Infrastructure

On Orange Pi 3B, the built-in Bluetooth chip Spreadtrum UWE5622 is connected via UART (/dev/ttyBT0). Unlike USB adapters, it requires: Loading firmware and calibration data before initialization Running hciattach_opi with correct flags Correct startup order: chip initialization first, then BlueZ daemon Symptoms: bluetoothctl scan on → No default controller available btmgmt info → Index list with 0 items hciconfig -a shows hci0, but bluetoothctl doesn’t see it Error org.bluez.Error.Busy when trying to power on Cause: The service orangepi3b-sprd-bluetooth.service runs hciattach_opi with the -n flag (no-detach), which holds the device and prevents BlueZ from registering the controller. ...

PostgreSQL doesn’t support in-place upgrades between major versions (15 → 17, 17 → 18). Data must be migrated logically: via dump and restore. Rationale for importance: ✅ New versions = security fixes, optimizations, new features ✅ Support for modern clients (Nextcloud, Mastodon, Authelia require recent versions) ✅ Predictability: same process for any project Docker complexity: ❌ Can’t just change image tag - data format is incompatible ❌ pg_upgrade requires simultaneous access to old/new binaries - breaks container isolation ✅ Solution: pg_dumpall → new container → psql < dump 📋 Prerequisites Before starting, ensure: ...

Docker Desktop on Windows uses WSL2 with dynamic VHDX files. They grow when adding images/containers but don’t shrink automatically when deleting them. Result: C: drive fills up, even though docker system df shows free space. 💡 Solution: manual VHDX optimization via PowerShell + Docker utility. 📦 Cleanup script Create file # File: $HOME\Scripts\docker-clear-wsl.ps1 $script = @' $LOCAL = "$env:LOCALAPPDATA\Docker\wsl" $VHD1 = Join-Path $LOCAL "disk\docker_data.vhdx" $VHD2 = Join-Path $LOCAL "main\ext4.vhdx" # 1. Docker cleanup docker system prune -f # 2. Reclaim space via official tool docker run --rm --privileged --pid=host docker/desktop-reclaim-space docker rmi docker/desktop-reclaim-space -f # 3. Stop Docker Desktop Get-Process -Name "Docker Desktop","com.docker.backend","com.docker.build" ` -ErrorAction SilentlyContinue | Stop-Process -Force -ErrorAction SilentlyContinue # 4. Shutdown WSL wsl --shutdown # 5. Optimize VHDX files (compact) if (Test-Path $VHD1) { Optimize-VHD -Path $VHD1 -Mode Full } if (Test-Path $VHD2) { Optimize-VHD -Path $VHD2 -Mode Full } # 6. Restart Docker Desktop Start-Sleep -Seconds 2 Start-Process -FilePath "$env:ProgramFiles\Docker\Docker\Docker Desktop.exe" ` -ErrorAction SilentlyContinue '@ $script | Out-File -FilePath "$HOME\Scripts\docker-clear-wsl.ps1" -Encoding UTF8 Run # As Administrator (required for Optimize-VHD) powershell.exe -ExecutionPolicy Bypass -File "$HOME\Scripts\docker-clear-wsl.ps1" 🔍 How it works Step Command What it does 1 docker system prune -f Removes stopped containers, unused images, build cache 2 docker/desktop-reclaim-space Official Docker tool to reclaim space in WSL2 3 Stop-Process Gracefully stops Docker Desktop (otherwise VHDX is locked) 4 wsl --shutdown Fully shuts down WSL, freeing files for optimization 5 Optimize-VHD -Mode Full Compacts VHDX files, returning space to host 6 Start-Process Restarts Docker Desktop Rationale: ...

For home servers and test environments, resource saving is important: containers can be stopped and the system powered off during nights or off-hours. This guide describes a safe method with state preservation and automatic recovery. 💡 Method suits OrangePI, Raspberry Pi, old PCs, and any systems where power efficiency matters. 📦 Container shutdown script Create script # File: /usr/local/bin/stop_containers_and_shutdown.sh cat > /usr/local/bin/stop_containers_and_shutdown.sh << 'EOF' #!/bin/bash # # Script saves running container IDs, # stops them, and initiates system shutdown. # CONTAINERS_FILE="/etc/active_containers.txt" echo "=== $(date '+%Y-%m-%d %H:%M:%S') ===" echo "Starting container shutdown and system power-off script" # Get list of running containers (by ID) RUNNING_CONTAINERS=$(docker ps -q) if [ -n "${RUNNING_CONTAINERS}" ]; then echo "Saving running containers to ${CONTAINERS_FILE}" echo "${RUNNING_CONTAINERS}" > "${CONTAINERS_FILE}" docker stop ${RUNNING_CONTAINERS} echo "Containers stopped." else echo "No running containers." [ -f "${CONTAINERS_FILE}" ] && rm -f "${CONTAINERS_FILE}" fi sleep 10 echo "Shutting down system." /sbin/shutdown -h now EOF Make executable chmod +x /usr/local/bin/stop_containers_and_shutdown.sh How it works Step Description docker ps -q Gets IDs of all running containers > /etc/active_containers.txt Saves list for recovery docker stop Gracefully stops containers (SIGTERM) sleep 10 Allows time for operations to complete shutdown -h now Powers off the system Rationale: ...

Docker Volumes store data independently from containers but require a separate approach for backup. This guide describes universal methods for working with volumes using popular services as examples. 💡 Replace volume names in examples with your own. Methods apply to any containers. 📦 Backup volumes Via docker-volume-backup (recommended) docker run --rm \ -v portainer_data:/backup/portainer_data \ -v postgres_data:/backup/postgres_data \ -v redis_data:/backup/redis_data \ -v /opt/docker/backup:/archive \ --entrypoint backup \ offen/docker-volume-backup:v2 Parameters: Parameter Description -v <volume>:/backup/<name> Map volume to backup directory -v /opt/docker/backup:/archive Where to save archive on host --entrypoint backup Run backup mode --rm Remove container after completion Advantages of this method: ...

Practical guide to OpenWRT configuration for advanced home use. Covers configurations that extend router functionality: DNS-level traffic filtering, secure remote access via WireGuard, metrics monitoring, and automated notifications. 💡 All sensitive values are replaced with <...>. Substitute your own values. 📦 Package installation opkg update # Monitoring: prometheus exporter + modules opkg install \ prometheus-node-exporter-lua \ prometheus-node-exporter-lua-nat_traffic \ prometheus-node-exporter-lua-netstat \ prometheus-node-exporter-lua-openwrt \ prometheus-node-exporter-lua-wifi \ prometheus-node-exporter-lua-wifi_stations # WireGuard: kernel module + tools + LuCI opkg install \ kmod-wireguard \ wireguard-tools \ luci-proto-wireguard # DNS over HTTPS opkg install https-dns-proxy # Debug utilities opkg install curl jq tmux htop Purpose: ...

OrangePI and other ARM single-board computers often use eMMC or SD cards with limited write endurance. Over time, storage fills up, degrades, or fails. This guide describes a method for data recovery and migration to external storage (USB SSD/HDD) via a chroot environment. 💡 Method is universal: works for OrangePI, Raspberry Pi, NanoPi, and other ARM systems. 📦 Preparation Requirements Component Requirements USB drive SSD/HDD, capacity ≥ eMMC data Live image Any Linux with ARM support (optional) Access root or sudo, physical access to board Network Ethernet or WiFi (for remote access) Check connected storage # Show all MMC devices (eMMC, SD card) ls /dev/mmc* # Show all block devices lsblk # Show partitions and mount points df -h Expected output: ...