Saturday 4 August 2018

How to send files to a Raspberry Pi from Windows 10

This post refers to a Raspberry Pi 3b+ running Raspbian Stretch.

A quick note; I’m going to use the PuTTy Secure Copy client (PSCP) because I have the PuTTy tools installed on my Windows machine.

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In this example I want to copy a file to the Raspberry Pi home directory from my Windows machine. Here’s the command format to run:

pscp -pw pi-password-here filename-here pi@pi-ip-address-here:/home/pi

Replace the following with the appropriate values:

  • pi-password-here with the Pi user password
  • filename-here with the name of the file to copy
  • pi-ip-address-here with the IP address of the Raspberry Pi


The following example includes the –r option to copy over a directory – actually a Plex plugin – rather than a single file to the Pi.

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How to check that AWS Greengrass is running on a Raspberry Pi

This post refers to a Raspberry Pi 3 B+ running Raspbian Stretch.

To check that AWS Greengrass is running on the device run the following command:

ps aux | grep -E 'greengrass.*daemon'

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A quick reminder of Linux commands.

The ps command displays status information about active processes. The ‘aux’ options are as follows:

a = show status information for all processes that any terminal controls
u = display user-oriented status information
x = include information about processes with no controlling terminal (e.g. daemons)

The grep command searches for patterns in files. The –E option indicates that the given PATTERN – ‘greengrass.*daemon’ in this case - is an extended regular expression (ERE).

Friday 3 August 2018

Automatically starting AWS Greengrass on a Raspberry Pi on system boot

This post covers the steps necessary to get AWS Greengrass to start at system boot on a Raspberry Pi 3+ running Raspbian Stretch. The Greengrass software was at version 1.6.0.

I don’t cover the Greengrass installation or configuration process here. It is assumed that has already been done. Refer to this tutorial for details.

What we are going to do here is use systemd to run Greengrass on system boot.

Step 1

Navigate to the systemd/system folder on the Raspberry Pi.

cd /etc/systemd/system/

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Step 2

Create a file called greengrass.service in the systemd/system folder using the nano text editor.

sudo nano greengrass.service

Copy in to the file the contents described in this document.

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Save the file.

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Step 3

Change the permissions on the file so they are executable by root.

sudo chmod u+rwx /etc/systemd/system/greengrass.service

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Step 4

Enable the service.

sudo systemctl enable greengrass

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Step 5

You can now start the Greengrass service.

sudo systemctl start greengrass

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You can check that Greengrass is running.

ps –ef | grep green

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Reboot the system and check that Greengrass started after a reboot.

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Friday 3 August 2018