November 2018
Beginner
230 pages
6h 4m
English
Content preview from Docker Quick Start Guide
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The HEALTHCHECK instruction
The HEALTHCHECK instruction, which is a fairly new addition to the Dockerfile, is used to define the command to run inside a container to test the container's application health. When a container has a HEALTHCHECK, it gets a special status variable. Initially, that variable will be set to starting. Any time a HEALTHCHECK is performed successfully, the status will be set to healthy. When a HEALTHCHECK is performed and fails, the fail count value will be incremented and then checked against a retries value. If the fail count equals or exceeds the retries value, the status is set to unhealthy. The syntax of the HEALTHCHECK instruction is as follows:
# HEALTHCHECK instruction syntaxHEALTHCHECK [OPTIONS] CMD command ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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