====== Linux - systemd - Run a script at startup ======

Create a systemd service unit file.

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===== Example to run a script which sets firewall rules =====

Create a file named **/etc/systemd/system/sharewiz-firewall.service**:

<file bash /etc/systemd/system/sharewiz-firewall.service>
[Unit]
Description=Runs the firewall.

[Service]
[Unit]
Description=Runs the firewall.

[Service]
ExecStart=/sharewiz/firewall/firewall.sh
ExecStop=/sharewiz/firewall/firewall-reset.sh
Type=oneshot
RemainAfterExit=yes

[Install]
#WantedBy=multi-user.target
WantedBy=default.target 
</file>

<WRAP info>
**NOTE:**  Ensure that the script that is going to be run is executable.

  * **ExecStart** - this is the script that is run when the service starts.
  * **ExecStop** - this is the script that is run when the service stops.
</WRAP>

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===== Reload and enable the firewall.service unit =====

<code bash>
sudo chmod 644 /etc/systemd/system/sharewiz-firewall.service
sudo systemctl daemon-reload
sudo systemctl enable sharewiz-firewall.service
</code>

<WRAP info>
**NOTE:**  The **systemctl daemon-reload** command reloads all unit files, including the new unit file created for the firewall.
</WRAP>

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