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In all these commands we've been running with Docker create and start.

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There's kind of one oddity that I want to show you really quickly.

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Let's do a container creation and then a start and you'll see some kind of weird behavior.

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I'm gonna run a docker create Busy Box and then we're gonna setup that ping command again.

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So I'll say ping Google dot com that's going to create the container.

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I can then copy the idea right here and do Docker start and paste that idea and you'll notice that I

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did not put in the dash a.

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So I have not attached this container when I run that command.

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I see the idea of the container echoed back to me.

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And then I can do a docker logs and paste that idea in and I'll see that.

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Yep it is in fact running the pin command.

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And if I do the docker P.S. command I can see up that container is running and it's continuing to execute

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the pin command.

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Now there's just one kind of odd thing here.

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How do we actually stop this container.

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Remember the pin command is going to essentially go on forever and we have to actually send it a signal

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until it Hey ping command please stop.

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Like you're all done.

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No need to reach out to Google anymore.

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So we need to figure out a way to stop this running container in the past we've just been hitting control

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C on our keyboard or even allowed the container to automatically stop itself as was the case with the

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Echo command.

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So in order to stop a container that seems to be running amuck on its own we can issue either the docker

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stop command or the docker kill command.

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Both these are going to stop the running container but they look like they kind of do the same thing

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here so what's the difference between them.

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Well here's what happens behind the scenes when you issue a docker stop command a hardware signal is

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sent to the process.

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The primary process inside that container in the case of Docker stop.

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We send a sig term message which is short for terminate signal.

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It's a message that's going to be received by the process telling it essentially to shut down on its

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own time sic term is used.

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Any time that you want to stop a process inside of your container and shut the container down and you

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want to give that process inside there a little bit of time to shut itself down and do a little bit

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of cleanup.

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A lot of different programming languages have the ability for you to listen for these signals inside

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of your codebase.

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And as soon as you get that signal you could attempt to do a little bit of cleanup or maybe save some

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file or emit some message or something like that.

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On the other hand the docker kill command issue is a sig kill or kills signal to the primary running

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process inside the container so kill it essentially means you have to shut down right now and you do

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not get to do any additional work so ideally we always stop a container with the docker stop command

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in order to get the running process inside of it a little bit of time to shut itself down.

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Otherwise if it feels like the container has locked up and it's not responding to the docker stop command

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then we could issue Docker kill instead.

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Now one kind of little oddity or interesting thing about Docker stop when you issue Docker stop to a

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container.

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If the container does not automatically stop in 10 seconds then Docker is going to automatically fall

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back to issuing the docker kill command.

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So essentially at Docker stop is us being nice but it's only got 10 seconds to actually shut down.

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So let's now try using these commands on that kind of runaway container that we have right now.

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So again do Docker P.S. And I'll see that the pinging google doc command hears me pin Koogle dot com

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container is still running.

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So going to take the idea right there and I'll issue Docker stop and then I'll paste that idea in and

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then we're going to wait and notice how we're kind of waiting here.

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We're going to end up waiting just about ten seconds.

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We're waiting 10 seconds because it turns out that the ping command does not properly respond to a sig

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term message.

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The ping command doesn't really have the ability to say oh yeah I understand you want me to shut down

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the ping command is rather an analyst term for it.

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The ping command wants to do its own thing and just wants to run forever.

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And so after we waited those 10 seconds eventually the kill signal was sent to it telling it Hey ping

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you're done.

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Get out of here.

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Shut yourself down.

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And so that's why we had to wait a couple of seconds.

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Let's now take that container idea again.

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We're going to start the container back up and try killing it this time with using Docker kill Sol first.

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Start the container back up with Docker start.

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I'll pace the idea in and then I'll issue a docker kill and paste the idea again and this time you're

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going to see that's it instantly dead.

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No Grace Period.

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Just get out of here.

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All right.

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So that's it.

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That's the two commands that we're going to use for closing down containers that are running.

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Remember you can always get the idea the container ahead of time with Docker P.S. you can copy the I.D.

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and then run either dock or stop or Docker kill.

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And in general I do recommend use Docker stopped to give the processes inside there a chance to shut

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down and if they don't shut down nice nicely nicely as we saw with the pin command.

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Eventually Docker is going to fall back to issuing a kill on the container instead.

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All right.

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So that's pretty much it.

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Let's take another brief pause and continue in the next section.