Summary
In this chapter, we have covered how to query the STDOUT
and STDERR
output from your containers using the tool built into Docker, how to ship the messages to an external source, our ELK stack, and how to store the messages even after the container has been terminated. Finally, we have looked at a few of the third-party services who offer services to which you can stream your logs.
So why go to all of this effort? Monitoring isn't just about keeping and querying CPU, RAM, HDD, and Network utilization metrics; there is no point in knowing if there was a CPU spike an hour ago if you don't have access to the log files to see if any errors were being generated at that time.
The services we have covered in this chapter offer the quickest and most efficient insights into what can quickly become a complex dataset.
In the next chapter, we will look at all of the services and concepts we have covered in the book and apply them to some real world scenarios.