1 00:00:00,000 --> 00:00:16,920 Hey guys and welcome back. So now what I'm going to do is I'm going to walk you through 2 00:00:16,920 --> 00:00:21,960 a basic setup of using software RAID on our Linux machine. So what I'm first going to 3 00:00:21,960 --> 00:00:26,640 do is I'm going to add two new disks to my machine right now. So what I will do is I'll 4 00:00:26,640 --> 00:00:32,719 click my device, I'll go to settings, I will go to storage and I already have a second 5 00:00:32,719 --> 00:00:38,159 disk but I'll just add another so go down to here and click this little icon and then 6 00:00:38,159 --> 00:00:43,200 choose hard disk. Now I'll create a disk, I'll just say next, next and I'll make the 7 00:00:43,200 --> 00:00:48,040 size pretty small, I'll just maybe make it around half a gig maybe, let's create you 8 00:00:48,040 --> 00:00:53,719 and I'll scroll down, select it and click choose. So now that has been added, what I'll 9 00:00:53,719 --> 00:00:59,039 now do is do the same thing once again, just add another, I'll create again, just make 10 00:00:59,039 --> 00:01:04,400 one of the same size and I'll just choose this. Okay, perfect. So I'll say okay and 11 00:01:04,400 --> 00:01:09,359 now I'll start my machine up with these two new disks added. Okay, so I have logged back 12 00:01:09,359 --> 00:01:16,799 into my machine. If I do an LS on my dev SD drives and I do well card, we can actually 13 00:01:16,799 --> 00:01:23,560 see we've added these two new devices SDC and SDD, neither of which have been partitioned 14 00:01:23,560 --> 00:01:28,280 though. Now one particular file location that we absolutely want to be remembering that 15 00:01:28,280 --> 00:01:34,400 we can use to verify that a RAID device has been created is by looking at the contents 16 00:01:34,400 --> 00:01:42,280 of the proc MD stat file. This file MD stat stands for multiple disks, so MD stat multiple 17 00:01:42,280 --> 00:01:49,560 disk statistics. If I say cat proc MD stat, notice here that right now we have no information 18 00:01:49,560 --> 00:01:54,359 here, meaning that we do not have any RAID devices. What I'm now going to do is I'm going 19 00:01:54,359 --> 00:02:00,320 to use F disk to partition those new drives I just added. So what I'll do is I'll say 20 00:02:00,320 --> 00:02:07,159 pseudo F disk and the first device is going to be SDC. So I'll hit enter, I will say N 21 00:02:07,159 --> 00:02:11,920 to create a new partition, I will say P for the primary partition, partition number will 22 00:02:11,920 --> 00:02:18,439 be one and I'll just hit enter, enter for my default sectors. Now one thing to note here 23 00:02:18,439 --> 00:02:24,280 is that it says here it's created one partition of type Linux. Now remember what we talked 24 00:02:24,280 --> 00:02:30,560 about in the previous nugget, there is actually a particular label we want to give this partition 25 00:02:30,560 --> 00:02:35,280 to denote it that it is a RAID partition. So if we want to change the type, what I can 26 00:02:35,280 --> 00:02:41,240 do is say T to change the type and I want to list the actual hex codes, so I'll do capital 27 00:02:41,240 --> 00:02:47,079 L and this will show me all my different codes. Now the one I want to do is this one right 28 00:02:47,080 --> 00:02:53,640 here FD which is a Linux RAID auto partition. This will give it that FD marking we were 29 00:02:53,640 --> 00:02:59,320 talking about. So now I will say FD and it's now changing the partition type from a regular 30 00:02:59,320 --> 00:03:05,480 Linux that we would use for a regular partition to a Linux RAID auto detect partition. Now 31 00:03:05,480 --> 00:03:11,520 that I've done this, I will say W to write that information and now that has been written 32 00:03:11,520 --> 00:03:17,640 to and saved. So we want to do the same thing but we want to do it for SDD this time. So 33 00:03:17,640 --> 00:03:23,320 we'll do the same, we'll create a new partition, make it a primary partition, number one default 34 00:03:23,320 --> 00:03:28,520 sectors. The type is going to be as we can see here Linux, we have to change that so 35 00:03:28,520 --> 00:03:33,920 we'll say T again, check the code, it's going to be FD. That is now being changed, we'll 36 00:03:33,920 --> 00:03:40,760 say W to write and that has also been written to. Now if we happen to cat our proc MD stat 37 00:03:40,759 --> 00:03:46,039 file, notice that nothing has actually changed quite just yet. We still have to use some 38 00:03:46,039 --> 00:03:51,439 particular commands to create these RAID partitions. Now the command that we want to be using is 39 00:03:51,439 --> 00:03:58,439 one called MDADM. This is the multiple disks admin tool. So like I say right now, if I 40 00:03:58,439 --> 00:04:05,519 go into my dev directory and just list everything, we can see these new devices with new partition 41 00:04:05,520 --> 00:04:12,920 SDD1, SDC1 but notice there is not one called MD0 quite just yet. This is one we're actually 42 00:04:12,920 --> 00:04:18,300 going to create and we'll do so using the MDADM command. So if I clear the screen and I say 43 00:04:18,300 --> 00:04:24,639 man MDADM. Oh, we do not have this. This is because I have forgotten to install it. So 44 00:04:24,639 --> 00:04:31,120 I'll have to install MDADM. There we go. And I'll say yes. That will go through the installation. 45 00:04:31,240 --> 00:04:37,319 Okay, so let's try that man page one more time. Now it does appear. So we can see this tool 46 00:04:37,319 --> 00:04:43,639 here, this utility is to manage Linux software RAID and we can get our big description about 47 00:04:43,639 --> 00:04:48,160 all this information. But if we scroll on down, we can see the different options we have available 48 00:04:48,160 --> 00:04:53,519 to us. We can do the dash capital C or dash dash create to create a new array. This is 49 00:04:53,519 --> 00:04:58,079 something we definitely want to be doing. Now another important thing we want to specify 50 00:04:58,159 --> 00:05:04,319 here, we can also do dash V or dash dash verbose so that we can actually print out what is 51 00:05:04,319 --> 00:05:10,039 happening as the array is being created. A very, very important one is this one here dash L or 52 00:05:10,039 --> 00:05:17,279 dash dash level. This is the option that we can use to specify the RAID level we want to invoke. 53 00:05:17,279 --> 00:05:23,000 So remember in the previous nugget, we said we could have things like RAID 0 or RAID 1 or RAID 10, 54 00:05:23,079 --> 00:05:29,079 RAID 5. There actually are even more RAID levels which we can see here RAID 4, for example. But 55 00:05:29,079 --> 00:05:34,680 for the purposes of the examination, 0, 1, 5 and 10 are the main ones that we want to focus on. 56 00:05:34,680 --> 00:05:41,079 So with this option, we can specify a particular array that we want to invoke. Let's say I want 57 00:05:41,079 --> 00:05:47,959 to invoke a mirrored array. So we have perfect redundancy, i.e. each disk has a carbon copy 58 00:05:47,959 --> 00:05:54,439 of the data. We can use RAID level 1. So that is what we will do right now if I press Q here 59 00:05:54,439 --> 00:06:01,079 and I clear my screen. What I'll do is I'll say MDADM. In fact, I will use my SuperUser privileges. 60 00:06:01,079 --> 00:06:06,679 I'll say MDADM and I will say dash dash create or I could do dash C as we saw and I'll say 61 00:06:07,240 --> 00:06:13,240 dash dash verbose so we can see the outputs. And now what I want to do is I want to specify 62 00:06:13,240 --> 00:06:20,199 the name of the array, the partition that we want to create. So I'll say in dev, we'll have one called 63 00:06:20,199 --> 00:06:27,319 MD0. So multiple disk 0. 0 being the very first one we create. If we create another one, we could 64 00:06:27,319 --> 00:06:34,600 call it MD1 and then another one MD2 so on and so forth. So we will say MD0 and now I want to specify 65 00:06:34,600 --> 00:06:41,639 the level that we want to create. We want RAID 1 and now what I have to specify are what devices 66 00:06:41,719 --> 00:06:47,479 am I going to use within this RAID array? So I will say RAID devices equals 2 because we have 67 00:06:47,479 --> 00:06:53,079 two disks that we want to use. And now I'm going to supply as an argument these different disks. So 68 00:06:53,079 --> 00:07:01,000 we had SDC1 which was the partition we just created for the new disk as well as the other disk which 69 00:07:01,000 --> 00:07:08,680 was SDD1. Both of these partitions remember have been marked with that FD label. So I will hit 70 00:07:08,680 --> 00:07:15,400 ENTER. I will say yes, hit ENTER again and now the array has been created. So what I can do now is I 71 00:07:15,400 --> 00:07:23,000 can do LS and my dev directory. Notice now we have MD0 right here. Now what we can do here is treat 72 00:07:23,000 --> 00:07:29,319 this like a regular partition. So what we'll do is we'll use FDIS on dev MD0. I'll create a new 73 00:07:29,319 --> 00:07:35,800 partition. I'll make a primary partition. I'll hit ENTER and ENTER and ENTER. The partition type, 74 00:07:35,879 --> 00:07:42,360 this one is interesting. This time we're just going to leave it as the regular Linux because 75 00:07:42,360 --> 00:07:47,240 ultimately it's just going to store regular Linux information. So that is why we're just going to 76 00:07:47,240 --> 00:07:54,360 leave that. If I hit W, this is now going to be written to, if I want to add a file system, 77 00:07:54,360 --> 00:08:00,280 we can do that with the commands we have saw before, MKFS. So I will say sudo MKFS. So I'll 78 00:08:00,279 --> 00:08:09,399 clear the screen. I'll say sudo MKFS EXT4 and we'll do it on dev MD0. I'll say yes. And now if I 79 00:08:09,399 --> 00:08:17,399 cat proc MDSTAT, we can see here we now actually have a RAID1 array and we can see what is actually 80 00:08:17,399 --> 00:08:25,399 active within this array. We have SDD1 and SDC1, the two partitions of the two different disks 81 00:08:25,399 --> 00:08:31,639 that we just added. Notice here we have this value uu. This denotes those physical disks, 82 00:08:31,639 --> 00:08:36,199 both of which are in the upstate. If one of those were broken, we would actually see a 83 00:08:36,199 --> 00:08:42,600 dot here instead of the actual u. So right now we have an active RAID array. This is very, very good. 84 00:08:42,600 --> 00:08:49,079 Now, here as a deal, if we happen to reboot our system, this RAID device is going to exist, but it 85 00:08:49,160 --> 00:08:55,800 will not be active any longer. The reboot will effectively deactivate it. Now you can just use 86 00:08:55,800 --> 00:09:02,120 the MDADM command to manually activate the RAID device every time you have a new boot, because 87 00:09:02,120 --> 00:09:08,280 like I say, it will boot up in an active state. But what you can do is you can create a configuration 88 00:09:08,280 --> 00:09:17,080 file for MDADM. So what I'll do here is I'll say MDADM-DETAIL-SCAN. Oh, and of course I need my 89 00:09:17,160 --> 00:09:25,240 super user privileges, so MDADM-DETAIL-SCAN. And this information here, we want to populate this 90 00:09:25,240 --> 00:09:31,960 information into the MDADM configuration file. So what I will do here is I'll actually just take 91 00:09:31,960 --> 00:09:41,800 this output and I'll redirect it into Etsy, mdadm.conf. Now try to remember that particular location. 92 00:09:41,879 --> 00:09:48,279 This is where we can store our configurations for MDADM-related configs, because ultimately, 93 00:09:48,279 --> 00:09:53,959 once we pipe in this information here that we're seeing into this configuration file, 94 00:09:53,959 --> 00:10:00,039 this is going to allow us to automatically enable the RAID device and activate it when it has been 95 00:10:00,039 --> 00:10:05,399 rebooted. So if I hit Enter now, oh, and in fact, you know what, I should actually just change to my 96 00:10:05,399 --> 00:10:11,479 root because I have to write into my Etsy directory. So I'll just change to the root user and I'll just 97 00:10:11,480 --> 00:10:17,560 do that instead. So MDADM, that's a good little point to make aware of and pipe it into Etsy, 98 00:10:17,560 --> 00:10:25,320 mdadm.conf. If I hit Enter now and I go into this particular file, let me just use nano instead, 99 00:10:25,320 --> 00:10:31,159 this file is now populated with this information. And like I say, that will automatically activate 100 00:10:31,159 --> 00:10:36,519 and enable the RAID device even when you reboot it as opposed to having to manually issue the command 101 00:10:36,519 --> 00:10:42,679 every time the system has a new reboot. So we can now survive reboots. What we now want to be able 102 00:10:42,679 --> 00:10:48,679 to do is we would want to be able to mount this particular drive. So if we want to be able to 103 00:10:48,679 --> 00:10:53,480 create a mount point, what we will do is we will make a directory, let's just call it, I don't know, 104 00:10:53,480 --> 00:11:01,159 forward slash RAID perhaps. If I go to the root directory, do an LS, we now have this RAID directory. 105 00:11:01,159 --> 00:11:07,399 Now, can you remember the location of the file that we use in order to have persistent mounting 106 00:11:07,399 --> 00:11:12,919 of our file systems? If you said the Etsy FS tab file, that is absolutely correct. So that's the 107 00:11:12,919 --> 00:11:18,360 one we're going to modify. We're going to Etsy FS tab. And I'm just going to add this information 108 00:11:18,360 --> 00:11:25,159 right here. So what is the device I want to add? I want to add MD0. What is the location of the 109 00:11:25,159 --> 00:11:31,879 mount point? I will just say forward slash RAID. What is the file system type? It'll be EXT4. 110 00:11:31,879 --> 00:11:37,240 The options, I'll just give it the defaults. I'll have the dump value at zero and I'll make the 111 00:11:37,240 --> 00:11:43,639 past value priority three. So if I save this and exit out, I can now get this. This is now being 112 00:11:43,639 --> 00:11:50,279 updated. I can use my mount dash a command, which will mount everything that I have specified within 113 00:11:50,279 --> 00:11:57,480 the FS tab file. So now if I happen to say mounts and I grep for RAIDs, we can actually now see 114 00:11:57,480 --> 00:12:03,959 that this file system has been mounted and it is indeed a RAID array. If I do an LSBLK-F, 115 00:12:03,959 --> 00:12:13,399 we can also see this here. SDD, this is a Linux RAID member, as is SDC also a Linux RAID member. 116 00:12:13,399 --> 00:12:21,240 We can see the label, the label, notice the UUID here is absolutely identical here and absolutely 117 00:12:21,240 --> 00:12:28,360 identical down here. And we can see the mount point is at forward slash RAID and forward slash RAID. 118 00:12:28,360 --> 00:12:34,519 So really we saw here with the MDADM command, we can easily create a RAID array. We also understand 119 00:12:34,519 --> 00:12:40,919 we can find information relating to our multiple disk statistics with respect to a RAID array in 120 00:12:40,919 --> 00:12:46,839 the PROC directory with the MDSTAT command. This will show that we have an active RAID array. 121 00:12:46,839 --> 00:12:52,279 If we want our RAID array to be active after each reboot, we want to create a configuration file which 122 00:12:52,279 --> 00:12:58,519 can automate that process. And if we want our devices or our drives to be automatically mounted, 123 00:12:58,519 --> 00:13:05,639 we want to make an addition or an amendment to our SAFS tab file. Okay, so that is us for our 124 00:13:05,639 --> 00:13:10,279 introduction into our basic RAID configuration tools. I hope this has been informative for you 125 00:13:10,279 --> 00:13:14,279 and I'd like to thank you for viewing.