip and virtualenv, which can be installed like this.

sudo apt-get install python-pip, python-virtualenv

Since the demo application uses a falcon cloud API we need falcon. Cython is used to improved the falcon's performance and gunicorn is the http server to run the falcon application on.

sudo pip install cython, falcon, gunicorn

Setup for the project

The whole project for the cloud has to be saved in one folder. To make the installation of the application on the cloud easier are we providing a requirements.txt file and a manifest.yml. Besides this is the folder containing the source for the application, in our case the file server.py.

The manifest.yml has to be written manually. It contains the information about the application. A very simple manifest can you see here.

---
applications:
- name: Example
  memory: 256M
  command: "gunicorn server:app"

The requirements.txt file can be generated automatically using virtualenv. For this open terminal, and create a new virtual environment for our cloud application. Within this virtual environment we install all the required packets to run our application, which is in our case again cython, falcon and gunicorn. With the pip freeze command its possible to print the currently installed packets into the requirements file.

virtualenv env
source env
pip install --upgrade cython falcon gunicorn
pip freeze > example/requirements.txt
deactivate
rm -r env

Upload the application to the cloud

To be able to upload your project to the cloud you need to install the command line interface to the cloud. You can download the one for your system here. Go to the folder containing your application and log into your cloud with the following command and enter your password.

cf login -a https://your-cloud.com -u myusername

Within the cloud you have to change to the space which will contain your app later. For this switch to it with the following command.

cf target -o myusername -s DEVSPACE

Now you can push your application to the cloud using the cf push command. You don't need to specify any more parameters in the push command since we already defined them all in the manifest.yml.

cf push
That's already it. For everyone wanting a starting point for their falcon application is here a simple hello world application for the falcon.
import falcon

class HelloWorld(object):
    def on_get(self, req, resp):
        resp.body = "hello world"
        resp.status = falcon.HTTP_200

app = falcon.API()
helloWorld = HelloWorld()
app.add_route('/helloworld', helloworld)
More support for your first falcon project is available on the official tutorial.

Sources

Monday, 21 September 2015

OpenCV with CUDA on Ubuntu 14.04

This post describes how to install OpenCV with CUDA support on a PC with Ubuntu 14.04. To install OpenCV with CUDA support, CUDA needs to be installed in a first step. If you already have a CUDA installation you can jump to the OpenCV installation.

The installation was tested on Ubuntu 14.04 LTS with CUDA 7.5 and OpenCV 3.0

First Step: Installation of CUDA

The current CUDA version is 7.5. It can be downloaded from the Nvidia developers page (CUDA-Toolkit).

Installation of the CUDA Toolkit

sudo dpkg -i cuda-repo-ubuntu1404_7.5-18_amd64.deb
sudo apt-get update
sudo apt-get install cuda

Environmental Variables

The CUDA toolkit needs to be added to the path and library path so it can be used by other applications. This can be done in the .bashrc file or in the /etc/environment file. In our case it is defined in the /etc/environment file.

PATH="...:/usr/local/cuda/bin"
LD_LIBRARY_PATH="/usr/local/cuda/lib64"

Test Installation

To load the new environmental variables restart the PC. Afterwards it should be possible to generate the provided samples with the command

cuda-install-samples-7.5.sh .
With the example deviceQuery it is possible to verify the CUDA installation, which is run as followed.
cd NVIDIA-CUDA-7.5_Samples/1_Utilities/deviceQuery
make
./deviceQuery

This should return an output similar to the following.

./deviceQuery Starting...

 CUDA Device Query (Runtime API) version (CUDART static linking)

Detected 1 CUDA Capable device(s)

Device 0: "Quadro K2200"
  CUDA Driver Version / Runtime Version          7.5 / 7.5
  CUDA Capability Major/Minor version number:    5.0
  Total amount of global memory:                 4095 MBytes (4294246400 bytes)
  ( 5) Multiprocessors, (128) CUDA Cores/MP:     640 CUDA Cores
  GPU Max Clock rate:                            1124 MHz (1.12 GHz)
  Memory Clock rate:                             2505 Mhz
  Memory Bus Width:                              128-bit
  L2 Cache Size:                                 2097152 bytes
  Maximum Texture Dimension Size (x,y,z)         1D=(65536), 2D=(65536, 65536), 3D=(4096, 4096, 4096)
  Maximum Layered 1D Texture Size, (num) layers  1D=(16384), 2048 layers
  Maximum Layered 2D Texture Size, (num) layers  2D=(16384, 16384), 2048 layers
  Total amount of constant memory:               65536 bytes
  Total amount of shared memory per block:       49152 bytes
  Total number of registers available per block: 65536
  Warp size:                                     32
  Maximum number of threads per multiprocessor:  2048
  Maximum number of threads per block:           1024
  Max dimension size of a thread block (x,y,z): (1024, 1024, 64)
  Max dimension size of a grid size    (x,y,z): (2147483647, 65535, 65535)
  Maximum memory pitch:                          2147483647 bytes
  Texture alignment:                             512 bytes
  Concurrent copy and kernel execution:          Yes with 1 copy engine(s)
  Run time limit on kernels:                     Yes
  Integrated GPU sharing Host Memory:            No
  Support host page-locked memory mapping:       Yes
  Alignment requirement for Surfaces:            Yes
  Device has ECC support:                        Disabled
  Device supports Unified Addressing (UVA):      Yes
  Device PCI Domain ID / Bus ID / location ID:   0 / 3 / 0
  Compute Mode:
     < Default (multiple host threads can use ::cudaSetDevice() with device simultaneously) >

deviceQuery, CUDA Driver = CUDART, CUDA Driver Version = 7.5, CUDA Runtime Version = 7.5, NumDevs = 1, Device0 = Quadro K2200

Result = PASS

Second Step: Installation of OpenCV

Requirements OpenCV

sudo apt-get install libopencv-dev build-essential checkinstall cmake pkg-config yasm libtiff4-dev libjpeg-dev libjasper-dev libavcodec-dev libavformat-dev libswscale-dev libdc1394-22-dev libxine-dev libgstreamer0.10-dev libgstreamer-plugins-base0.10-dev libv4l-dev python-dev python-numpy libtbb-dev libqt4-dev libgtk2.0-dev libfaac-dev libmp3lame-dev libopencore-amrnb-dev libopencore-amrwb-dev libtheora-dev libvorbis-dev libxvidcore-dev x264 v4l-utils

Get OpenCV Repository

Clone the official OpenCV repository from github. It will create the folder opencv and copy the repository in it.

git clone https://github.com/Itseez/opencv.git
It will take a moment to download the repository.

Build OpenCV

cd opencv
mkdir release
cd release
cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D WITH_TBB=ON -D BUILD_NEW_PYTHON_SUPPORT=ON -D WITH_V4L=ON -D INSTALL_C_EXAMPLES=ON -D INSTALL_PYTHON_EXAMPLES=ON -D BUILD_EXAMPLES=ON -D WITH_QT=ON -D WITH_OPENGL=ON -D ENABLE_FAST_MATH=1 -D CUDA_FAST_MATH=1 -D WITH_CUBLAS=1 ..
Check the configuration summary in the end. Make sure that CUDA support is activated with the correct version and CUBLAS is activated as well.
--     Use Cuda:                    YES (ver 7.5) 
--     Use OpenCL:                  YES
--
--   NVIDIA CUDA
--     Use CUFFT:                   YES
--     Use CUBLAS:                  YES
--     USE NVCUVID:                 NO
--     NVIDIA GPU arch:             20 21 30 35
--     NVIDIA PTX archs:            30
--     Use fast math:               YES

Install OpenCV

If the configuration looks fine can the installation be started. The installation can take up to a few hours.
make
sudo make install

Configure the library search path

Create the file /etc/ld.so.conf.d/opencv.conf and add the following line.
/usr/local/lib
Add the following line to the ~/.bashrc file

PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig
Reload the bashrc file for the current session

source ~/.bashrc

Sources

Sunday, 26 April 2015

Ubuntu daemon

Creating a service on Ubuntu 14.04

Creating a daemon on Ubuntu is quite simple. To run your own daemon scripts on boot-up can be done in the following steps:

Create a daemon in /etc/init.d

The daemon to be run needs to be in the init.d folder. Ubuntu provides a template with the daemon /etc/init.d/skeleton. Therefore copy the skeleton script and name it however you like.

sudo cp /etc/init.d/skeleton /etc/init.d/mydaemon

To be able to run the daemon it it necessary to make it executable

sudo chmod +x /etc/init.d/mydaemon

Adapt the script mydaemon to match your functionality, in the example the executable is in your $HOME/bin directory. The lines to be adapted are highlighted.

#! /bin/sh
### BEGIN INIT INFO
# Provides:          mydaemon
# Required-Start:    $remote_fs $syslog
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Short-Description: My Daemon
# Description:       This file starts my daemon
### END INIT INFO

# Author: Foo Bar 
#
# Please remove the "Author" lines above and replace them
# with your own name if you copy and modify this script.

# Do NOT "set -e"

# PATH should only include /usr/* if it runs after the mountnfs.sh script
PATH=/sbin:/usr/sbin:/bin:/usr/bin:/home/user/bin
DESC="my daemon"
NAME=mydaemon
DAEMON= mydaemon
DAEMON_ARGS="--options"
PIDFILE=/var/run/$NAME.pid
SCRIPTNAME=/etc/init.d/$NAME

Afterwards try to start and stop your daemon with

sudo service mydaemon start
sudo service mydaemon stop

Start daemon at boot

To automatically start the daemon at boot time it is necessary to add it to the boot list. This is done with the following command:

update-rd.d mydaemon default 97 03

If you want to remove the daemon again use the following command:

update-rd.d -f mydaemon remove

Thursday, 16 October 2014

Wordpress on Ubuntu 14.04

Wordpress is a free to use tool to create easy and fast your own website or blog. This entry shows how to easily install it on your own PC to use it as a webserver.
The installation is done on an Ubuntu 14.04LTS system. The installation is split in 3 steps and can be done in a few minutes.

Installation of the Server

Apache 2 is the most common web server application and is widely supported. Together with PHP and MySQL it provides a full capable web server. To install it with all the needed packages can be done with the following command.
$ sudo apt-get install lamp-server^
Download the latest version of wordpress from its server or get it with
$ wget https://wordpress.org/latest.tar.gz
and unzip it and into the directory /var/www/html/
sudo tar -xvzf latest.tar.gz -C /var/www/html/

Allow Wordpress to use your MySQL Server

Set up your MySQL Server so wordpress can access its database. I'd recommend to create new user with its independent database for wordpress to keep it separated from any other projects you might be running.
The MySQL Server can be updated using its own shell.
$ mysql -u root -p
There you can manage your databases and users. To create a wordpress user with its database we need the following 4 commands.
CREATE DATABASE wordpress;
CREATE USER 'wordpressUser'@'localhost' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON wordpress . * TO 'wordpressUser'@'localhost';
FLUSH PRIVILEGES;
Quit the MySQL Shell with the command
quit

Install Wordpress

We are now ready to run the installation of wordpress. For this call your website in the browser at localhost/wordpress. Follow the instructions to complete the installation.
It might be possible that installation is not able to load the content when you try to access the web site from another server. In this case access the websites admin tool from your local host. On the page Settings you can change the web sites location from localhost to its actual address. This should solve the problem.

Sources:

Wednesday, 7 May 2014

Simple Router

For a simple router without IP forwarding a DHCP Server and a Ethernet Bridge are needed. In a first step the Bridge gets installed. Afterwards the DHCP Server is added to the Bridge.

The router will provide a network on the Ethernet interfaces eth2, eth3, eth4 and eth5 with the basic address 192.168.1.0.

Installation Bridge

First install the bridge utils

apt-get install bridge-utils

To configure a bridge, the file /etc/network/interfaces needs to be adapted. The bridge itself can be reached on the address 192.168.1.1 for all clients.

auto br0
iface br0 inet static
address 192.168.1.1
network 192.168.1.0
netmask 255.255.255.0
broadcast 192.168.1.255
bridge-ports eth2 eth3 eth4 eth5

Configuration of the DHCP Server

At first define the interfaced to be used in the file /etc/default/isc-dhcp3-server

INTERFACES="br0"

In a second step the subnet need to be defined. For this, the interface and the address range needs to be defined for each net. All this settings are to be done in the file /etc/dhcp/dhcpd.conf.

authoritative;

default-lease-time 600;
max-lease-time 7200;


subnet 192.168.1.0 netmask 255.255.255.0 {
  range 192.168.1.10 192.168.1.250;
  interface br0;
  option broadcast-address 192.168.1.255;
}

Start and Stop of the service

sudo service isc-dhcp-server restart
sudo service isc-dhcp-server start
sudo service isc-dhcp-server stop

Enable Multicast

To enable multicast groups to be routed over the bridge, the system needs to be able to manage multicast groups. A possible group manager is the pimd.

apt-get install pimd

The configuration file for pimd is /etc/pimd.conf. With pimd -l it's possible to reload the config file and adapt the changes. By default the service is activated for all interfaces. For this use I limited its activity to the bridge by excluding all other interfaces. The current mutlicast groups managed and the interfaces accessed can be shown with pimd -r.

Setup Gateway

To be able to access the internet from the created switch, the hosting computer needs to work as a gateway. With the following commands it's possible to forward the traffic. In my case the eth0 is connected to the internet. Therefore the br0 bridge interface needs to be forwarded to the eth0.

sudo iptables -A FORWARD -o eth0 -i br0 -s 192.168.1.0/24 -m conntrack --ctstate NEW -j ACCEPT
sudo iptables -A FORWARD -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
sudo iptables -t nat -F POSTROUTING
sudo iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

The commands need to be executed everytime after boot up since the iptables are rewritten everytime. This could be realized with a startup script or another approach would be to save the current iptable and reload it after boot up.

Source

Tuesday, 6 May 2014

DHCP Server

How to install a DHCP Server on Ubuntu 12.04

The setup is a Ubuntu PC with 4 Ethernet ports.

eth2, eth3, eth4, eth5

Each port is in a separate subnet.

Install the DHCP-Server

apt-get install isc-dhcp-server

Configuration of the DHCP Server

At first define the interfaced to be used in the file /etc/default/isc-dhcp3-server

INTERFACES="eth2 eth3 eth4 eth5"

In a second step the subnets need to be defined. For this, the interface and the address range needs to be defined for each net. The lease times can be defined global for all nets. To prevent any other DHCP Server to interract with your subnet, the Server is set in authoritative mode.  All this settings are to be done in the file /etc/dhcp/dhcpd.conf.

authoritative;

default-lease-time 600;
max-lease-time 7200;


subnet 192.168.150.0 netmask 255.255.255.0 {
  range 192.168.150.10 192.168.150.250;
  interface eth2;
  option broadcast-address 192.168.150.255;
}


subnet 192.168.151.0 netmask 255.255.255.0 {
  range 192.168.151.10 192.168.151.250;
  interface eth3;
  option broadcast-address 192.168.151.200;
}

subnet 192.168.152.0 netmask 255.255.255.0 {
  range 192.168.152.10 192.168.152.250;
  interface eth4;
  option broadcast-address 192.168.152.255;
}

subnet 192.168.153.0 netmask 255.255.255.0 {
  range 192.168.153.10 192.168.153.250;
  interface eth5;
  option broadcast-address 192.168.153.255;
}

At last the interfaces need to be added to the subnets itself. Therefore just define the interfaces in the file /etc/network/interfaces by adding this lines.

auto eth2
iface eth2 inet static
address 192.168.150.1
netmask 255.255.255.0

auto eth3
iface eth3 inet static
address 192.168.151.1
netmask 255.255.255.0

auto eth4
iface eth4 inet static
address 192.168.152.1
netmask 255.255.255.0

auto eth5
iface eth5 inet static
address 192.168.153.1
netmask 255.255.255.0  

The following commands help to control the DHCP Server when trying out the changes

sudo service isc-dhcp-server restart
sudo service isc-dhcp-server start
sudo service isc-dhcp-server stop

Source:

http://askubuntu.com/questions/201746/dhcp-server-with-multiple-interfaces-on-ubuntu-destroys-default-gateway