After spending some time trying to install Redmine, I'll share the outcome. I tried installing from debian package, but that somehow always failed, and the package is quite old.
What we need:
SQLite3 ruby 1.8.7 RubyGems 1.6 And of course, Redmine (1.2.1)
First of all, make sure we have all libraries etc.
apt-get install build-essential libssl-dev libruby sqlite3 libsqlite3-dev
Let's install Ruby:
wget ftp://ftp.ruby-lang.org/pub/ruby/1.8/ruby-1.8.7-p72.tar.gz tar -xzf ruby-1.8.7-p72.tar.gz cd ruby-1.8.7-p72 ./configure make make install
And RubyGems:
wget http://rubyforge.org/frs/download.php/74445/rubygems-1.6.2.tgz tar -xzf rubygems-1.6.2.tgz ruby rubygems-1.6.2/setup.rb
Gems we need:
gem install rake -v=0.8.7 --no-rdoc --no-ri gem install rails -v=2.3.14 --no-rdoc --no-ri gem install sqlite3 --no-rdoc --no-ri gem install -v=0.4.2 i18n --no-rdoc --no-ri
And finally, redmine:
wget http://rubyforge.org/frs/download.php/75097/redmine-1.2.1.tar.gz tar -xzf redmine-1.2.1.tar.gz -C /usr/share cd /usr/share/redmine-1.2.1
Put this in config/database.yml:
production: adapter: sqlite3 dbfile: db/redmine.db
And setup database (we are still in redmine-1.2.1 folder):
rake generate_session_store rake db:migrate RAILS_ENV=production rake redmine:load_default_data RAILS_ENV=production
Finally, run WEBrick server:
script/server -e production &
Or if you want to run it as a daemon
script/server -e production -d
That's it. Navigate to http://YOUR_DOMAIN_OR_IP:3000 and you should see Redmine
Outcome OpenVZ:
# free total used free shared buffers cached Mem: 196608 87260 109348 0 0 0 -/+ buffers/cache: 87260 109348 Swap: 0 0 0
Outcome Xen:
# free total used free shared buffers cached Mem: 91936 89272 2664 0 3272 15908 -/+ buffers/cache: 70092 21844 Swap: 262136 2388 259748
Not exactly great, but it works :D
This is tested on Debian Squeeze, haven't tried it on any other system. If something goes wrong you probably have to apt-get something and reinstall Ruby.
You'll also need to configure email if you want to fully use it (http://www.redmine.org/projects/redmine/wiki/EmailConfiguration).
I know WEBrick is not the greatest solution, but I'm not sure if this would work on nginx with 96MB limit.