Django on RedHat or CentOS
Computing · django · Linux centos · django · nginx · redhat
I am normally using Debian, Ubuntu or even Suse for deploying Django, but a recent customer needed to deploy on Red Hat Enterprise Server 5.
We decided beforehand to test deployment on RHEL5 and also on CentOS 5.4 and so these instructions should work for both environments. NginX will be used as the webserver.
The first thing I like to do is to upgrade the repository and add EPEL. This wasn’t needed I found on the RedHat box I was using, but was needed on CentOS but your mileage might vary. It should be noted that we made the system as up to date as possible with patches and yum updates.
I won’t be covering the database setup, it is assumed that this is already setup and done. I also won’t be covering the actually placing of the Django application anywhere.
[cc lang=“bash”]
cd ~
rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/i386/epel-release-5-3.noarch.rpm
yum repolist
yum update
yum search zlib
yum install zlib-devel*
yum install gcc make
[/cc]
Python 2.4 ships with both RHEL5 and CentOS 5 and is needed for the packaging environment YUM so I would advise not to replace it but just compile and install 2.5.5 (or 2.6) next to it.
[cc lang=“bash”]
mkdir src
cd src
wget http://www.python.org/ftp/python/2.5.5/Python-2.5.5.tgz
tar fxz Python-2.5.5.tgz
cd Python-2.5.5
./configure
make
make install
cd ~/src
sh setuptools-0.6c11-py2.5.egg
[/cc]
Now we need to build and install NginX. I choose this primarily because of my experience with it, (I have used Apache2 a lot but its archaic ) and because of its speed.
[cc lang=“bash”]
yum install pcre-devel.i386 openssl-devel.i386
wget http://nginx.org/download/nginx-0.7.65.tar.gz
tar fxz nginx-0.7.65.tar.gz
./configure –sbin-path=/usr/local/sbin –conf-path=/etc/nginx/nginx.conf –pid-path=/var/run/nginx.pid –error-log-path=/var/log/nginx/error.log –http-log-path=/var/log/nginx/access.log –with-http_ssl_module –with-http_flv_module –with-cc-opt=”-I /usr/include/pcre”
make
make install
vim /etc/init.d/nginx
sudo chmod +x /etc/init.d/nginx
/sbin/chkconfig nginx on
/sbin/chkconfig –list nginx
[/cc]
There is a decent RedHat init.d script here: http://wiki.nginx.org/RedHatNginxInitScript, but remember that I have changed the installation location above so you will need to change the location in that script of nginx from /usr/sbin/nginx to /usr/local/sbin/nginx
You will also need a nginx.conf configuration script for /etc/nginx/ or you could roll your own using sites-available, sites-enabled pattern. I will attach the script soon.
Now with Python 2.5 installed we can install Django and other requirements:
[cc lang=“bash”]
easy_install-2.5 Django
easy_install-2.5 django-nose
easy_install-2.5 http://dist.repoze.org/PIL-1.1.6.tar.gz
easy_install-2.5 flup
[/cc]
I am using easy_install here as that is the most widely used tool, but pip with a requirements file is a better solution.
Now we need a database adapter. I am using PostgreSQL 8.4.2, if you are using MySQL, Oracle or some other database you will need to follow the recommended route for the Python adapter.
[cc lang=“bash”]
yum search psycopg2
yum install python-psycopg2.i386 (This will install for the old Python)
yum install postgresql-devel
cd ~/src
wget http://initd.org/pub/software/psycopg/psycopg2-2.0.13.tar.gz
tar xvfz psycopg2-2.0.13.tar.gz
cd psycopg2-2.0.13
vim setup.cfg
[/cc]
Change the location of pg_config:
[cc lang=“bash”]
pg_config=/usr/bin/pg_config
[/cc]
And now install:
[cc lang=“bash”]
python2.5 setup.py build
python2.5 setup.py install
[/cc]
Then you need to install your application. This is really specific to your needs. I choose to install the files in /opt/cantemo/application-name as that is specific to our solutions, but RedHat style might mean that you wish to install somewhere else.
Lastly you will want to have your application start easily and also make sure that it starts if the machine ever reboots. To do this I am going to install the start-stop-daemon that is used on Debian based linux distros on Redhat. I read some threads that it will but there is no ETA on that.
You should download the initd script for Django from http://code.djangoproject.com/wiki/InitdScriptForLinux. Change the RUN_AS user to the user on RedHat that you are going to use for running Nginx. By default this is apache.
[cc lang=“bash”]
cd ~/src
wget http://developer.axis.com/download/distribution/apps-sys-utils-start-stop-daemon-IR1_9_18-2.tar.gz
tar -xzf apps-sys-utils-start-stop-daemon-IR1_9_18-2.tar.gz
cd ~/src/apps/sys-utils/start-stop-daemon-IR1_9_18-2
gcc start-stop-daemon.c -o start-stop-daemon
cp start-stop-daemon /usr/local/sbin/
chmod +x /usr/local/sbin/start-stop-daemon
vim /etc/init.id/fastcgi
chmod +x /etc/init.d/fastcgi
/etc/init.d/fastcgi start
ps ax
/etc/init.d/fastcgi stop
/sbin/chkconfig –add fastcgi
/sbin/chkconfig –list fastcgi
[/cc]
Lastly make sure that your application directories have the correct user permissions but you should be able to start everything by issuing the following commands:
[cc lang=“bash”]
/etc/init.d/nginx start
/etc/init.d/fastcgi start
[/cc]
Eric Florenzano posted a nice tutorial on deploying django using FastCGI so also check that out, but I didn’t have much luck with daemontools on CentOS, and didn’t bother trying on RedHat. I suggest instead using start-stop-daemon. Check it out for other hints and tips though, particularly on prefork vs. threaded, pip, and more nginx configuration tips.
comments powered by Disqus