Home Assistant USBIP Z-Wave Setup w/ More Robust Restart Management

001-README.md

Files Included:

1. usbipd.service (server/physical device)
2. usbip.service (client/HASS host)
3. udev rules file for client host -- maps USB device to /dev/zwave (add to /etc/udev/rules.d/)
4. Client Manager Script

Setup:

See the original instructions here: https://community.home-assistant.io/t/rpi-as-z-wave-zigbee-over-ip-server-for-hass/23006 also see the notes below in each file.

About the Manager Script on the client

This uses a manager script (basically an expanded init script) on the hass.io host machine to control the USB-IP device and manage the connections.

1. Before connecting: Ping the host and see if it's available. If not, wait and retry using an exponential delay (1s, 2s, 4s, 16s, etc. to 256s). This gives time after, for example, a whole home power outage, where everything comes back at the same time, but you have to wait for the other server to come up first).
2. After confirming the host is there, check if the USB-IP service is available. If it isn't, try to restart the service on the remote machine using SSH. FOR THIS TO WORK you must have Public Key Authorization set up both directions on the 2 machines.
3. After mounting the device, restart the homeassistant docker, if it's already running.

About the server service file

The server's .service file actually includes a line to call the client (via SSH) and attempt to restart the client's service. It will continue on if it fails, but if it succeeds, this will cascade to re-mount the port on the client and restart Home Assistant.

99-zwave-stick.rules

# UDEV RULES FOR HASS.IO HOST MACHINE (ADD TO /etc/udev/rules.d)
SUBSYSTEM=="tty", ATTRS{idVendor}=="0658",  ATTRS{idProduct}=="0200", SYMLINK+="zwave", TAG+="systemd"

usbip.service

# SERVICE FILE FOR USBIP CLIENT ON HASS.IO HOST MACHINE
# UDPATE THE PATH BELOW TO YOUR HOME DIRECTORY. USING EXAMPLE FOR DEFAULT
#   RASPBERRY PI USERS: /home/pi/
# SAVE TO `/lib/systemd/system/` AND RUN `sudo systemctl enable usbip.service` TO ENABLE.

[Unit]
Description=usbip client
After=network-online.target
Wants=network-online.target

[Service]
Type=oneshot
RemainAfterExit=yes
ExecStart=/home/pi/scripts/usbip/usbipManager.sh start
ExecStop=/home/pi/scripts/usbip/usbipManager.sh stop

[Install]
WantedBy=multi-user.target

usbipd.service

# SERVICE FILE FOR USBIP SERVER ON HOST MACHINE WITH USB CONNECTED
# UPDATE LINE 13 TO THE DETAILS FOR YOUR HASS.IO HOST MACHINE
# MAKE SURE THE ROOT USER ON THIS MACHINE CAN USE PUBLIC KEYS TO LOGIN VIA SSH
#   TO THE HASS.IO HOST.
# SAVE TO `/lib/systemd/system/` AND RUN `sudo systemctl enable usbip.service` TO ENABLE.

[Unit]
Description=usbip host daemon
After=network-online.target

[Service]
Type=forking
ExecStart=/usr/sbin/usbipd -D
ExecStartPost=/bin/sh -c "/usr/sbin/usbip bind --$(/usr/sbin/usbip list -p -l | grep '#usbid=0658:0200#' | cut '-d#' -f1)"
ExecStartPost=-/bin/sh -c "/usr/bin/ssh -t pi@192.168.1.2 'sudo systemctl restart usbip.service'"
ExecStop=/bin/sh -c "/usr/sbin/usbip unbind --$(/usr/sbin/usbip list -p -l | grep '#usbid=0658:0200#' | cut '-d#' -f1); killall usbipd"

[Install]
WantedBy=multi-user.target

usbipManager.sh

#!/bin/bash

###################################################################
#Script Name    : usbipManager
#Description    : USB IP Client Manger
#Args           : start / stop / restart / status
#Author         : shbatm
#Email          : support@shbatm.com
#Installation   : Install to a convenient location and update the
#                 path used in usbip.service file.
#                 Make sure you update the variables below
###################################################################

USBIP_SERVER_IP='192.168.1.3'
USB_SERIAL_ID='0658:0200'
REMOTE_USER='pi'
REMOTE_SERVICE='usbipd.service'
HASS_DOCKER_NAME='homeassistant'


ATTEMPTS=8

USBIP="/usr/local/sbin/usbip"
name=`basename $0`

SUDO=''
if (( $EUID != 0 )); then
    SUDO='sudo'
fi

# Backoff script from http://stackoverflow.com/a/8351489/580412
function with_backoff {
  local max_attempts=${ATTEMPTS-5}
  local timeout=${TIMEOUT-1}
  local attempt=0
  local exitCode=0

  while [[ $attempt < $max_attempts ]]
  do
    "$@" > /dev/null 2>&1
    exitCode=$?

    if [[ $exitCode == 0 ]]
    then
      break
    fi

    echo "Failure! Retrying in $timeout.." 1>&2
    sleep $timeout
    attempt=$(( attempt + 1 ))
    timeout=$(( timeout * 2 ))
  done

  if [[ $exitCode != 0 ]]
  then
    echo "Giving up! ($@)" 1>&2
  fi

  echo $exitCode
  return $exitCode
}

check_host() {
    # Check if the USB IP Host is online.
    reachable=$(with_backoff ping -c1 -W1 $USBIP_SERVER_IP)
    if [[ $reachable != 0 ]]
    then
      # TODO: Send WOL or other wakeup command to make sure host is on.
      echo "Error: Host unreachable at $USBIP_SERVER_IP." 1>&2
      exit 1
    fi
    if $SUDO $USBIP list -r $USBIP_SERVER_IP 2>&1 | grep -q 'could not connect'; then
      echo "Could not connect to USBIP Host Service at $USBIP_SERVER_IP." 1>&2

      # Attempt to restart remote service using ssh.
      # Note: Public Key Auth must be setup between the servers.
      echo "Attempting to restart $REMOTE_SERVICE on $USBIP_SERVER_IP..."
      ssh -t ${REMOTE_USER}@${USBIP_SERVER_IP} "sudo systemctl restart $REMOTE_SERVICE"

      # Script exits here because service start on remote host will re-call this script on start.
      exit 1
    else
        USB_BUS_ID=$($SUDO $USBIP list -r $USBIP_SERVER_IP | grep $USB_SERIAL_ID | cut -d: -f1)
        echo "Using USB Bus ID: $USB_BUS_ID"
        return 0
    fi
}

attach_host() {
    $SUDO $USBIP attach -r $USBIP_SERVER_IP -b $USB_BUS_ID
}

restart_hass() {
  if [[ "$(/usr/bin/docker ps -q -f name=$HASS_DOCKER_NAME)" ]]; then
    echo "Home Assistant is running. Restarting..."
    /usr/bin/docker restart $HASS_DOCKER_NAME
  fi
}

is_running() {
    $SUDO $USBIP port | grep '<Port in Use>' -q
}

case "$1" in
    start)
    if is_running; then
        echo "Port is active."
    else
        echo "Attempting connection"
        check_host
        attach_host
        sleep 1
        if ! is_running; then
            echo "Unable to start $name. Unspecified error." 1>&2
            exit 1
        fi
        echo "Successfully started $name."
        restart_hass
    fi
    ;;
    stop)
    if is_running; then
        echo -n "Stopping $name..."
        $SUDO $USBIP detach --port=$($USBIP port | grep '<Port in Use>' | sed -E 's/^Port ([0-9][0-9]).*/\1/') > /dev/null 2>&1
        for i in 1 2 3 4 5 6 7 8 9 10
        # for i in `seq 10`
        do
            if ! is_running; then
                break
            fi
            echo -n "."
            sleep 1
        done
        echo

        if is_running; then
            echo "Not stopped; may still be shutting down or shutdown may have failed."
            exit 1
        else
            echo "Stopped."
        fi
    else
        echo "Not running."
    fi
    ;;
    restart)
    $0 stop
    if is_running; then
        echo "Unable to stop, will not attempt to start"
        exit 1
    fi
    $0 start
    ;;
    status)
    if is_running; then
        echo "Running"
    else
        echo "Stopped"
        exit 1
    fi
    ;;
    *)
    echo "Usage: $0 {start|stop|restart|status}"
    exit 1
    ;;
esac

exit 0