# Controller Node

![Controller Node](/files/PiKi3OqPyzjea5nYDrB4)

## Verify Requirements

#### Check the operating system

Currently we only support Ubuntu 20.04.5 LTS. Verify the operating system by

```bash
$ cat /etc/os-release
NAME="Ubuntu"
VERSION="20.04.5 LTS (Focal Fossa)"
```

#### Check disk space

Here, we see that there is more than 20GB free in the root file system.

```
[root@dev01 ~]# df -h /
Filesystem               Size  Used Avail Use% Mounted on
/dev/mapper/cl_dev-root  228G  135G   94G  60% /
```

#### Check available memory

We see that total memory is more than 8G.

```
[root@dev01 ~]# free -h
              total        used        free      shared  buff/cache   available
Mem:           125G        3.6G        106G         39M         15G        121G
Swap:          4.0G          0B        4.0G
```

### Set up Linux users and permissions

We need somewhere to run the tools, and an account to run them as. We recommend not using the `root` account to do so. Ensure you have a non-root user account, with paswordless sudo configured. We will refer to this account as `deploy-user`, and their group as `deploy-group`. Replace these with your own values.

How to make the user `expeca` use sudo without password. Add it to the very last line.

```
$ sudo visudo
...
expeca    ALL = (ALL) NOPASSWD: ALL
```

#### Ensure permissions and groups

```
# Create and join deploy-group
[deploy-user@dev01 ~]$ sudo groupadd <deploy-group>
[deploy-user@dev01 ~]$ sudo usermod -a -G <deploy-group> <deploy-user>

# Create and join docker group
[deploy-user@dev01 ~]$ sudo groupadd docker
[deploy-user@dev01 ~]$ sudo usermod -a -G docker <deploy-user>
```

Log out and back in to refresh group membership, then verify.

```
[deploy-user@dev01 ~]$ groups
... <deploy-group> docker
```

#### Set directory permissions

For this example, we'll be putting files into `/opt/`, so we need to ensure that it can be read and written by members of `deploy-group`

```
[deploy-user@dev01 ~]$ sudo chown root:<deploy-group> /opt
[deploy-user@dev01 ~]$ sudo chmod g+rw /opt
```

### Install dependencies

Now we need to install some dependencies, then check out and set up chi-in-a-box

```
# Install Dependencies
sudo apt update && sudo apt install -f -y \
    python3 \
    python3-venv \
    jq \
    git
```

### Configure networking

Apart from the management interface, there are 2 ethernet ports available on the controller machine, simillar to the figure, we create 4 virtual interfaces with 2 bridges.

Create the file `/etc/systemd/network/20-veth-internal.netdev` and insert:

```
[NetDev]
Name=veth-internala
Kind=veth
[Peer]
Name=veth-internalb
```

Create the file `/etc/systemd/network/20-veth-public.netdev` and insert

```
[NetDev]
Name=veth-publica
Kind=veth
[Peer]
Name=veth-publicb
```

Create the virtual interfaces by restarting `networkd`

```
sudo systemctl restart systemd-networkd
```

Assume `MGMT_IF` is the reserved interface with the static ip `MGMT_IP` and the gateway `MGMT_GW_IP` for ssh connection to the controller. Configure netplan by editing the config file `/etc/netplan/00-installer-config.yaml`:

```
network:
  ethernets:
  eno8403: {}
  ens1f0: {}
  ens1f1: {}
  veth-publica: {}
  veth-publicb: {}
  veth-internala: {}
  veth-internalb: {}
  <MGMT_IF>:
    addresses:
    - <MGMT_IP>
    gateway4: <MGMT_GW_IP>
    nameservers:
       search:
       - expeca
       addresses:
       - <MGMT_GW_IP>
    dhcp4: false
    optional: true
  bridges:
  brpublic:
    interfaces:
    - ens1f1
    - veth-publica
    addresses:
    - 10.0.87.10/24
  brinternal:
    interfaces:
    - ens1f0
    - veth-internala
    addresses:
    - 10.20.111.10/23
    - 192.168.2.1/16
  version: 2
```

Apply the changes by running `sudo netplan generate && sudo netplan apply`.


---

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