1 00:00:07,230 --> 00:00:08,280 - [Instructor] One of the issues you might see is 2 00:00:08,280 --> 00:00:09,810 RAID is not found. 3 00:00:09,810 --> 00:00:10,740 Well, that's not good 4 00:00:10,740 --> 00:00:12,240 if you're booting to the RAID array. 5 00:00:12,240 --> 00:00:13,890 That means you can't boot to Windows, 6 00:00:13,890 --> 00:00:16,500 or whatever operating system you're using. 7 00:00:16,500 --> 00:00:18,240 So if the RAID array can't be found, 8 00:00:18,240 --> 00:00:19,650 you're gonna wanna check a couple things. 9 00:00:19,650 --> 00:00:24,650 First, you're gonna check the RAID array in the firmware. 10 00:00:25,020 --> 00:00:28,560 And that firmware could be in your UEFI or BIOS 11 00:00:28,560 --> 00:00:32,310 if your motherboard supports hardware-based RAID, 12 00:00:32,310 --> 00:00:34,710 or it could be a separate RAID adapter, 13 00:00:34,710 --> 00:00:37,140 like an Adaptec or a different card, 14 00:00:37,140 --> 00:00:38,790 that runs the connections 15 00:00:38,790 --> 00:00:41,523 and takes care of all the processing for that data. 16 00:00:42,870 --> 00:00:44,490 So you wanna access that firmware 17 00:00:44,490 --> 00:00:46,680 to see if the array is still functional. 18 00:00:46,680 --> 00:00:48,870 Now, if it's in the motherboard, 19 00:00:48,870 --> 00:00:52,020 well, you have to go into the motherboard BIOS or UEFI, 20 00:00:52,020 --> 00:00:56,100 you know, press F2 or Delete to get into that BIOS. 21 00:00:56,100 --> 00:00:57,660 If it's a RAID adapter, 22 00:00:57,660 --> 00:01:00,600 you might have to press a separate key like Control + I, 23 00:01:00,600 --> 00:01:01,590 or something, 24 00:01:01,590 --> 00:01:02,423 to get into that. 25 00:01:02,423 --> 00:01:05,640 And by the way, the RAID adapter card's firmware 26 00:01:05,640 --> 00:01:07,620 usually boots before, 27 00:01:07,620 --> 00:01:09,840 it usually shows up on the screen 28 00:01:09,840 --> 00:01:11,913 before the motherboard of BIOS. 29 00:01:12,900 --> 00:01:14,610 So keep that in mind 30 00:01:14,610 --> 00:01:17,340 and you might not have much time to actually catch that. 31 00:01:17,340 --> 00:01:20,970 But once you get into that firmware, wherever it's located, 32 00:01:20,970 --> 00:01:23,490 you wanna see if that array is still functional. 33 00:01:23,490 --> 00:01:24,990 So you wanna check those drives. 34 00:01:24,990 --> 00:01:28,353 It might be that the RAID 1 mirror is broken, 35 00:01:29,670 --> 00:01:31,650 and you have to replace one of the drives, 36 00:01:31,650 --> 00:01:35,820 and then copy the data back over to reestablish the mirror. 37 00:01:35,820 --> 00:01:38,580 It could be that the RAID 5 array has failed, 38 00:01:38,580 --> 00:01:43,380 because one drive has failed for whatever reason. 39 00:01:43,380 --> 00:01:45,900 And in that case, you'll have to replace that drive, 40 00:01:45,900 --> 00:01:49,650 and then rebuild the array from the parity data, 41 00:01:49,650 --> 00:01:51,630 or usually the better bet 42 00:01:51,630 --> 00:01:53,883 is to restore the data from backup. 43 00:01:54,840 --> 00:01:58,050 So here we'll show an example of a RAID array 44 00:01:58,050 --> 00:02:01,320 or just a RAID adapter that cannot be found. 45 00:02:01,320 --> 00:02:03,420 Here, I have one of my servers 46 00:02:03,420 --> 00:02:05,760 and it can run RAID 47 00:02:05,760 --> 00:02:07,080 but it's not right now. 48 00:02:07,080 --> 00:02:09,420 So we have to troubleshoot that. 49 00:02:09,420 --> 00:02:11,880 And so what I'm gonna do is go to Advanced, 50 00:02:11,880 --> 00:02:15,060 go down to SATA Configuration, 51 00:02:15,060 --> 00:02:16,380 and press Enter. 52 00:02:16,380 --> 00:02:20,850 Now, you'll see this setting here, SATA Mode Selection. 53 00:02:20,850 --> 00:02:23,790 The default is AHCI, 54 00:02:23,790 --> 00:02:24,750 which is what you use 55 00:02:24,750 --> 00:02:27,330 if you're just working with SATA drives 56 00:02:27,330 --> 00:02:31,770 in their regular state with no RAID at all. 57 00:02:31,770 --> 00:02:33,540 And so you can boot off for this drive, 58 00:02:33,540 --> 00:02:35,850 and you can see other drives, and so on. 59 00:02:35,850 --> 00:02:38,790 But if you want to use RAID 60 00:02:38,790 --> 00:02:42,210 and actually be able to access the RAID adapter 61 00:02:42,210 --> 00:02:44,403 and create RAID arrays, 62 00:02:45,300 --> 00:02:48,990 then you have to press Enter and change it to RAID 63 00:02:48,990 --> 00:02:50,940 that's for this particular motherboard. 64 00:02:50,940 --> 00:02:54,870 So different BIOS programs, different UEFI BIOS programs 65 00:02:54,870 --> 00:02:56,220 will have different settings 66 00:02:56,220 --> 00:02:58,470 and different navigation to that setting. 67 00:02:58,470 --> 00:03:02,550 This is just one example and it's just for SATA drives. 68 00:03:02,550 --> 00:03:04,890 But you may say, well, what happened here? 69 00:03:04,890 --> 00:03:06,990 Well, generally, you would set it to RAID 70 00:03:06,990 --> 00:03:08,970 and you would set up the RAID array. 71 00:03:08,970 --> 00:03:13,970 But let's say someone reset the BIOS to defaults, 72 00:03:14,700 --> 00:03:18,150 or they flashed the BIOS with an update, 73 00:03:18,150 --> 00:03:23,150 that might also set it to the default at AHCI. 74 00:03:23,550 --> 00:03:25,350 That's a default setting here. 75 00:03:25,350 --> 00:03:28,830 So then you just lose access to the RAID array. 76 00:03:28,830 --> 00:03:31,090 So we'd actually have to turn this on 77 00:03:32,730 --> 00:03:35,370 and save those settings in the BIOS. 78 00:03:35,370 --> 00:03:39,210 Then we could access the RAID utility. 79 00:03:39,210 --> 00:03:40,200 So we'll do that now. 80 00:03:40,200 --> 00:03:43,140 We'll do F4 to save and exit. 81 00:03:43,140 --> 00:03:43,973 Yes. 82 00:03:45,150 --> 00:03:47,400 That's gonna restart that server. 83 00:03:47,400 --> 00:03:48,233 And at some point, 84 00:03:48,233 --> 00:03:53,070 we'll get the option to access the Intel storage utility 85 00:03:53,070 --> 00:03:54,723 by pressing Control + I, 86 00:03:56,040 --> 00:03:59,010 and sometimes that's just after the initial BIOS, 87 00:03:59,010 --> 00:04:01,410 sometimes it's before the BIOS if you have a separate card. 88 00:04:01,410 --> 00:04:03,060 It depends. 89 00:04:03,060 --> 00:04:04,210 So we'll wait for that. 90 00:04:05,550 --> 00:04:06,383 Here we go. 91 00:04:06,383 --> 00:04:08,340 Control + I to enter the utility, 92 00:04:08,340 --> 00:04:09,813 gotta get in fast. 93 00:04:11,640 --> 00:04:12,870 And so here we are. 94 00:04:12,870 --> 00:04:14,490 We're into the RAID utility. 95 00:04:14,490 --> 00:04:18,300 Now you wouldn't even have that option to press Control + I 96 00:04:18,300 --> 00:04:22,050 to get into the Intel Rapid Storage Technology Enterprise 97 00:04:22,050 --> 00:04:23,610 RAID utility, 98 00:04:23,610 --> 00:04:25,950 if it was set to AHCI, 99 00:04:25,950 --> 00:04:28,020 you wouldn't have that ability at all. 100 00:04:28,020 --> 00:04:30,630 So first, you have to set it to RAID. 101 00:04:30,630 --> 00:04:32,370 Now, this is a double problem. 102 00:04:32,370 --> 00:04:34,860 This is two problems for the price of one, 103 00:04:34,860 --> 00:04:35,820 a double whammy. 104 00:04:35,820 --> 00:04:38,730 Not only was this reset 105 00:04:38,730 --> 00:04:40,680 and we couldn't even access RAID 106 00:04:40,680 --> 00:04:43,440 or get to the RAID utility, 107 00:04:43,440 --> 00:04:45,810 but we see there's a RAID 1 mirror here 108 00:04:45,810 --> 00:04:48,390 that has been degraded. 109 00:04:48,390 --> 00:04:50,100 That's a bad sign. 110 00:04:50,100 --> 00:04:53,070 That means that we don't have a RAID 1 mirror anymore. 111 00:04:53,070 --> 00:04:55,410 In fact, we only have one disk. 112 00:04:55,410 --> 00:04:57,330 That's a member disK here. 113 00:04:57,330 --> 00:05:01,500 and that's because I took out the other disk. 114 00:05:01,500 --> 00:05:03,510 I took out the other drive. 115 00:05:03,510 --> 00:05:06,690 It was indeed a RAID 1 mirror 116 00:05:06,690 --> 00:05:09,600 with two one-terabyte Western Digital drives, 117 00:05:09,600 --> 00:05:10,740 but I took that one out, 118 00:05:10,740 --> 00:05:12,720 so now it shows it as degraded. 119 00:05:12,720 --> 00:05:16,230 You might also see a message such as broken, 120 00:05:16,230 --> 00:05:17,490 or what have you. 121 00:05:17,490 --> 00:05:20,010 So this is where we'd go to reset that, 122 00:05:20,010 --> 00:05:20,843 but now we'd say, 123 00:05:20,843 --> 00:05:22,770 hey, it doesn't even see the other drive. 124 00:05:22,770 --> 00:05:24,960 So we'd have to figure out what the reason is for that. 125 00:05:24,960 --> 00:05:26,340 Maybe it got disconnected, 126 00:05:26,340 --> 00:05:28,230 maybe the drive was removed, 127 00:05:28,230 --> 00:05:31,860 maybe the SATA connectors just loose. 128 00:05:31,860 --> 00:05:33,870 So we'd have to get that connected, 129 00:05:33,870 --> 00:05:35,673 get that other drive in there, 130 00:05:36,600 --> 00:05:39,213 and then reestablish the mirror, 131 00:05:40,140 --> 00:05:43,233 and make sure that it is functional and established. 132 00:05:44,430 --> 00:05:48,423 So that's where you'd go to make those modifications. 133 00:05:49,830 --> 00:05:52,650 So, again, what we had here was we had a double error. 134 00:05:52,650 --> 00:05:53,970 We had a double issue. 135 00:05:53,970 --> 00:05:54,803 We had, 136 00:05:54,803 --> 00:05:56,640 the system couldn't even see RAID 137 00:05:56,640 --> 00:05:59,400 and couldn't even get into this RAID utility 138 00:05:59,400 --> 00:06:02,880 because the BIOS had either been reset, 139 00:06:02,880 --> 00:06:05,490 or changed, or set to defaults, 140 00:06:05,490 --> 00:06:07,230 or there was a flash update, 141 00:06:07,230 --> 00:06:11,370 and that RAID setting went back to its default, 142 00:06:11,370 --> 00:06:13,020 which was AHCI. 143 00:06:13,020 --> 00:06:14,850 Then the second problem, 144 00:06:14,850 --> 00:06:15,870 once we get in here, 145 00:06:15,870 --> 00:06:18,690 we see that the mirror has been degraded, 146 00:06:18,690 --> 00:06:20,700 'cause one of the disks is missing. 147 00:06:20,700 --> 00:06:23,610 This 120-gig drive, that's a non-RAID disk, 148 00:06:23,610 --> 00:06:26,250 that was never part of the mirror. 149 00:06:26,250 --> 00:06:27,840 But this one is 150 00:06:27,840 --> 00:06:29,220 and the other disk is missing. 151 00:06:29,220 --> 00:06:31,620 So you gotta figure out what the problem is with that. 152 00:06:31,620 --> 00:06:34,590 So that's one example of some RAID troubleshooting 153 00:06:34,590 --> 00:06:36,993 that you do on the hardware side. 154 00:06:39,450 --> 00:06:43,500 So here we have another image of another system 155 00:06:43,500 --> 00:06:46,950 where we have two Intel drives, 156 00:06:46,950 --> 00:06:49,170 each 120 gig, 157 00:06:49,170 --> 00:06:52,380 and you can see that it says non-RAID right now. 158 00:06:52,380 --> 00:06:55,233 We're in the Intel RAID utility, 159 00:06:56,100 --> 00:06:58,320 but there is no RAID volume. 160 00:06:58,320 --> 00:06:59,820 None are defined right now. 161 00:06:59,820 --> 00:07:02,730 So that's another thing you might see, 162 00:07:02,730 --> 00:07:06,660 where for some reason the RAID volume is missing 163 00:07:06,660 --> 00:07:09,150 and you'd see non-RAID disk, 164 00:07:09,150 --> 00:07:11,700 so for both drives, 165 00:07:11,700 --> 00:07:12,600 which are, 166 00:07:12,600 --> 00:07:15,570 you know, they are identical drives 167 00:07:15,570 --> 00:07:19,650 that look like they should be part of a RAID 1 mirror. 168 00:07:19,650 --> 00:07:21,033 So that's something else. 169 00:07:22,590 --> 00:07:25,260 And excuse the image here, 170 00:07:25,260 --> 00:07:28,470 but this is a real image of a data mirror, 171 00:07:28,470 --> 00:07:31,293 using the same type of utility, RAID 1, 172 00:07:32,430 --> 00:07:35,310 750 gigs was used for this, 173 00:07:35,310 --> 00:07:37,020 and the status is normal. 174 00:07:37,020 --> 00:07:38,550 That's what you wanna see here. 175 00:07:38,550 --> 00:07:41,403 And we see we have the two member disks here. 176 00:07:42,960 --> 00:07:44,880 So two one-terabyte drives, 177 00:07:44,880 --> 00:07:47,490 but we're only using 750 gig 178 00:07:47,490 --> 00:07:51,330 of that one terabyte for this RAID 1 mirror, 179 00:07:51,330 --> 00:07:53,130 and status is normal. 180 00:07:53,130 --> 00:07:54,480 So that's an example. 181 00:07:54,480 --> 00:07:57,120 Now this is all hardware-based stuff that I'm showing. 182 00:07:57,120 --> 00:07:58,740 And that's the way to go. 183 00:07:58,740 --> 00:08:02,220 Generally, you don't want to go with software-based RAID. 184 00:08:02,220 --> 00:08:05,190 You want to go with something that is firmware-controlled 185 00:08:05,190 --> 00:08:07,620 and outside of the operating system 186 00:08:07,620 --> 00:08:10,830 that you're using like Windows or Linux. 187 00:08:10,830 --> 00:08:15,423 So remember, the best way to run RAID is hardware-based. 188 00:08:17,250 --> 00:08:21,240 And before we continue with some of the issues, 189 00:08:21,240 --> 00:08:25,890 you definitely wanna remember your RAID levels, 190 00:08:25,890 --> 00:08:28,740 especially RAID 1, mirroring, 191 00:08:28,740 --> 00:08:30,280 where you have two drives 192 00:08:31,290 --> 00:08:33,090 that are connected to one controller, 193 00:08:33,090 --> 00:08:33,923 identical drives, 194 00:08:33,923 --> 00:08:36,840 and the data is mirrored to both drives, 195 00:08:36,840 --> 00:08:39,030 and then, also RAID 5, 196 00:08:39,030 --> 00:08:40,503 striping with parity, 197 00:08:42,600 --> 00:08:45,240 where the data is striped across, 198 00:08:45,240 --> 00:08:48,243 and the parity information is striped across as well, 199 00:08:50,760 --> 00:08:55,530 and RAID 10 which combines RAID 1 mirroring 200 00:08:55,530 --> 00:08:57,873 with regular striping without parity. 201 00:09:00,420 --> 00:09:02,760 And you might wanna remember MTBF, 202 00:09:02,760 --> 00:09:05,910 mean time between failures. 203 00:09:05,910 --> 00:09:08,460 And you wanna be able to define 204 00:09:08,460 --> 00:09:10,470 how many failures per million, 205 00:09:10,470 --> 00:09:13,920 or mean time between failures for your RAID arrays. 206 00:09:13,920 --> 00:09:16,740 But definitely know your RAID levels. 207 00:09:16,740 --> 00:09:18,330 That's a little review right there, 208 00:09:18,330 --> 00:09:21,420 but let's get back into some of the issues 209 00:09:21,420 --> 00:09:22,413 that you might see. 210 00:09:24,180 --> 00:09:26,010 But you also wanna check the physical connections 211 00:09:26,010 --> 00:09:27,030 of the drives 212 00:09:27,030 --> 00:09:30,000 to the RAID card or to the motherboard, 213 00:09:30,000 --> 00:09:31,470 make sure that everything is secure, 214 00:09:31,470 --> 00:09:34,860 verify the data connection and the power connection, 215 00:09:34,860 --> 00:09:38,130 'cause either could cause a RAID failure. 216 00:09:38,130 --> 00:09:40,890 So if the RAID array cannot be found, 217 00:09:40,890 --> 00:09:42,990 make sure that you check all the connections, 218 00:09:42,990 --> 00:09:46,800 make sure that you check the array in the firmware. 219 00:09:46,800 --> 00:09:49,380 And the other possibility is RAID just stops working. 220 00:09:49,380 --> 00:09:50,640 And it might stop working 221 00:09:50,640 --> 00:09:52,470 and you can't get into the operating system 222 00:09:52,470 --> 00:09:54,600 if you're booting from a RAID array, 223 00:09:54,600 --> 00:09:57,450 or it could be that you're storing data on the array 224 00:09:57,450 --> 00:10:00,900 and it suddenly stops working as you're working in Windows. 225 00:10:00,900 --> 00:10:03,810 So you're gonna wanna view the array of drives 226 00:10:03,810 --> 00:10:05,550 in Disk Management 227 00:10:05,550 --> 00:10:09,150 and see, first of all, if the array is working properly 228 00:10:09,150 --> 00:10:10,830 if you're running it in Windows, 229 00:10:10,830 --> 00:10:13,740 otherwise, it'll just show up as one volume letter 230 00:10:13,740 --> 00:10:14,940 in Disk Management, 231 00:10:14,940 --> 00:10:17,090 and you wanna see if that's healthy or not. 232 00:10:18,930 --> 00:10:22,020 Then, take it further and access the firmware 233 00:10:22,020 --> 00:10:23,733 and analyze each drive. 234 00:10:24,750 --> 00:10:27,240 You might be able to save drives as well 235 00:10:27,240 --> 00:10:28,770 and you might be able to do that 236 00:10:28,770 --> 00:10:33,030 with the sfc command, or the chkdsk command, 237 00:10:33,030 --> 00:10:34,710 or third party tools. 238 00:10:34,710 --> 00:10:38,040 So you're gonna wanna try to save the drive, if possible. 239 00:10:38,040 --> 00:10:40,860 But if not, you're gonna need to rebuild the array, 240 00:10:40,860 --> 00:10:43,890 and most likely restore the data from your backup. 241 00:10:43,890 --> 00:10:45,780 So a couple other things to check. 242 00:10:45,780 --> 00:10:49,350 You wanna check if it was a single drive failure 243 00:10:49,350 --> 00:10:52,443 or if the failure was multiple drives. 244 00:10:53,580 --> 00:10:55,110 Because that can be very telling. 245 00:10:55,110 --> 00:10:57,120 A single drive failure that happens, 246 00:10:57,120 --> 00:10:58,200 hard drives will fail. 247 00:10:58,200 --> 00:10:59,880 It's just a matter of time. 248 00:10:59,880 --> 00:11:02,490 But if multiple drives failed at the same time, 249 00:11:02,490 --> 00:11:04,290 it could be a configuration problem, 250 00:11:04,290 --> 00:11:07,110 a connection problem, or a power issue. 251 00:11:07,110 --> 00:11:09,600 So you want to identify first 252 00:11:09,600 --> 00:11:10,980 whether it's a single drive failure 253 00:11:10,980 --> 00:11:12,930 or multiple drive failure. 254 00:11:12,930 --> 00:11:16,230 Then you wanna look into whether it's a controller failure, 255 00:11:16,230 --> 00:11:18,990 maybe the RAID card failed, 256 00:11:18,990 --> 00:11:23,040 maybe the firmware portion for the motherboard failed, 257 00:11:23,040 --> 00:11:24,810 or maybe the motherboard needs an update, 258 00:11:24,810 --> 00:11:26,670 maybe there was a short. 259 00:11:26,670 --> 00:11:28,710 Check for a controller failure 260 00:11:28,710 --> 00:11:30,840 and consider using duplexing, 261 00:11:30,840 --> 00:11:34,293 two controllers in a RAID 1 mirroring environment. 262 00:11:35,250 --> 00:11:37,110 You can check for power surges 263 00:11:37,110 --> 00:11:39,570 and subsequent RAID failures. 264 00:11:39,570 --> 00:11:40,890 Power surges might happen. 265 00:11:40,890 --> 00:11:42,590 You wanna make sure that your system's connected 266 00:11:42,590 --> 00:11:45,420 to a good surge suppressor, 267 00:11:45,420 --> 00:11:47,973 or line conditioner, or UPS. 268 00:11:49,350 --> 00:11:52,950 And you can also check for improper rebuilds of the array. 269 00:11:52,950 --> 00:11:54,990 Another person, another technician 270 00:11:54,990 --> 00:11:57,840 might have rebuilt the array incorrectly. 271 00:11:57,840 --> 00:11:59,970 So watch out for that as well. 272 00:11:59,970 --> 00:12:02,370 And then, finally, software issues. 273 00:12:02,370 --> 00:12:06,120 Watch for configuration errors, viruses, 274 00:12:06,120 --> 00:12:10,680 or unauthorized deletion of a array, and so on. 275 00:12:10,680 --> 00:12:12,090 It could be a user error, 276 00:12:12,090 --> 00:12:12,990 it could be a virus, 277 00:12:12,990 --> 00:12:15,600 it could be malware configuration problem. 278 00:12:15,600 --> 00:12:17,040 So check all these things. 279 00:12:17,040 --> 00:12:17,940 Think of all these things 280 00:12:17,940 --> 00:12:20,100 as you're working with these errors 281 00:12:20,100 --> 00:12:23,940 of RAID not found and RAID stops working. 282 00:12:23,940 --> 00:12:27,150 Those two things can eat up a lot of your time. 283 00:12:27,150 --> 00:12:30,420 So there's a lot of stuff to look at for you 284 00:12:30,420 --> 00:12:32,340 and help you troubleshoot a little bit. 285 00:12:32,340 --> 00:12:33,990 And that's it for the sub-lesson.