jailmaker/templates/router/README.md

Router Jail Template

Host a subordinate LAN using nftables and dnsmasq for DHCP, DNS, routing, and netboot infrastructure.

router   laptop  desktop
  |         |       |
  +-- LAN --+-------+
       |
      { TrueNAS SCALE }
                     |
    +-----+-----+-- LAN2 --+------+------+-------+
    |     |     |          |      |      |       |
   RPi1  RPi2  RPi3      NUC01  NUC02  NUC03  CrayYMP

Example usage: deploy a flock of headless/diskless Raspberry Pi worker nodes for Kubernetes; each netbooting into an iSCSI or NFS root volume.

Setup

Use the TrueNAS SCALE administrative UI to create a network bridge interface. Assign to that bridge a physical interface that's not shared with the host network.

Use the dnsmasq-example.conf file as a starting point for your own dnsmasq settings file(s). Copy or mount them inside /etc/dnsmasq.d/ within the jail.

Optional: place assets in the mounted /tftp/ directory for netbooting clients.

Optional: attach more jails to this same bridge to host e.g. a K3s control plane, an nginx load balancer, a PostgreSQL database...

Check out the config template file. You may provide it when asked during ./jlmkr.py create or, if you have the template file stored on your NAS, you may provide it directly by running ./jlmkr.py create --start --config /mnt/tank/path/to/router/config myrouterjail.

Additional Resources

There are as many reasons to host LAN infrastructure as there are to connect a LAN. This template can help you kick-start such a leaf network, using a TrueNAS jail as its gateway host.

For those specifically interested in netbooting Raspberry Pi, the following external links might help you get started.

• Network Booting a Raspberry Pi 4 with an iSCSI Root via FreeNAS; the title says it all
• Raspberry Pi Network Boot Guide covers more Raspberry Pi models; written for Synology users
• pi_iscsi_netboot and prep-netboot-storage are scripts showing preparation of boot assets and iSCSI root volumes

Good luck!