Slinger on my QNAP works using SysV initialization script.

[patrodyne]

First, my thanks to GerryDazoo for providing his excellent Slinger project.

This is a description of my successful installation of the Slinger server on my QNAP TS-251+ Network Attached Storage (NAS) device.

General Audience

Of interest to a more general audience may be the SysV initialization script listed at the bottom of this discussion. I use that script to launch the Slinger service. That script should work on any *nix device with SysV initialization. Feel free to skip to slingbox_server.sh, even if you are not a QNAP owner.

QNAP Audience

Disclaimer: Although many experienced users customize their QNAP device using techniques described below, you are fully responsible for the outcome of taking any of these actions to modify your device (including data and/or functional loss)! Read more at QNAP NAS Community Forum

QNAP NAS is a family of 24x7 file servers that feature a Linux based OS called QTS. There are many models and this discussion refers to the TS-251+. QTS provides a web console and SSH access. This discussion assumes that you are familiar with SSH and the QTS operating system. In particular, you should know that QTS uses BusyBox to provide the usual Linux CLI commands, common on embedded systems. QTS launches from firmware and configures the top-level file hierarchy (/bin, /etc, /opt, /usr, /var, ...) in memory and dynamically, on each reboot. BusyBox commands are often simpler and fewer than what you may know from a full Linux distro but are generally adequate. On start-up, the firmware can be augmented using QNAP's autorun.sh script and files from the NAS's shared persistent volumes.

My Environment:

• SlingBox 350
• Slinger V4.01
• QNAP TS-251+
  • OS: QTS 5.1.1
  • Kernel: Linux 5.10.60-qnap x86_64 GNU/Linux
  • CPU: Intel(R) Celeron(R) CPU J1900 @ 1.99GHz
  • Memory: 8 GB
  • Python 3.10.4
  • BusyBox v1.24.1

Hint: Before you start, check and update QTS to the latest version. In any case, restart your device and monitor how long a normal reboot takes. My device takes 5-10 minutes.

Python

In QTS, Python3 is installed from the web console as an application.

Slinger Installation

Download the Slinger zip to your NAS and ssh into it as the superuser (admin). Unzip the archive to a folder on a permanent drive. For example, /share/CACHEDEV1_DATA/Slinger. Configure Slinger using the setup instructions. Copy and paste the slingbox_server.sh, listed at the bottom of this discusssion, into the same folder. Edit that script to configure the dir and cmd variables. The user can be skipped when running the service as admin. Set permissions:

chmod 774 slingbox_server.sh

Verify that python3 is available:

# python3 -V 
Python 3.10.4

Hint (OBSOLETE): You may need to set some symlinks. This is where you need to have some experience with QTS, most owners only use the web console for typical multi-media stuff. As a coder, you may need to do some reading, be patient and experiment slowly.

ln -s $SHARE/.qpkg/Python3/python3 /mnt/ext/opt/python3
ln -s /mnt/ext/opt/python3/bin/python3 /usr/local/bin/python3
ln -s /mnt/ext/opt/python3/bin/pip3 /usr/local/bin/pip3

Note: Here SHARE represents your data share path, for example SHARE=/share/CACHEDEV1_DATA.

Hint (REVISED): You may need to 'dot in' the Python3 profile:

. /etc/profile.d/python3.bash

Next, test the new script:

# ./slingbox_server.sh status
Stopped
# ./slingbox_server.sh start
Starting slingbox_server.sh
# ./slingbox_server.sh status
Running
# ./slingbox_server.sh stop
Stopping slingbox_server.sh...
Stopped

SysV Initialization

On a typical SysV system, you create these symlinks to permanently start/stop your service when the system reboots:

ln -s "$SHARE/Slinger/slingbox_server.sh" /etc/init.d/slingbox_server.sh
ln -s /etc/init.d/slingbox_server.sh /etc/rcS.d/QS190slingbox_server
ln -s /etc/init.d/slingbox_server.sh /etc/rcK.d/QK100slingbox_server

However, these paths do not survive when QTS reboots. Thus, you need to learn about the QTS autorun.sh feature. An example of my script is listed below.

In QTS web console...
QTS / Control Panel / Hardware
Enable: Run user defined startup processes (autorun.sh)

RECOMMENDATION

If this is your first time using autorun.sh, I recommend that you start with a stub, like this:

#!/bin/sh
echo "autorun.sh: START" >/dev/kmsg
echo "autorun.sh: FINISH" >/dev/kmsg

Then use the QTS web console to restart your NAS. My device takes 5-10 minutes to reboot, be patient! Use ssh to connect and display the kernel messages. Scroll and look for your messages. Hint: autorun.sh runs out of init_nas (at least on my TS-251+).

# dmesg
...
[  268.635681] [S98init_nas] start
[  274.384903] autorun.sh: START
[  274.553159] autorun.sh: FINISH
[  281.015690] [S98init_nas] end
...

Once, you verify that you have a functioning autorun.sh script then you can slowly add more commands.

SysV Initialization: QTS autorun.sh

#!/bin/sh
#
# Name: autorun.sh
# See: https://www.qnap.com/en/how-to/faq/article/running-your-own-application-at-startup
# 
# Edit: autorun.sh
#   sudo -i
#   mount $(/sbin/hal_app --get_boot_pd port_id=0)6 /tmp/config
#   cd /tmp/config
#   vim autorun.sh
#   umount /tmp/config
#
# QTS / Control Panel / Hardware
#   Enable: Run user defined startup processes (autorun.sh)
#

echo "autorun.sh: START" >/dev/kmsg

SHARE=/share/CACHEDEV1_DATA

#
# Python3
#
echo "autorun.sh: python3" >dev/kmsg
. /etc/profile.d/python3.bash
# ln -s $SHARE/.qpkg/Python3/python3 /mnt/ext/opt/python3
# ln -s /mnt/ext/opt/python3/bin/python3 /usr/local/bin/python3
# ln -s /mnt/ext/opt/python3/bin/pip3 /usr/local/bin/pip3

#
# slingbox_server
#
echo "autorun.sh: slingbox_server" >dev/kmsg
#ln -s "$SHARE/Slinger/slingbox_server.sh" /etc/init.d/slingbox_server.sh
ln -s /etc/init.d/slingbox_server.sh /etc/rcS.d/QS190slingbox_server
ln -s /etc/init.d/slingbox_server.sh /etc/rcK.d/QK100slingbox_server
$SHARE/Slinger/slingbox_server.sh start >/dev/kmsg 2>&1

echo "autorun.sh: FINISH" >/dev/kmsg

exit 0

General Audience

This SysV initialization script can be configured to start/stop your slingbox_server.py.

SysV Initialization: slingbox_server.sh

#!/bin/sh
### BEGIN INIT INFO
# Provides:          slingbox_server
# Required-Start:    $remote_fs $syslog
# Required-Stop:     $remote_fs $syslog
# Default-Start:     2 3 4 5
# Default-Stop:      0 1 6
# Description:       SlingBox Server Service
### END INIT INFO

#
# This is a System V initialization script to start/stop slingbox_server during
# system start and system stop. Typically, this script is put into the
# slingbox_server home folder with the following symlinks to it:
#
# ln -s "$SHARE/Slinger/slingbox_server.sh" /etc/init.d/slingbox_server.sh
# ln -s /etc/init.d/slingbox_server.sh /etc/rcS.d/S96slingbox_server
# ln -s /etc/init.d/slingbox_server.sh /etc/rcK.d/K04slingbox_server
#
# Notes:
#
#   SHARE is the installation directory (see dir below).
#   "S96" is your choice for a late starting process.
#   "K04" is your choice for an early stopping process.
#   Your actual "/etc/rc*" folders may have different names on your system;
#   for example, some system use "rc0-6 to specify the run levels and
#   the S/K symbolic links are both placed in the same run-level folder.
#

dir="INSTALLPATH/Slinger"
cmd="python3 slingbox_server.py"
#user="slingbox"

name=`basename $0`
pid_file="/var/run/${name%.*}.pid"
stdout_log="/var/log/${name%.*}.log"
stderr_log="/var/log/${name%.*}.err"

get_pid() {
    cat "$pid_file"
}

get_pid_regex() {
    echo "^`get_pid`[^0-9]"
}

is_running() {
    [ -f "$pid_file" ] && [ -n "$(ps | grep `get_pid_regex` | grep -v grep)" ] > /dev/null 2>&1
}

case "$1" in
    start)
    if is_running; then
        echo "Already started"
    else
        echo "Starting $name"
        cd "$dir"
        if [ -z "$user" ]; then
            sudo $cmd >> "$stdout_log" 2>> "$stderr_log" &
        else
            sudo -u "$user" $cmd >> "$stdout_log" 2>> "$stderr_log" &
        fi
        echo $! > "$pid_file"

        if ! is_running; then
            echo "Unable to start, see $stdout_log and $stderr_log"
            exit 1
        fi
    fi
    ;;
    stop)
    if is_running; then
        echo -n "Stopping $name.."
        kill `get_pid`
        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"
            if [ -f "$pid_file" ]; then
                rm "$pid_file"
            fi
        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