Installing Chef 10 Server on Debian

First of all add the Opscode repository to apt: 
echo "deb `lsb_release -cs`-0.10 main" | tee /etc/apt/sources.list.d/opscode.list

Then add the GPG key:
mkdir -p /etc/apt/trusted.gpg.d
gpg –keyserver –recv-keys 83EF826A
gpg –export | tee /etc/apt/trusted.gpg.d/opscode-keyring.gpg > /dev/null

Then install the Chef Server:
apt-get update
apt-get upgrade
apt-get install opscode-keyring
apt-get install chef chef-server

While the installation you're asked to enter the URL of your Chef server, just enter http://<your-ip-address>:4000 putting in the IP address of your machine:

Screenshot 1

Then edit the file /etc/default/jetty and comment out this line:

Now you need to setup authentication and knife:
mkdir -p ~/.chef
cp -v /etc/chef/validation.pem /etc/chef/webui.pem ~/.chef

chown -R $USER ~/.chef
knife configure -i

Follow the instructions:

Screenshot 2

Using knife client list you now should have this output:
root@chef:/# knife client list

Then login to chef server via Web interface: http://<your-ip-address>:4040

Screenshot 3

Screenshot 4