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In last section we learned how to start up a shell inside of a container at the instant that it was

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started.

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By the way if you have a little bit of trouble exiting from this by hitting control C which is usually

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how we exit out of a container remember you can either press controlled D on your keyboard or you can

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just type in exit like so and it will kick you back out.

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Now in this section there's one very small gotcha maybe not even a gotcha but just a very particular

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thing that I want to go over to make sure that it's really crystal clear on how containers behave.

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I want you to recall back to a little bit ago when we were initially talking about what a container

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is.

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Remember that we gave this example of where Chrome had needed a particular version of Python and no

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J.S. needed its own version of Python and we had said that through that name spacing feature we can

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kind of imagine that our hard disk had two little segments carved out of it.

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And anytime chrome tried to access that hard drive it would get its own segment any time no J.S. tried

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to access the hard drive it would get its own different segment and so the thing that wants to make

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sure is really crystal clear is that between two containers they do not automatically share their file

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system.

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We're gonna do a quick demo inside of our terminal just to really confirm that that is the case.

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So I'm going to open up my terminal and I'm going to start up a new instance of that busy box image

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and I'm going to start up a shell inside there.

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So I'll do Docker run dash I.T. Busy Box shell.

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So now I can list my files and folders inside of here and I see just these default folders I'm now going

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to open up a second terminal window and I'm going to start a second container with the same parameters.

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So second turn a window and I'll do Docker run dash I.T. Busy Box SDH now going to open up one more

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terminal window.

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So this is gonna be a third one and inside of here I'll do Docker piece and I can verify that I have

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two separate containers both running a show.

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Now I'm gonna go to the first terminal window and inside of here I'm going to create a new file with

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touch.

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Hi there like so that's going gonna create a new file called Hi there.

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There it is right there I can run less and I'll see the file up here right away.

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Now here's the fun part.

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We're gonna go over these second terminal window and I'll do an Ellis over here as well.

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And of course I am not going to see that file of hi there because these two running containers have

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absolutely completely separate file systems and there's no sharing of data between the two.

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Again this is kind of a small thing but I just want to make sure there was very crystal clear.

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So in general unless you and I specifically form up a connection between two containers we really consider

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them to be more or less completely isolated from each other and totally separate.

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All right.

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So that's pretty much it.

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On the basics of Docker so we're gonna take a quick pause right here.

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We're gonna come back the next section.

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We're gonna start moving on to the next big topic that we're going to cover.

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So I'll see you in just a minute.