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shekhargulati / 52-technologies-in-2016

Let's learn a new technology every week. A new technology blog every Sunday in 2016.
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Feedback: Week 8 CoreOS #11

Open shekhargulati opened 8 years ago

shekhargulati commented 8 years ago

Please provide your feedback by posting a comment against this issue.

brianredbeard commented 8 years ago

CoreOS isn't built on ChromeOS. They both use the same SDK, but technically Gentoo is the upstream. CoreOS maintains their own eBuilds and keeps a portage mirror on GitHub.

shekhargulati commented 8 years ago

thanks @brianredbeard I will make the changes.

llarsson commented 8 years ago

That journalctl command you write in the end only happens to work by lucky accident. Had fleet scheduled the unit onto another machine, you would not be able to access it via journalctl, which only works on the local host.

fleetctl journal -f hello.service would work, regardless of where the unit has been scheduled.

The divide between what is operating locally (systemd and journalctl), and what fleet does to unify them into a cluster-wide system is probably one of the more conceptually difficult topics in CoreOS.

You might also need to mention that SSH agent forwarding (with your key added) is really useful, since that is required for many of the fleetctl commands that need to access other hosts (such as pulling info from the journal, or actually logging in to them for you via SSH, to go to where the unit is running).