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In this video, we'll talk about some tools that allow you to monitor what is going on

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in your file system.

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We're talking about technical tools that are giving deep insight in the workings of your

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file system.

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Now, the tools are file system specific.

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On EXE4 file systems, Tune2FS will show and optimize your EXE file systems.

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There is DumpE2FS, which will dump EXE file system metadata.

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And XFS Admin is what you can use to monitor XFS properties.

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Let me show you.

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For this demo, I'm going to connect to my Ubuntu server for the simple reason that Ubuntu

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comes with EXE and CentOS, as well as Red Hat, are coming with XFS by default.

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So let me open a root shell, because really for these commands, we do need superuser privileges.

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And lsblk is showing me what?

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Showing me my root logical volume right here.

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And I have an SCA2.

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Let's investigate SCA2 using Tune2FS minus L on dev SCA2.

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And what do we see?

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We see technical information about the file system.

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Now, this is not the information that you will be using on a daily basis.

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But sometimes, it can be useful to check out file system features, for instance.

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There is this feature for the extended attributes.

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And these extended attributes are required to store additional information.

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Or what do you think of the default mount options, user XATR or ACL?

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Let's imagine that you are trying to set an attribute using CHATR, or you are trying to

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use setFACL to set file system access control lists, and it doesn't work.

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Well, that is a moment where you want to dive into the file system organization to

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check if there is ACL support.

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And here you can see it.

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For the rest of it, you can see more technical metadata.

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An interesting one about EXT is that EXT has an inode count.

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So there is 114,688 inodes.

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Now one feature of EXT is that inodes are static.

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They are created when you create your file system.

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And that means that you can run out of inodes.

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Now fortunately, on this system, we still have a lot of inodes available.

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So we are far from this system.

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But if ever you get an inode unavailable message, well, requesting information about your file

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system might be convenient.

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You can get even more data by using the dump utility.

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So dump E2FS on dev SCA2, for instance, is giving detailed information about block groups.

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This is really going deep, and many administrators never get there.

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As you can see in the beginning, we have the same output as tune2fs-l.

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But then we get into the block groups.

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EXT file systems are organized in block groups for more logical storage of your files.

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And if you want details about these block groups, well, you can see it right here.

