ppp_amiga

NOTE: You may prefer amiga_internet to this

With the appropriate USB to serial cable like this one, allow any Amiga with at least 2MiB RAM but probably more like 4MiB, Kickstart version 37 or higher (Workbench 2+), a null modem cable with a 25-pin to 9-pin connector, a working serial port and the appropriate TCP/IP software installed to access the internet or your local area network using any Raspberry Pi.

Requirements

Any Amiga with 2MiB+ RAM, Kickstart V37+ (Workbench 2+) and a working serial port, AmiTCP-3.0b2, a null-modem cable with 25-pin to 9-pin connector and a USB serial converter
Any Raspberry Pi with a working internet connection running Raspberry Pi OS

Role Variables

The following variables should be put in host_vars/localhost/vars

#
# Local network
#
lan_interface: "{{ interface | default(ansible_default_ipv4.interface) }}"
lan_ip: "{{ ip | default(ansible_default_ipv4.address) }}"
lan_network: "{{ network | default(ansible_default_ipv4.network) }}"
lan_netmask: "{{ netmask | default(ansible_default_ipv4.netmask) }}"

#
# Amiga to Raspberry Pi IP configuration
#
ppp_pi_ip: "{{ serial_ip | default('10.168.0.1') }}"
ppp_amiga_ip: "{{ amiga_ip | default('10.168.0.2') }}"

#
# Firewall rules
#
firewall_rules: {
  nat_rules: [
   '-A PREROUTING --in-interface {{ lan_interface }} --protocol tcp --match tcp --dport 356 --jump DNAT --to-destination {{ ppp_amiga_ip }}:356 -m comment --comment="Port forward TCP/356 for Amiga Explorer from the Raspberry Pi to the Amiga"',
   '-A POSTROUTING --out-interface {{ lan_interface }} --jump MASQUERADE -m comment --comment="Set up NAT to allow the Amiga to talk through the Raspberry Pi"',
  ],
  filter_rules: [
    '-A INPUT -i {{ lan_interface }} -s {{ lan_network }}/{{ lan_netmask }} -m state --state NEW -j ACCEPT -m comment --comment="Allow all traffic from the LAN"',
    '-A INPUT -i ppp0 -s {{ ppp_amiga_ip }} -m state --state NEW -j ACCEPT -m comment --comment="Allow traffic to this Raspberry Pi from the Amiga"',
    '-A FORWARD -i ppp0 -o {{ lan_interface }} -j ACCEPT -m comment --comment="Allow traffic from the Amiga to be forwarded through this Raspberry Pi"',
  ],
  mangle_rules: [
  ]
}

Dependencies

No external dependencies

Example Playbook

---
#
# Ansible playbook for installation and configuration of the PPP Amiga bridge
#
# @author: Roger North-Row
# @date:   16/09/2018
#
- hosts: localhost

  become: yes
  connection: local

  roles:
    - { role: ppp_amiga, tags: ppp_amiga_role }

Getting Started (Raspberry Pi)

Install Raspberry Pi OS, you only need the 'lite' version without a GUI

Log in and type the following into your terminal to update your Pi to the latest operating system version and reboot afterwards:

sudo apt update && sudo apt dist-upgrade -y && sudo reboot

Log back in and tidy up after reboot: sudo apt autoremove -y && sudo apt autoclean

Install ansible and git: sudo apt install -y ansible git

Fetch the ansible repo from GitHub: git clone https://github.com/rjnorthrow/amiga-internet.git

Change to the amiga-internet directory

cd amiga-internet

Run the Ansible Script

ansible-playbook ppp_amiga.yml

Getting Started (Amiga)

Any reasonably spec'd Amiga will do, with a working serial port (see Requirements above)

Install AmiTCP

Firstly, make a New Drawer on your hard disk to contain the software, for example Internet. I put this on my System or Workbench partition

Getting the software on to your Amiga may be the tricky bit. I used a Gotek drive, copying the software on to a virtual floppy disk on a USB key with ADF Opus. You can also use Amiga Explorer as you already have the serial cable

You may also need to copy the LhA software in order to unpack AmiTCP-3.0b2.lha. Copy this to your Amiga into the Ram Disk. Run this from the Ram Disk on your Amiga and rename one of the extracted files which matches your processor. For example, rename lha_68020 as lha if you are running on an Amiga 1200. Finally, copy this file to SYS:C

You can now extract the AmiTCP-3.0b2.lha file. Copy it again to your Ram Disk if you have enough RAM (~2.8MiB spare) or to a hard disk partition such as WORK:, open a Shell and type:

RAM:
lha x amitcp#?

The files will be extracted into a directory called AmiTCP-3.0b2. You can now run the installer Install_AmiTCP

When asked, choose the following options:

Intermediate User
Install for Real
Select directory where to install AmiTCP/IP: SYS:Internet/AmiTCP-3.0b2
Do you want to install example Sana-II configuration files? Yes
Select Sana-II configuration files to be copied: Proceed with Copy - you don't need these but it creates the directory for you
Do you want to install Napsaterm fonts, napsa? No
Logging in as 'root' and changing the root's password: Proceed
Log in as super-user (root), Password: Just press Return, we can't log in at this stage
Login incorrect: There is a bug in the installation script, simply close the window
Enter the default user name: Put anything in here, such as your first name
Enter the host name of your computer: Put anything in here, such as Amiga
Enter the domain part of your host name: Put anything in here, such as example.com
The host name will be stored to the environment variable HOSTNAME: Store to ENV(ARC) or Use "setenv", it doesn't matter
Give aliases to your computer: Proceed
Select a SANA-II device driver: ppp.device - not listed? Download and install this
Select unit number: 0
IP address: 10.168.0.2
Give the destination address: 10.168.0.1
Netmask of network: 255.255.255.254
Is this correct? Yes
Select a SANA-II device driver: Proceed
Enter the IP address of the default gateway: 10.168.0.1
Give domain names (one at a time) to search: Proceed
Give domain names (one at a time) to search: Proceed
Enter the IP addresses of the name servers (one at a time): Use your LAN's DNS resolvers, it might be 192.168.0.1 for example
Enter the IP addresses of the name servers (one at a time): Proceed
Do you want the AmiTCP/IP to be started at the system startup? Yes or No depending on your preference
Do you want Installer to make the required changes to your s:user-startup script? Yes (probably!)
Do you want the Inetd to be started at the AmiTCP/IP startup? No
(Read the README)
Installation complete! Proceed

At this point, the software is installed but not configured properly. Take the following steps to configure the software by opening a Shell:

ed S:user-startup - Remove the whole line starting AmiTCP:bin/login as this won't work until the TCP/IP stack is running

ed ENVARC:sana2/ppp0.config - Add the line: serial.device 0 57600 0.0.0.0, this configures ppp0 to use the serial interface

ed SYS:Internet/AmiTCP-3.0b2/db/interfaces - Add the line: ppp DEV=Devs/Networks/ppp.device to bind ppp0 to the ppp device

ed SYS:Internet/AmiTCP-3.0b2/bin/startnet:

Add a new line at the top: online Devs:Networks/ppp.device 0, this brings up the ppp0 interface, configured above
Change run AmiTCP:AmiTCP to run >NIL: AmiTCP:AmiTCP to discard output from the command
Change AmiTCP:bin/ifconfig lo/0 localhost to ifconfig lo0 localhost, fixing the device name, and ifconfig is already in our path
Change AmiTCP:bin/ifconfig Devs:Networks/ppp.device/0 to ifconfig ppp0, keeping the rest of the line

Now ensure that pppd is running on your Raspberry Pi and then reboot your Amiga

In order to tidy up the connection after use, type: offline Devs:Networks/ppp.device 0. This makes sure that the Raspberry Pi end is informed that the connection has been terminated and it will restart the PPP daemon so that you can connect again

Troubleshooting

There are several variables that you can change from the command line, for example if your LAN network clashes with the one set up as the default for the Amiga to Raspberry Pi link (10.168.0.0/24)

Change the Amiga<->Raspberry Pi network

ansible-playbook --extra-vars='serial_ip=192.168.0.1 amiga_ip=192.168.0.2' ppp_amiga.yml

Use a serial cable connected to the GPIO pins rather than USB

ansible-playbook --extra-vars='ppp_serial_device=/dev/ttyAMA0' ppp_amiga.yml

If you are using the wireless rather than the Ethernet connector

ansible-playbook --extra-vars='interface=wlan0' ppp_amiga.yml