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So now let's talk about

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the Multi-Attach feature of the EBS volumes.

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So as the name indicates,

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the Multi-Attach feature allows you to attach

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the same EBS volume to multiple EC2 instances

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in the same availability zone.

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So what does that mean?

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That means that, well,

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we have multiple EC2 instances,

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and we have an io2 volume

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with the Multi-Attach feature enabled.

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Then this volume can be attached

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to multiple EC2 instances at a time,

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which is something that is only available

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for the io1 and the io2 family of EBS volumes.

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Now, each instance will have

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full read and write permissions

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to the high-performance volume.

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And so that means that they can all

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write and read at the same time.

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So the use case for this is

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you have higher application availability

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in case of a clustered Linux application,

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for example, using Teradata,

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or if your application must manage

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concurrent rights operation.

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So just so you know,

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this Multi-Attach feature is only available

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from within a specified availability zone, of course.

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It doesn't allow you to attach an EBS volume

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from one AZ to another AZ.

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Another limitation of Multi-Attach is

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that it is up to 16 EC2 instances at a time

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that can be attaching the same volume.

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And this is something you have to know for the exam,

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so be careful to that 16 number.

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Finally, for it to work,

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you must use a file system

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that is going to be cluster-aware.

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So it's a different file system than XFS or EX4.

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And this is just a little bit more details,

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but in case you wanted to use this feature, now you know.

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Okay, that's it for this lecture, I hope you liked it.

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And then we'll see you in the next lecture.