OpenWRT 25.12 image builder for the Banana Pi BPI-R4 (MediaTek MT7988A / Filogic 880) with the BPI-R4-NIC-BE14 WiFi 7 card.
Produces bootable SD card images and sysupgrade .itb files with configuration baked in at build time. A CLI tool (wrtstack) handles build and flash operations for each router in the fleet.
| Component | Detail |
|---|---|
| Board | Banana Pi BPI-R4 |
| SoC | MediaTek MT7988A (Filogic 880) |
| WiFi card | BPI-R4-NIC-BE14 (mt7996 / WiFi 7) |
| OpenWRT target | mediatek/filogic |
| OpenWRT profile | bananapi_bpi-r4 |
# Clone with submodule
git clone --recurse-submodules git@github.com:farscapian/wrtstack.git
cd wrtstack
# One-time setup: install deps, init submodule, add shell alias
./setup.sh
source~/.bashrc
# Build
wrtstack build gw-wrt
wrtstack build office-wrt
# Build + flash
wrtstack flash gw-wrt --device=/dev/sdb
wrtstack flash office-wrt # prompts for device if omitted- Ubuntu 24.04+ or 26.04 (apt-based)
- ~25 GB free disk space
- Internet access
- Run as a normal user (not root)
wrtstack build <router> [OPTIONS] Build firmware image
wrtstack flash <router> [OPTIONS] Build then flash to SD card
wrtstack help Show help
| Option | Description |
|---|---|
--device=/dev/sdX | Block device for flash (or prompted interactively) |
--jobs=N | Parallel make jobs (default: nproc) |
--workdir=DIR | Build directory (default: openwrt-bpi-r4/) |
| Name | Role | Env file | Backup dir |
|---|---|---|---|
gw-wrt | Gateway router | env/gw-wrt.env | backups/gw-wrt/ |
office-wrt | Office AP | env/office-wrt.env | backups/office-wrt/ |
Drop a LuCI-exported .tar.gz into backups/<router>/. The most recent one is auto-selected and extracted into the OpenWRT files/ overlay. The backup is authoritative for all identity (hostname, IPs, VLANs, WiFi, WireGuard keys, etc.).
# Generate a backup: LuCI -> System -> Backup / Flash Firmware -> Download backup
cp ~/Downloads/backup-gw-*.tar.gz backups/gw-wrt/
wrtstack flash gw-wrt --device=/dev/sdbWhen no backup exists, HOSTNAME, LAN_IP, and SSH_PUBKEY in the env file are used to generate a minimal first-boot config. Set the full production configuration via LuCI after first boot.
# Uncomment in env/gw-wrt.env:# HOSTNAME=gw# LAN_IP=192.168.4.2# SSH_PUBKEY="ssh-ed25519 AAAA..."
wrtstack build gw-wrtEach router has env/<router>.env defining its build config:
# Mode B identity -- used only when no backup exists in backups/<router>/#HOSTNAME=gw#LAN_IP=192.168.4.2#SSH_PUBKEY="ssh-ed25519 AAAA..."
PACKAGES="hostapd-openssl dawn luci-app-dawn ..."
PACKAGES_REMOVE="wpad-basic-wolfssl wpad-wolfssl wpad-openssl"Env files are tracked in git (they contain no secrets -- backup tarballs hold sensitive material and are gitignored).
Built to openwrt-bpi-r4/bin/targets/mediatek/filogic/:
| File | Use |
|---|---|
*-bananapi_bpi-r4-sdcard.img.gz | Bootable SD card image |
*-bananapi_bpi-r4-squashfs-sysupgrade.itb | LuCI / sysupgrade OTA |
The BPI-R4-NIC-BE14 ships with a factory-defective EEPROM that caps 2.4 GHz and 5 GHz TX power at ~6-7 dBm. wrtstack uses the upstream OpenWRT fix (landed in 25.12.3): a device tree overlay (mt7988a-bananapi-bpi-r4-wifi-be14) that provides correct calibration data.
wrtstack bakes /etc/uci-defaults/99-bpi-r4-be14-wifi into every image. On first boot, this script runs fw_setenv bootconf_extra mt7988a-bananapi-bpi-r4-wifi-be14. U-Boot loads the overlay on the next boot, restoring TX power to ~20 dBm.
The router auto-reboots ~10 seconds after first boot to activate the overlay -- no manual reboot needed. After the second boot, verify with iw dev (expect ~20 dBm) and fw_printenv bootconf_extra.
| Interface | Address | Role |
|---|---|---|
| br-lan.1 | 192.168.1.1 | LAN |
| br-lan.20 | 192.168.2.1 | homenet VLAN |
| br-lan.30 | 192.168.3.1 | serversNet VLAN |
| br-lan.60 | 192.168.6.1 | guestNet VLAN |
| br-lan.70 | 192.168.8.1 | UIotNet VLAN |
| WAN | DHCP | Uplink |
Domain: ancapistan.io | WireGuard VPN | DDNS (Namecheap) | WPA3-SAE + 802.11r
| Interface | Address | Role |
|---|---|---|
| br-lan.1 | 192.168.1.2/24 | LAN (gw: 192.168.1.1) |
| br-lan.20 | 192.168.2.2/24 | homenet |
| br-lan.30 | DHCP | serversNet |
| br-lan.60 | 192.168.6.2/24 | guestNet |
Dnsmasq, firewall, and odhcpd disabled -- pure AP mode. Fast roaming via 802.11r / DAWN (mobility_domain=a1b2 across all radios).
# 1. Create env file
cp env/office-wrt.env env/new-router.env
# edit env/new-router.env# 2. Create backup directory
mkdir -p backups/new-router
touch backups/new-router/.gitkeep
# 3. Build
wrtstack build new-routeropenwrt-bpi-r4/ tracks openwrt/openwrt at a pinned commit.
# Update to latest upstream
git submodule update --remote openwrt-bpi-r4
git add openwrt-bpi-r4
git commit -m "bump openwrt submodule"Every wrtstack build run is safe to repeat:
- apt: no-op for already-installed packages
- files/ overlay: sha256-gated; rebuilt only when backup or env vars change
.config: regenerated from profile + env on every run- make: incremental; only changed components rebuild