View source for MISC-TN-005: Running AWS Greengrass Core on SBCSPG

==Setting up the edge device==
The first thing to do was to rebuild the Linux kernel after adding the missing options⁠ required by GGC, which are detailed [https://docs.aws.amazon.com/en_us/greengrass/latest/developerguide/what-is-gg.html#gg-platforms here].

Once the device was up and running with the fresh Linux kernel, to enable IP routing to the Internet, the default gateway was setup like this:
<pre class="board-terminal">
root@sbcspg:~# route add default gw 192.168.0.254 eth0
</pre>

<code>/etc/resolv.conf</code> was edited to add a typical DNS entry:
<pre class="board-terminal">
root@sbcspg:~# cat /etc/resolv.conf
nameserver 8.8.8.8
</pre>

Then, the root file system had to be configured according to the requirements described [https://docs.aws.amazon.com/en_us/greengrass/latest/developerguide/setup-filter.other.html here].

AWS documentation was a little bit confusing about the Node.JS and Java requirements. Both were installed, just in case. With regard to Java, OpenJDK 1.8.0 was installed.

The following guides were useful to install some of the required packages:
*https://tecadmin.net/install-latest-nodejs-npm-on-debian/
*https://tecadmin.net/install-python-3-7-on-ubuntu-linuxmint/
*https://www.digitalocean.com/community/tutorials/how-to-install-java-with-apt-on-debian-9

To setup <code>cgroups</code>, [https://raw.githubusercontent.com/tianon/cgroupfs-mount/master/cgroupfs-mount this script] was used.

Finally, a couple of file system setting had to be tuned, too. They are hardlink and softlink protections. For more details about these settings, please refer to the following links:
*https://www.tecmint.com/protect-hard-and-symbolic-links-in-centos-rhel/
*https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_MRG/1.3/html/Realtime_Tuning_Guide/sect-Realtime_Tuning_Guide-General_System_Tuning-Setting_persistent_tuning_parameters.html

Finally, the recommended certificate was installed
<pre class="board-terminal">
sudo wget -O root.ca.pem https://www.amazontrust.com/repository/AmazonRootCA1.pem
</pre>

To verify that the device is setup properly, it is recommended to use the dependency checker script provided by AWS itself. The following image shows the output of the checker executed on SBCSPG after completing the configuration.


[[File:GGC-checker.png|thumb|center|600px|Output of the GGC dependencies checker]]


As shown, only one check is highlighted, which refers to the kernel version. To run GGC 1.9.2, it is recommended a 4.4 kernel version or later. Although checker's report didn't warn about the use of containers, we verified that GGC couldn't work on top of SBCSPG's 4.1.15 Linux kernel. Because a newer kernel was not available for SBCSPG at the time of this writing, to work around this issue, the [https://docs.aws.amazon.com/greengrass/latest/developerguide/lambda-group-config.html#lambda-containerization-groupsettings default Lamba functions containerization] was disabled.

In order to make the checker happy, two symbolic links were created as well:
<pre class="board-terminal">
lrwxrwxrwx 1 root root  4 Jul 30 16:50 /usr/bin/java8 -> java
lrwxrwxrwx 1 root root  6 Jul 30 16:52 /usr/bin/nodejs8.10 -> nodejs
</pre>