Step by Step Installation: Ubuntu

This manual was tested with Ubuntu Server 10.04.1 LTS is currently updated for Ubuntu Server 12.04 and SQL-Ledger Version 3. It shows how to set up a simple SQL-Ledger server that runs in a local network. For servers available in the Internet, additional security measures are required.

First you have to download the ISO file of the operating system. Go to the Ubuntu homepage and download, according to your needs, Ubuntu 12.04 LTS in the 32 or in the 64 bit version.

You can install Linux either on 'real' hardware or in a virtual machine running on your computer.

Existing hardware To be able to install the operating system, you have to burn the downloaded ISO-file to a CD. Don't copy the file to the CD, choose the ISO burn function in your burning software.

Virtual Machine

To create a virtual server, you can use for example Virtualbox that you get here.

Start Virtualbox, click “New”, give your machine the name “SQL-Ledger” and choose Linux and Ubuntu for operating system. You don't need much memory, 256 - 512 MB are enough. For the virtual hard disk, use the default settings, just press next and finish until your disk and server are created. Before you start, you have to change the network settings. Open the network adapter and change it to “Bridged Adapter”. Now you can turn the machine on. The First Run Wizard appears and asks for the installation media. Show him the previously downloaded ISO file.

Turn on your computer with the Linux CD in the drive or the virtual machine with the ISO file connected.

• change the language on the welcome screen
• select Install
• choose your language and location
• change the keyboard layout if it's not US
• set the host name to “my-server” or a name you choose
• accept or change the time zone setting as required
• choose “Guided - use entire disk” for partitioning
• say Yes that you want to write changes to disk

Wait some minutes until the basic installation is finished.

• set your user name, account name and password
• don't encrypt your home directory
• you probably don't have to specify an Http proxy
• select no automatic updates
• don't choose software to install, we will make this manually
• install Grub: Yes
• on a real computer, eject the CD, on a virtual machine, disconnect the ISO file.
• select Continue

Now the system restarts.

Login to the server with your user name and password. To be able to install the software, we have to change to the “root” account. In this way, we get administrator rights. Type:

sudo -i

and enter your password. With the following command, we install the packages we need for SQL-Ledger:

apt-get install ssh acpid apache2 postgresql libdbi-perl libdbd-pg-perl git-core gitweb postfix mailutils texlive

The installation needs some time. While installing postfix (the mail server), the system asks you about the mail configuration.

• select “satellite system”
• for SMTP relay host, enter the name of your mail server (smtp…)

If you use another language than English, you may want to install an additional package that supports hyphenation in your language, for example

apt-get install texlive-lang-german

You get a list of all available language packs with:

apt-cache search texlive-lang

Or, if you know from beginning that you will use several different languages or special LaTeX functions, install the complete package:

apt-get install texlive-full

We will install SQL-Ledger in the folder /usr/local/sql-ledger. For this, we change to /usr/local:

  cd /usr/local
  

You have two versions to choose between, either the original SQL-Ledger, developed by DWS systems, or the Enhanced SQL-Ledger, provided by Ledger123.

To install the original SQL-Ledger, type:

  git clone git://github.com/Tekki/sql-ledger.git
  

Because of a security leak , the template editor is disabled in the above repository. It is recommended not to use the master, but the full branch:

  cd /usr/local/sql-ledger
  git checkout -b full origin/full
  

The full branch contains some additional features like WLprinter (see below) or an extended admin interface.

For the Ledger123 type:

  git clone git://github.com/ledger123/ledger123.git sql-ledger
  

Next, you have to create a spool directory, change the access rights to some files and folders and copy sql-ledger.conf.default to sql-ledger.conf.

  cd /usr/local/sql-ledger
  mkdir spool
  chown -hR www-data.www-data users templates css spool
  cp sql-ledger.conf.default sql-ledger.conf
  

If the remote repositories changed, you update your installation with

  cd /usr/local/sql-ledger
  git pull
  

In the full branch of the original SQL-Ledger, you have the possibility to update the software using the Software Administration function in the Admin interface. Before it works, you have to give the web server the right to call the git commands. For this, type

  visudo
  

Then add the following line to the user privilege section:

  www-data ALL=(ALL) NOPASSWD: /usr/bin/git

CUPS is the printing system for Linux. You have to install it if the SQL-Ledger server should be able to print to printers in your network.

 apt-get install cups hplip hpijs cupsys-driver-gutenprint
  cupsctl --remote-admin
  

Now you can call from your browser the CUPS web interface at

https://ip_of_your_server:631

and add your printer. Remember the name you give to your printer. Then open sql-ledger.conf

nano /usr/local/sql-ledger.conf

and move to “# available printers”. There you see an example of two printers. Replace them with your own printer or printers. The name on the left side is the name you will see in SQL-Ledger, the one on the right side immediately after -P is the name by which the printer is known to the operating system.

WLprinter

WLprinter is a program that allows to print from SQL-Ledger directly and without further installation or configuration to printers connected to client computers. On the client side, it requires Java and on Windows machines Adobe Reader. After the installation, SQL-Ledger automatically provides an additional printer “WLprinter”.

Original Version

WLprinter is part of the full branch. If you followed the above instructions, this program already installed on your server. It is recommended that you copy the config file wlprinter.conf.default to wlprinter.conf, so you can edit it:

 cp wlprinter.conf.default wlprinter.conf

Ledger123

WLprinter isn't available for Ledger123.

If you didn't add printers with CUPS and edit sql-ledger.conf before, open it now with

 nano /usr/local/sql-ledger.conf

and change the printer definition to

%printer = ( );

Edit the Postgresql database configuration.

nano /etc/postgresql/9.1/main/pg_hba.conf

Change the line

local    all    all    peer

to

local    all    all    trust

Restart the database

service postgresql-9.1 restart

Create a user for SQL-Ledger

su postgres -c "createuser -d -S -R sql-ledger"

Your web server has to know where to find SQL-Ledger. We add a new configuration file and restart the server.

cd /etc/apache2/sites-available/
wget https://raw.github.com/Tekki/sql-ledger/full/doc/sql-ledger.httpd.conf
cd ../sites-enabled/
ln -s ../sites-available/sql-ledger.httpd.conf 001-sql-ledger
service apache2 restart

It should now be possible to access SQL-Ledger. As you didn't specify an address for your server, it was received from DHCP. Enter the following command:

ifconfig eth0

You see the address after “inet addr:”. In a private network, it will be something starting with “192.168…”. Open your web browser, enter this address followed by “/sql-ledger”. The SQL-Ledger login screen has to appear.

There are some additional components that make working with the SQL-Ledger server more comfortable.

Samba is a file server for Windows PCs. If you install it, you are able to connect to the server with its name instead of the IP address from your Windows computer.

apt-get install samba If you followed our example and work on Windows, you can click on the following link to connect to your server:

http://my-server/sql-ledger

If you chose another name, use

http://another_name/sql-ledger

SQL-Ledger can use different printers to print its documents. If you want print to shared printers connected to Windows workstations, install:

apt-get install samba-client Linux probably has no driver for your Windows printer. In this case use WLprinter.

Webmin is a web based administration interface for Linux. It is very convenient for a lot of administration tasks.

cd /tmp
wget http://www.webmin.com/download/deb/webmin-current.deb
apt-get install libapt-pkg-perl apt-show-versions libnet-ssleay-perl openssl libauthen-pam-perl libpam-runtime libio-pty-perl
dpkg --install webmin-current.deb

If you have installed the Samba server, Webmin is now available at

https://my-server:10000

The Webmin server needs some instants (10 seconds or more) to start up. Just wait until the login screen appears and log in with your Linux user name and password.

In the default configuration, your server gets its IP address dynamically via DHCP. This address may change from time to time. You probably want to give it a fixed address, so you can access it always in the same way.

If you open the config file with

nano /etc/network/interfaces

it looks like this:

# The primary network interface
auto eth0
iface eth0 inet dhcp

If you want to give your server the fixed address 192.168.1.10 and your internet router has the address 192.168.1.1, you have to change the file the following way:

iface eth0 inet static
address 192.168.1.10
netmask 255.255.255.0
broadcast 192.168.1.255
network 192.168.1.0
gateway 192.168.1.1

With this change, the server looses the possibility to configure the name servers automatically. Many routers work as name servers, so in most cases it's enough to type:

echo "nameserver 192.168.1.1" > /etc/resolv.conf

After that, restart the network services with

service networking restart

If you installed Webmin, you can make these changes in the Networking–Network Configuration tab.