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Crontab not starting python program

I created a python program, "test.py" and have saved it under /home/pi/. When I go to run it in the terminal using "python3 /home/pi/test.py" it runs properly and speaks "hello world". The code is shown below.
import os
import alsaaudio
m = alsaaudio.Mixer()
current_volume = m.getvolume()
m.setvolume(35)
os.system("espeak 'Hello World!'")
I want this program to start whenever my raspberry pi starts up. I tried to add this line in crontab but my raspberry pi doesn't execute the command. Does anyone know why my program won't execute?
#reboot python3 /home/pi/test.py
Here is an image of the syslog

can you try adding the full path to python3:
#reboot /usr/bin/python3 /home/pi/test.py
Also, regarding wanting to run the code on when the device boots - you can run your code as a service.
To do so create a .service file under /etc/systemd/system (for example my-code.service)
Enter the following inside the file
[Unit]
Description=My python service
After=network.target
[Service]
ExecStart=/usr/bin/python3 -u test.py
WorkingDirectory=/home/pi
[Install]
WantedBy=multi-user.target
Finally enable the service (in order for it to run on boot)
sudo systemctl enable my-code
If you want to run it independently you can also run
sudo systemctl start my-code

pkill -f not working from inside shell script

I have a shell script called kill.sh that helps me restart a python script I've written. I normally use pkill -f main.py to kill my forever-running python script. However, when I wrote it into a shell script it does not work.
My script
pkill -f main.py
ps aux | grep main.py # Still shows the process running.
While just executing pkill -f main.py in bash command line works as expected. Why is this?

This is not a satisfactory answer, as I cannot find out the root cause of why pkill -f does not work in a script. I ended up using a systemd Service file to manage my python process. Here's an example fyi.
[Unit]
Description=Service Name
[Service]
Environment=PYTHONUNBUFFERED=1
ExecStart=/path/to/python /path/to/python/script.py
Restart=on-failure
RestartSec=5s
WorkingDirectory=/python/project/dir/
Name the file main.service and place it in /lib/systemd/system/
Running the service systemctl start main.service
Stop the service systemctl stop main.service
Restart the service systemctl restart main.service
Show status and output systemctl status main.service -l
Now I don't have to worry about multiple processes running. If the program dies it'll even restart.

Using scapy sniff on reboot in Raspberrypi (Systemd)

TL;DR: Why does Scapy's sniff not run at reboots from systemd?
I have the following code running on my RPI3 that specifically looks for network requests. This uses the inbuilt ETH0 wifi:
monitorConnections.py
def arp_detect(pkt):
print("Starting ARP detect")
logging.debug('Starting ARP detect')
if pkt.haslayer(ARP):
if pkt[ARP].op == 1: #network request
PHONE_name = "Unknown"
PHONE_mac_address = ""
if pkt[ARP].hwsrc in known_devices.keys():
print ("Known Phone Detected")
logging.debug('Known Phone Detected')
# Grab name and mac address
PHONE_mac_address = pkt[ARP].hwsrc
PHONE_name = known_devices[PHONE_mac_address]
print ('Hello ' + PHONE_name)
logging.debug('Hello ' + PHONE_name)
else:
# Grab mac address, log these locally
print ("Unknown Phone Detected")
logging.debug('Unknown Phone Detected')
PHONE_mac_address = pkt[ARP].hwsrc
print (pkt[ARP].hwsrc)
print("Start!")
print (sniff(prn=arp_detect, filter="arp", store=0))
When I run this via the command
python2 monitorConnections.py
This runs as designed, however I have been trying to put this in a daemon, conscious that it needs to run after the internet connection has been established. I have the following setting in my service:
MonitorConnections.service
[Unit]
Description=Monitor Connections
Wants=network-online.target
After=network.target network-online.target sys-subsystem-net-devices-wlan0.device sys-subsystem-net-devices-eth0.device
[Service]
Type=simple
ExecStart=/usr/bin/python2 -u monitorConnections.py
ExecStop=pkill -9 /usr/bin/autossh
WorkingDirectory=/home/pi/Shared/MonitorPhones
Restart=always
User=root
StandardOutput=console
StandardError=console
[Install]
WantedBy=multi-user.target
In order to find the services that I need my script to run after, I ran this command:
systemctl list-units --no-pager
To find the following services to add to my service under 'After' - these corresspond with the ethernet
services (I imagine!)
sys-subsystem-net-devices-wlan0.device
sys-subsystem-net-devices-eth0.device
As far as I can tell, this is running successfully. When I save everything and run the following:
sudo systemctl daemon-reload
sudo systemctl restart monitorConnections
This kickstarts the script beautifully. I have then set my script to run at reboot like so:
sudo systemctl enable monitorConnections
And reboot, I can see that it runs the print statement "Start", however then does not seem to run anything within the 'sniff' command, however when running
sudo systemctl -l status monitorConnections
I can see that the script is active - so it has not errored!
My question: Why is it that scapy's sniff does not seem to run at reboot? Have I missed something out
I'm honestly at the end of my wits as to what is wrong - any help about this would be greatly appreciated!

RPI3's wifi driver does not have monitoring mode. After weeks of debugging, this was narrowed down to be the issue. I hope this helps someone else.

Kafka Producer and Consumer Scripts to Run automatically

I have a Django project and I am using pykafka. I have created two files named producer.py and consumer.py inside the project. I have to change directory into the folder where these are present and then separately run python producer.py and consumer.py from the terminal. Everything works great.
I deployed my project online and the web-app is running so I want to run the producer and consumer automatically in the background. How do i do that?
EDIT 1: On my production server I did nohup python name_of_python_script.py & to execute it in the background. This works for the time being but is it a good solution?

You can create a systemd service MyKafkaConsumer.service under /etc/systemd/system with the following content:
[Unit]
Description=A Kafka Consumer written in Python
After=network.target # include any other pre-requisites
[Service]
Type=simple
User=your_user
Group=your_user_group
WorkingDirectory=/path/to/your/consumer
ExecStart=python consumer.py
TimeoutStopSec=180
Restart=on-failure
RestartSec=5
[Install]
WantedBy=multi-user.target
In order to start the service (and configure it in order to run on boot) you should run
systemctl enable MyKafkaConsumer.service
systemctl start MyKafkaConsumer.service
To check its status:
systemctl status MyKafkaConsumer
And to see the logs:
journactl -u MyKafkaConsumer -f
(or if you want to see the last 100 lines)
journalctl -u MyKafkaConsumer -n 100
You'd need to create a similar service for your producer too.
There are a lot of options for systemd services. You can refer to this article if you need any further clarifications. It shouldn't be hard to find guides and additional material online though.

Creating a startup service for python script to run as root in Arch Linux

I have a python script that I want to run on start up as root. I believe that I need to add it as a service file but I don't know if it has root permission. This is how i have my service file. The python file wont run unless in root.
[Unit]
Description= Description here
[Service]
Type=simple
ExecStart=/usr/bin/python /home/script.py
StandardOutput=null
[Install]
WantedBy=multi-user.target
Alias=script.service
Any help will be appreciated.

Got it to work. After I removed the root check from my python script everything worked fine, i also removed the Type=simple part from the service file. After those two things it worked fine.
the root check part i removed was.
from os import getenv
user = getenv("SUDO_USER")
if user is None:
print ("This program needs to run as root")
exit(0)
and the service file now looks like this
[Unit]
Description= Description here
[Service]
ExecStart=/usr/bin/python /home/script.py
StandardOutput=null
[Install]
WantedBy=multi-user.target
Alias=script.service
I still don't understand why I needed to take out the root check, program ran fine when I used sudo python script.py. For some reason when the script was ran with systemctl it would fail the root check.

Systemd runs multi-user services as root, so I don't see what help do you need.