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Hey guys and welcome back.

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So the last tool that I want to show you for the purposes of our backup operations that

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we have to know for the LPIC2 examination is the DD command.

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Now the whole purpose of the DD command is really to copy and convert files as we see

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right here.

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Now this is very good for copying entire disks or partitions.

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So if you want to happen to maybe make a backup of a particular partition or a particular

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disk using the DD command is going to be a very good way to implement that solution.

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So let me quickly show you an example of doing such a thing.

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So what I'll do is I'll press Q.

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Okay, so if I do an LSBLK-F, now what I can see here are my block devices and one of

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these devices is SDB1, which I happen to use as a RAID member from a previous skill within

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this course.

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But it doesn't actually matter what the block device happens to be.

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Let's just say we wanted to copy the contents of this block device and back it up.

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We can do this using DD.

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So if I say sudo dd and I'll say if for the input file and I'll just specify devsdb1,

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this is what I want to copy.

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And then I'll say of for the output file ie, where do I want to copy it to?

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So I'll just say home IPv0 and I'll just call this file that I'm going to make a copy of.

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Now I can choose anything I wish, but I'll just say sdb1.ing to be nice and descriptive.

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And then I'll say my byte size.

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And the default value is 512.

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I'll make this a little bit bigger to speed up the process.

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I will say 8 meg.

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And I'll then say conf no error sync so that DD will ignore any errors if it happens to

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encounter them and continue on.

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So if I just hit enter now and type in my password, we can see here we've actually copied the

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entire contents of this particular disk.

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512 meg ie half a gig has been copied and we now have a bit by bit copy of this particular

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disk.

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And if we do an LS, we can see that copy is right here.

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Now as it transpires with respect to our input and our output, what I could do is I could

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copy directly from one disk and copy that to another disk, let's just maybe say we had

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sdc1, say for example.

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What this would ultimately do, it would create pretty much a carbon copy of whatever is on

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sdb1 and copy it directly onto the output file ie this disk right here.

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So if I happen to lose this disk, say for example it was destroyed, the content would

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still be available here within this particular file and I could use this file.

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So dd, I'll just say my input file happens to be home ipv0 and I'll use my sdb1 image

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and then I'll specify the output file, where do I actually want to copy it to and again

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I could copy this to anything I absolutely wish sdc1, whatever it may be, if that was

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a new fresh disk.

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But for now I'll just create another backup image, I'll call this sdb1 second copy dot

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img, gain, 8 meg and we will ignore any errors.

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If I hit enter, what we've done is create yet another backup copy of this image here,

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which is ultimately a copy of the content of this disk.

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So if you happen to have particular block devices, partitions, if you want to be able

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to create copies for backups, as we can see here the dd utility is going to allow you

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to do this no problem at all and you can ultimately copy from disks to create images, you can

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then use that image to copy directly back onto brand new disks, whatever it is you may

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choose the dd utility is going to help you out.

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Ok dogs so that is us for backing up our block devices, I hope this has been informative

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for you and I'd like to thank you for viewing.