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'
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).