Daniel Markstedt
e2735813a3
Refactor the DaynaPort TAP driver around explicit bridge and proxy-ARP profiles. Validate the selected interface and profile before creating piscsi0, attach it only to the preconfigured bridge when appropriate, derive a stable DaynaPort MAC address from the uplink, and make TAP setup and cleanup robust. Add managed host networking profiles for wired bridging and Wi-Fi proxy ARP. Install the PiSCSI NetworkManager templates, profile-management command, parprouted and DHCP relay system services, udev/sysctl hooks, and configuration file so a selected Wi-Fi uplink can provide proxy-ARP networking without altering connectivity during package installation. Expose DaynaPort profiles consistently through the protocol, daemon, scsictl, and web UI. Report interface type, state, and supported modes; require or default explicit mode/interface pairs on attach; present eligible wired-bridge and Wi-Fi proxy-ARP choices; and validate selections before attaching an SCDP device. Package and document the new networking workflow. Add the profile utility and required runtime assets to Debian packages, expand the manual-page set and web manual index, update DaynaPort command help, and extend unit and handler tests for the profile-aware behavior.
PiSCSI NetworkManager profiles
PiSCSI supports two explicitly selected DaynaPort topologies on Raspberry Pi
OS Trixie and Forky with NetworkManager. Installing the PiSCSI package only
installs inert templates, services, and /etc/piscsi/network.conf; it never
creates a bridge, changes an active connection, starts proxy-ARP, or changes
firewall state.
The required parprouted and dhcp-helper packages are suggested rather than
installed automatically. This prevents dhcp-helper's generic service from
binding DHCP on an existing host interface before the user selects proxy-ARP.
Wired bridge
Bridge mode is the protocol-complete choice: it supports DHCP, AppleTalk,
multicast, and non-IP Ethernet protocols. NetworkManager must own the bridge,
the physical Ethernet port, and the bridge address. PiSCSI owns only the
ephemeral piscsi0 TAP membership while a DaynaPort is attached.
From a local console, preview and apply the named profile with:
sudo piscsi-network-profile --dry-run apply bridge eth0
sudo piscsi-network-profile --console-acknowledge apply bridge eth0
The command prints every change, refuses to run without NetworkManager, and
creates only the named PiSCSI wired bridge and PiSCSI wired bridge port
connections. --console-acknowledge is explicit approval and skips the
otherwise required local-terminal APPLY prompt. It can be removed with
sudo piscsi-network-profile --console-acknowledge remove bridge.
For manual configuration, the package provides inert keyfile templates in
/usr/share/piscsi/network/. Substitute unique UUIDs, the physical NIC, and
the physical Ethernet MAC in the templates, copy them to
/etc/NetworkManager/system-connections/ with mode 0600, then reload
NetworkManager. The bridge MAC must remain distinct from the DaynaPort TAP
MAC. The equivalent commands are:
ethernet_mac=$(cat /sys/class/net/eth0/address)
nmcli connection add type bridge ifname piscsi_bridge con-name 'PiSCSI wired bridge' ipv4.method auto ipv6.method auto bridge.stp no 802-3-ethernet.cloned-mac-address "$ethernet_mac"
nmcli connection add type ethernet ifname eth0 master piscsi_bridge
nmcli connection up 'PiSCSI wired bridge'
Replace eth0 with the selected physical Ethernet interface. Verify that the
bridge owns DHCP and the selected Ethernet MAC, and that the physical port has
no independent IP address before attaching a DaynaPort with
mode=bridge:interface=piscsi_bridge.
Wi-Fi proxy ARP
Proxy-ARP exposes a DaynaPort client directly on the Wi-Fi IPv4 LAN. It supports IPv4 unicast and DHCP only. It does not provide IPv6, AppleTalk, multicast, mDNS reflection, or general Ethernet bridging.
Before selecting this profile, remove any legacy PiSCSI NAT/firewall rules manually. The package and profile command never remove, flush, or rewrite iptables/nftables state. Keep a local console or another recovery path: Wi-Fi proxy-ARP cannot replace a broken Wi-Fi association and is not a transparent Ethernet bridge.
Install the suggested dependencies, then preview and apply the profile from a local console:
sudo apt install parprouted dhcp-helper
sudo piscsi-network-profile --dry-run apply proxyarp wlan0
sudo piscsi-network-profile --console-acknowledge apply proxyarp wlan0
Replace wlan0 with the NetworkManager-managed Wi-Fi interface holding the
Pi's global IPv4 lease. The command writes only
/etc/piscsi/network.conf, reloads PiSCSI runtime configuration, and disables
the generic dhcp-helper.service to avoid its UDP/67 conflict. To remove the
PiSCSI selection, use
sudo piscsi-network-profile --console-acknowledge remove proxyarp.
PISCSI_PROXYARP_PROMISC=true is a compatibility option; PiSCSI records and
restores the flag only if it enabled promiscuous mode itself.
The udev rule starts piscsi-proxyarp.service only after PiSCSI creates
piscsi0; it then starts the PiSCSI-owned DHCP relay. The relay conflicts with
the generic dhcp-helper.service to prevent UDP/67 contention. A NetworkManager
dispatcher restarts both PiSCSI services after the selected uplink reconnects
or receives a changed DHCP lease.
Verify an attachment with:
ip -br link show piscsi0
ip -4 addr show dev piscsi0
systemctl status piscsi-proxyarp piscsi-dhcp-relay
journalctl -u piscsi-proxyarp -u piscsi-dhcp-relay -b
On detach, PiSCSI removes only the exact /32 it added to piscsi0, stops
only PiSCSI-owned processes, and restores promiscuous mode only when it had
changed it. It does not flush addresses, routes, or firewall state.
DaynaPort attachment
Always submit a complete mode/interface pair. For example:
scsictl -i 6 -c attach -t scdp -f 'mode=bridge:interface=piscsi_bridge'
scsictl -i 6 -c attach -t scdp -f 'mode=proxyarp:interface=wlan0'
Do not use the retired inet parameter or a comma-separated interface list.
They describe the obsolete NAT/implicit-bridge path and are rejected.