Deploy a CoreOS running Kubernetes environment. This particular guild is made to help those in an OFFLINE system, wither for testing a POC before the real deal, or you are restricted to be totally offline for your applications.
To setup CentOS PXELINUX environment there is a complete [guide here](http://docs.fedoraproject.org/en-US/Fedora/7/html/Installation_Guide/ap-pxe-server.html). This section is the abbreviated version.
2.`vi /etc/xinetd.d/tftp` to enable tftp service and change disable to 'no'
```conf
disable = no
```
3. Copy over the syslinux images we will need.
```shell
su -
mkdir -p /tftpboot
cd /tftpboot
cp /usr/share/syslinux/pxelinux.0 /tftpboot
cp /usr/share/syslinux/menu.c32 /tftpboot
cp /usr/share/syslinux/memdisk /tftpboot
cp /usr/share/syslinux/mboot.c32 /tftpboot
cp /usr/share/syslinux/chain.c32 /tftpboot
/sbin/service dhcpd start
/sbin/service xinetd start
/sbin/chkconfig tftp on
```
4. Setup default boot menu
```shell
mkdir /tftpboot/pxelinux.cfg
touch /tftpboot/pxelinux.cfg/default
```
5. Edit the menu `vi /tftpboot/pxelinux.cfg/default`
```conf
default menu.c32
prompt 0
timeout 15
ONTIMEOUT local
display boot.msg
MENU TITLE Main Menu
LABEL local
MENU LABEL Boot local hard drive
LOCALBOOT 0
```
Now you should have a working PXELINUX setup to image CoreOS nodes. You can verify the services by using VirtualBox locally or with bare metal servers.
## Adding CoreOS to PXE
This section describes how to setup the CoreOS images to live alongside a pre-existing PXELINUX environment.
1. Find or create the TFTP root directory that everything will be based off of.
* For this document we will assume `/tftpboot/` is our root directory.
2. Once we know and have our tftp root directory we will create a new directory structure for our CoreOS images.
3. Download the CoreOS PXE files provided by the CoreOS team.
This configuration file will now boot from local drive but have the option to PXE image CoreOS.
## DHCP configuration
This section covers configuring the DHCP server to hand out our new images. In this case we are assuming that there are other servers that will boot alongside other images.
1. Add the `filename` to the _host_ or _subnet_ sections.
```conf
filename "/tftpboot/pxelinux.0";
```
2. At this point we want to make pxelinux configuration files that will be the templates for the different CoreOS deployments.
```conf
subnet 10.20.30.0 netmask 255.255.255.0 {
next-server 10.20.30.242;
option broadcast-address 10.20.30.255;
filename "<otherdefaultimage>";
...
# http://www.syslinux.org/wiki/index.php/PXELINUX
host core_os_master {
hardware ethernet d0:00:67:13:0d:00;
option routers 10.20.30.1;
fixed-address 10.20.30.40;
option domain-name-servers 10.20.30.242;
filename "/pxelinux.0";
}
host core_os_slave {
hardware ethernet d0:00:67:13:0d:01;
option routers 10.20.30.1;
fixed-address 10.20.30.41;
option domain-name-servers 10.20.30.242;
filename "/pxelinux.0";
}
host core_os_slave2 {
hardware ethernet d0:00:67:13:0d:02;
option routers 10.20.30.1;
fixed-address 10.20.30.42;
option domain-name-servers 10.20.30.242;
filename "/pxelinux.0";
}
...
}
```
We will be specifying the node configuration later in the guide.
## Kubernetes
To deploy our configuration we need to create an `etcd` master. To do so we want to pxe CoreOS with a specific cloud-config.yml. There are two options we have here.
1. Is to template the cloud config file and programmatically create new static configs for different cluster setups.
2. Have a service discovery protocol running in our stack to do auto discovery.
This demo we just make a static single `etcd` server to host our Kubernetes and `etcd` master servers.
Since we are OFFLINE here most of the helping processes in CoreOS and Kubernetes are then limited. To do our setup we will then have to download and serve up our binaries for Kubernetes in our local environment.
An easy solution is to host a small web server on the DHCP/TFTP host for all our binaries to make them available to the local CoreOS PXE machines.
To get this up and running we are going to setup a simple `apache` server to serve our binaries needed to bootstrap Kubernetes.
This is on the PXE server from the previous section:
These are based on the work found here: [master.yml](/docs/getting-started-guides/coreos/cloud-configs/master.yaml), [node.yml](/docs/getting-started-guides/coreos/cloud-configs/node.yaml)
Now that we have our new targets setup for master and slave we want to configure the specific hosts to those targets. We will do this by using the pxelinux mechanism of setting a specific MAC addresses to a specific pxelinux.cfg file.
Refer to the MAC address table in the beginning of this guide. Documentation for more details can be found [here](http://www.syslinux.org/wiki/index.php/PXELINUX).
```shell
cd /tftpboot/pxelinux.cfg
ln -s coreos-node-master 01-d0-00-67-13-0d-00
ln -s coreos-node-slave 01-d0-00-67-13-0d-01
ln -s coreos-node-slave 01-d0-00-67-13-0d-02
```
Reboot these servers to get the images PXEd and ready for running containers!
## Creating test pod
Now that the CoreOS with Kubernetes installed is up and running lets spin up some Kubernetes pods to demonstrate the system.
For more complete applications, please look in the [examples directory](https://github.com/kubernetes/kubernetes/tree/{{page.githubbranch}}/examples/).
