What is the lethality of a SMART error?
We have a 40 TB storage server in RAID 5, with twelve 2 TB drives. One drive is acting as a hotspare, and it's being managed with a hardware RAID controller.
For some forsaken reason, three drives apparently failed simultaneously. One appears to have failed entirely, while two are showing SMART errors. The hotspare does not appear to have been converted into part of the array, but I am not sure if that would have happened automatically anyways.
The question is, is it possible to restart those two drives, rebuild the array, and then save that data before those drives ultimately fail? My knowledge of the SMART error is that it is not an outright failure, but merely a predicted failure.
Obviously these drives need to be replaced shortly, but are they totally bust or can they be saved?
hard-drive raid storage hardware-raid
add a comment |
We have a 40 TB storage server in RAID 5, with twelve 2 TB drives. One drive is acting as a hotspare, and it's being managed with a hardware RAID controller.
For some forsaken reason, three drives apparently failed simultaneously. One appears to have failed entirely, while two are showing SMART errors. The hotspare does not appear to have been converted into part of the array, but I am not sure if that would have happened automatically anyways.
The question is, is it possible to restart those two drives, rebuild the array, and then save that data before those drives ultimately fail? My knowledge of the SMART error is that it is not an outright failure, but merely a predicted failure.
Obviously these drives need to be replaced shortly, but are they totally bust or can they be saved?
hard-drive raid storage hardware-raid
add a comment |
We have a 40 TB storage server in RAID 5, with twelve 2 TB drives. One drive is acting as a hotspare, and it's being managed with a hardware RAID controller.
For some forsaken reason, three drives apparently failed simultaneously. One appears to have failed entirely, while two are showing SMART errors. The hotspare does not appear to have been converted into part of the array, but I am not sure if that would have happened automatically anyways.
The question is, is it possible to restart those two drives, rebuild the array, and then save that data before those drives ultimately fail? My knowledge of the SMART error is that it is not an outright failure, but merely a predicted failure.
Obviously these drives need to be replaced shortly, but are they totally bust or can they be saved?
hard-drive raid storage hardware-raid
We have a 40 TB storage server in RAID 5, with twelve 2 TB drives. One drive is acting as a hotspare, and it's being managed with a hardware RAID controller.
For some forsaken reason, three drives apparently failed simultaneously. One appears to have failed entirely, while two are showing SMART errors. The hotspare does not appear to have been converted into part of the array, but I am not sure if that would have happened automatically anyways.
The question is, is it possible to restart those two drives, rebuild the array, and then save that data before those drives ultimately fail? My knowledge of the SMART error is that it is not an outright failure, but merely a predicted failure.
Obviously these drives need to be replaced shortly, but are they totally bust or can they be saved?
hard-drive raid storage hardware-raid
hard-drive raid storage hardware-raid
asked Dec 3 at 19:06
Taylor F
82
82
add a comment |
add a comment |
2 Answers
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The one outright-failed drive should be replaced ASAP, and the array can rebuild itself. The drives should SMART failures are more likely to fail than ones not showing SMART failures, according to this study : https://static.googleusercontent.com/media/research.google.com/en//archive/disk_failures.pdf . They should also be replaced, and never used in important use cases again.
Assuming that you are using identical hard drives, it's worth getting multiple spares, the number depending on how long you expect the storage device to remain in service.
In my opinion, RAID5 is not a good option for arrays of drives larger than 1 TB. RAID5 takes a long time to rebuild and performance is slow while rebuilding. RAID5 is also not very helpful when you have many (12) disks in an array, because it only protects against one failure. A second failure ruins the whole array.
For future builds, I suggest using RAID10 instead, it will give more consistent fast performance while providing better failure tolerance.
Yeah, thanks for the points. As is usually the case, I wasn't the one to set it up, just the one to try and fix it! I mentioned in the above comment, the array does not seem to rebuild, potentially because it's now listed as a foreign array on our Dell PERC controller. When we try to import, we can't because there are still failed (the SMART drives) drives in the array. Any thoughts on forcing it to rebuild?
– Taylor F
Dec 3 at 19:58
I haven't used Dell PERC controllers, unfortunately. Dell Support may be a better resource for you, if you can queue up a bunch of tasks to do while waiting on the phone :( . If the data on the device was backed up, it's worth figuring out the steps to restore.
– Christopher Hostage
Dec 3 at 21:01
:( indeed. Hurts when Dell Support is the next best option. Going to try and find some hardware documentation and try to parse that. Thanks for the help.
– Taylor F
Dec 3 at 21:24
add a comment |
It is my understanding that RAID 5 allows for 1 disk failure in the array. The hotspare is built accordingly when requested. The controller/GUI or whatever front end you are using is used to do this. The time taken rebuilding the RAID is dependant on the amount of data in use. Once the hotspare is built your RAID will in theory be back to normal. In this time take one of the other drives with the SMART errors offline and rebuild it using the hotspare process. Complete until all your HDD with errors are replaced. I would replace any disk with critical data on it showing SMART errors. You could use RAID 6 going forward, of course you would have to back up all your data by moving it, rebuild the array and put it back. RAID 6 allows for more disk failures but you do take a small hit on the write speed.
Yeah this has obviously been a wake up call as to the trouble of this set up. It sounds like this process should be automatic? We did replace the failed drive and it does not appear to perform any changes to the setup. The server is using a Dell PERC, and the configuration is now listed under "foreign config." With the failed drives, it can't be loaded back into the the active configuration setting. Any thoughts on getting that to work?
– Taylor F
Dec 3 at 19:55
I just read my comment and laughed at the fact it's called a "hotspare" for a reason.. Sorry. I have used dell perc and I remember on building the raid you select the disk to use as the hotspare so should any disk fail it takes over and then a red light comes on your faulty hdd. This is the drive you replace and then that becomes the hot spare. It's all come flooding back now. My advice would be back that up ASAP and get dell support. If you don't have it, rebuild your raid ASAP on new hardware with backup. You risk losing it mate.
– jpsaunders
Dec 4 at 23:13
add a comment |
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The one outright-failed drive should be replaced ASAP, and the array can rebuild itself. The drives should SMART failures are more likely to fail than ones not showing SMART failures, according to this study : https://static.googleusercontent.com/media/research.google.com/en//archive/disk_failures.pdf . They should also be replaced, and never used in important use cases again.
Assuming that you are using identical hard drives, it's worth getting multiple spares, the number depending on how long you expect the storage device to remain in service.
In my opinion, RAID5 is not a good option for arrays of drives larger than 1 TB. RAID5 takes a long time to rebuild and performance is slow while rebuilding. RAID5 is also not very helpful when you have many (12) disks in an array, because it only protects against one failure. A second failure ruins the whole array.
For future builds, I suggest using RAID10 instead, it will give more consistent fast performance while providing better failure tolerance.
Yeah, thanks for the points. As is usually the case, I wasn't the one to set it up, just the one to try and fix it! I mentioned in the above comment, the array does not seem to rebuild, potentially because it's now listed as a foreign array on our Dell PERC controller. When we try to import, we can't because there are still failed (the SMART drives) drives in the array. Any thoughts on forcing it to rebuild?
– Taylor F
Dec 3 at 19:58
I haven't used Dell PERC controllers, unfortunately. Dell Support may be a better resource for you, if you can queue up a bunch of tasks to do while waiting on the phone :( . If the data on the device was backed up, it's worth figuring out the steps to restore.
– Christopher Hostage
Dec 3 at 21:01
:( indeed. Hurts when Dell Support is the next best option. Going to try and find some hardware documentation and try to parse that. Thanks for the help.
– Taylor F
Dec 3 at 21:24
add a comment |
The one outright-failed drive should be replaced ASAP, and the array can rebuild itself. The drives should SMART failures are more likely to fail than ones not showing SMART failures, according to this study : https://static.googleusercontent.com/media/research.google.com/en//archive/disk_failures.pdf . They should also be replaced, and never used in important use cases again.
Assuming that you are using identical hard drives, it's worth getting multiple spares, the number depending on how long you expect the storage device to remain in service.
In my opinion, RAID5 is not a good option for arrays of drives larger than 1 TB. RAID5 takes a long time to rebuild and performance is slow while rebuilding. RAID5 is also not very helpful when you have many (12) disks in an array, because it only protects against one failure. A second failure ruins the whole array.
For future builds, I suggest using RAID10 instead, it will give more consistent fast performance while providing better failure tolerance.
Yeah, thanks for the points. As is usually the case, I wasn't the one to set it up, just the one to try and fix it! I mentioned in the above comment, the array does not seem to rebuild, potentially because it's now listed as a foreign array on our Dell PERC controller. When we try to import, we can't because there are still failed (the SMART drives) drives in the array. Any thoughts on forcing it to rebuild?
– Taylor F
Dec 3 at 19:58
I haven't used Dell PERC controllers, unfortunately. Dell Support may be a better resource for you, if you can queue up a bunch of tasks to do while waiting on the phone :( . If the data on the device was backed up, it's worth figuring out the steps to restore.
– Christopher Hostage
Dec 3 at 21:01
:( indeed. Hurts when Dell Support is the next best option. Going to try and find some hardware documentation and try to parse that. Thanks for the help.
– Taylor F
Dec 3 at 21:24
add a comment |
The one outright-failed drive should be replaced ASAP, and the array can rebuild itself. The drives should SMART failures are more likely to fail than ones not showing SMART failures, according to this study : https://static.googleusercontent.com/media/research.google.com/en//archive/disk_failures.pdf . They should also be replaced, and never used in important use cases again.
Assuming that you are using identical hard drives, it's worth getting multiple spares, the number depending on how long you expect the storage device to remain in service.
In my opinion, RAID5 is not a good option for arrays of drives larger than 1 TB. RAID5 takes a long time to rebuild and performance is slow while rebuilding. RAID5 is also not very helpful when you have many (12) disks in an array, because it only protects against one failure. A second failure ruins the whole array.
For future builds, I suggest using RAID10 instead, it will give more consistent fast performance while providing better failure tolerance.
The one outright-failed drive should be replaced ASAP, and the array can rebuild itself. The drives should SMART failures are more likely to fail than ones not showing SMART failures, according to this study : https://static.googleusercontent.com/media/research.google.com/en//archive/disk_failures.pdf . They should also be replaced, and never used in important use cases again.
Assuming that you are using identical hard drives, it's worth getting multiple spares, the number depending on how long you expect the storage device to remain in service.
In my opinion, RAID5 is not a good option for arrays of drives larger than 1 TB. RAID5 takes a long time to rebuild and performance is slow while rebuilding. RAID5 is also not very helpful when you have many (12) disks in an array, because it only protects against one failure. A second failure ruins the whole array.
For future builds, I suggest using RAID10 instead, it will give more consistent fast performance while providing better failure tolerance.
answered Dec 3 at 19:46
Christopher Hostage
3,291928
3,291928
Yeah, thanks for the points. As is usually the case, I wasn't the one to set it up, just the one to try and fix it! I mentioned in the above comment, the array does not seem to rebuild, potentially because it's now listed as a foreign array on our Dell PERC controller. When we try to import, we can't because there are still failed (the SMART drives) drives in the array. Any thoughts on forcing it to rebuild?
– Taylor F
Dec 3 at 19:58
I haven't used Dell PERC controllers, unfortunately. Dell Support may be a better resource for you, if you can queue up a bunch of tasks to do while waiting on the phone :( . If the data on the device was backed up, it's worth figuring out the steps to restore.
– Christopher Hostage
Dec 3 at 21:01
:( indeed. Hurts when Dell Support is the next best option. Going to try and find some hardware documentation and try to parse that. Thanks for the help.
– Taylor F
Dec 3 at 21:24
add a comment |
Yeah, thanks for the points. As is usually the case, I wasn't the one to set it up, just the one to try and fix it! I mentioned in the above comment, the array does not seem to rebuild, potentially because it's now listed as a foreign array on our Dell PERC controller. When we try to import, we can't because there are still failed (the SMART drives) drives in the array. Any thoughts on forcing it to rebuild?
– Taylor F
Dec 3 at 19:58
I haven't used Dell PERC controllers, unfortunately. Dell Support may be a better resource for you, if you can queue up a bunch of tasks to do while waiting on the phone :( . If the data on the device was backed up, it's worth figuring out the steps to restore.
– Christopher Hostage
Dec 3 at 21:01
:( indeed. Hurts when Dell Support is the next best option. Going to try and find some hardware documentation and try to parse that. Thanks for the help.
– Taylor F
Dec 3 at 21:24
Yeah, thanks for the points. As is usually the case, I wasn't the one to set it up, just the one to try and fix it! I mentioned in the above comment, the array does not seem to rebuild, potentially because it's now listed as a foreign array on our Dell PERC controller. When we try to import, we can't because there are still failed (the SMART drives) drives in the array. Any thoughts on forcing it to rebuild?
– Taylor F
Dec 3 at 19:58
Yeah, thanks for the points. As is usually the case, I wasn't the one to set it up, just the one to try and fix it! I mentioned in the above comment, the array does not seem to rebuild, potentially because it's now listed as a foreign array on our Dell PERC controller. When we try to import, we can't because there are still failed (the SMART drives) drives in the array. Any thoughts on forcing it to rebuild?
– Taylor F
Dec 3 at 19:58
I haven't used Dell PERC controllers, unfortunately. Dell Support may be a better resource for you, if you can queue up a bunch of tasks to do while waiting on the phone :( . If the data on the device was backed up, it's worth figuring out the steps to restore.
– Christopher Hostage
Dec 3 at 21:01
I haven't used Dell PERC controllers, unfortunately. Dell Support may be a better resource for you, if you can queue up a bunch of tasks to do while waiting on the phone :( . If the data on the device was backed up, it's worth figuring out the steps to restore.
– Christopher Hostage
Dec 3 at 21:01
:( indeed. Hurts when Dell Support is the next best option. Going to try and find some hardware documentation and try to parse that. Thanks for the help.
– Taylor F
Dec 3 at 21:24
:( indeed. Hurts when Dell Support is the next best option. Going to try and find some hardware documentation and try to parse that. Thanks for the help.
– Taylor F
Dec 3 at 21:24
add a comment |
It is my understanding that RAID 5 allows for 1 disk failure in the array. The hotspare is built accordingly when requested. The controller/GUI or whatever front end you are using is used to do this. The time taken rebuilding the RAID is dependant on the amount of data in use. Once the hotspare is built your RAID will in theory be back to normal. In this time take one of the other drives with the SMART errors offline and rebuild it using the hotspare process. Complete until all your HDD with errors are replaced. I would replace any disk with critical data on it showing SMART errors. You could use RAID 6 going forward, of course you would have to back up all your data by moving it, rebuild the array and put it back. RAID 6 allows for more disk failures but you do take a small hit on the write speed.
Yeah this has obviously been a wake up call as to the trouble of this set up. It sounds like this process should be automatic? We did replace the failed drive and it does not appear to perform any changes to the setup. The server is using a Dell PERC, and the configuration is now listed under "foreign config." With the failed drives, it can't be loaded back into the the active configuration setting. Any thoughts on getting that to work?
– Taylor F
Dec 3 at 19:55
I just read my comment and laughed at the fact it's called a "hotspare" for a reason.. Sorry. I have used dell perc and I remember on building the raid you select the disk to use as the hotspare so should any disk fail it takes over and then a red light comes on your faulty hdd. This is the drive you replace and then that becomes the hot spare. It's all come flooding back now. My advice would be back that up ASAP and get dell support. If you don't have it, rebuild your raid ASAP on new hardware with backup. You risk losing it mate.
– jpsaunders
Dec 4 at 23:13
add a comment |
It is my understanding that RAID 5 allows for 1 disk failure in the array. The hotspare is built accordingly when requested. The controller/GUI or whatever front end you are using is used to do this. The time taken rebuilding the RAID is dependant on the amount of data in use. Once the hotspare is built your RAID will in theory be back to normal. In this time take one of the other drives with the SMART errors offline and rebuild it using the hotspare process. Complete until all your HDD with errors are replaced. I would replace any disk with critical data on it showing SMART errors. You could use RAID 6 going forward, of course you would have to back up all your data by moving it, rebuild the array and put it back. RAID 6 allows for more disk failures but you do take a small hit on the write speed.
Yeah this has obviously been a wake up call as to the trouble of this set up. It sounds like this process should be automatic? We did replace the failed drive and it does not appear to perform any changes to the setup. The server is using a Dell PERC, and the configuration is now listed under "foreign config." With the failed drives, it can't be loaded back into the the active configuration setting. Any thoughts on getting that to work?
– Taylor F
Dec 3 at 19:55
I just read my comment and laughed at the fact it's called a "hotspare" for a reason.. Sorry. I have used dell perc and I remember on building the raid you select the disk to use as the hotspare so should any disk fail it takes over and then a red light comes on your faulty hdd. This is the drive you replace and then that becomes the hot spare. It's all come flooding back now. My advice would be back that up ASAP and get dell support. If you don't have it, rebuild your raid ASAP on new hardware with backup. You risk losing it mate.
– jpsaunders
Dec 4 at 23:13
add a comment |
It is my understanding that RAID 5 allows for 1 disk failure in the array. The hotspare is built accordingly when requested. The controller/GUI or whatever front end you are using is used to do this. The time taken rebuilding the RAID is dependant on the amount of data in use. Once the hotspare is built your RAID will in theory be back to normal. In this time take one of the other drives with the SMART errors offline and rebuild it using the hotspare process. Complete until all your HDD with errors are replaced. I would replace any disk with critical data on it showing SMART errors. You could use RAID 6 going forward, of course you would have to back up all your data by moving it, rebuild the array and put it back. RAID 6 allows for more disk failures but you do take a small hit on the write speed.
It is my understanding that RAID 5 allows for 1 disk failure in the array. The hotspare is built accordingly when requested. The controller/GUI or whatever front end you are using is used to do this. The time taken rebuilding the RAID is dependant on the amount of data in use. Once the hotspare is built your RAID will in theory be back to normal. In this time take one of the other drives with the SMART errors offline and rebuild it using the hotspare process. Complete until all your HDD with errors are replaced. I would replace any disk with critical data on it showing SMART errors. You could use RAID 6 going forward, of course you would have to back up all your data by moving it, rebuild the array and put it back. RAID 6 allows for more disk failures but you do take a small hit on the write speed.
answered Dec 3 at 19:24
jpsaunders
465
465
Yeah this has obviously been a wake up call as to the trouble of this set up. It sounds like this process should be automatic? We did replace the failed drive and it does not appear to perform any changes to the setup. The server is using a Dell PERC, and the configuration is now listed under "foreign config." With the failed drives, it can't be loaded back into the the active configuration setting. Any thoughts on getting that to work?
– Taylor F
Dec 3 at 19:55
I just read my comment and laughed at the fact it's called a "hotspare" for a reason.. Sorry. I have used dell perc and I remember on building the raid you select the disk to use as the hotspare so should any disk fail it takes over and then a red light comes on your faulty hdd. This is the drive you replace and then that becomes the hot spare. It's all come flooding back now. My advice would be back that up ASAP and get dell support. If you don't have it, rebuild your raid ASAP on new hardware with backup. You risk losing it mate.
– jpsaunders
Dec 4 at 23:13
add a comment |
Yeah this has obviously been a wake up call as to the trouble of this set up. It sounds like this process should be automatic? We did replace the failed drive and it does not appear to perform any changes to the setup. The server is using a Dell PERC, and the configuration is now listed under "foreign config." With the failed drives, it can't be loaded back into the the active configuration setting. Any thoughts on getting that to work?
– Taylor F
Dec 3 at 19:55
I just read my comment and laughed at the fact it's called a "hotspare" for a reason.. Sorry. I have used dell perc and I remember on building the raid you select the disk to use as the hotspare so should any disk fail it takes over and then a red light comes on your faulty hdd. This is the drive you replace and then that becomes the hot spare. It's all come flooding back now. My advice would be back that up ASAP and get dell support. If you don't have it, rebuild your raid ASAP on new hardware with backup. You risk losing it mate.
– jpsaunders
Dec 4 at 23:13
Yeah this has obviously been a wake up call as to the trouble of this set up. It sounds like this process should be automatic? We did replace the failed drive and it does not appear to perform any changes to the setup. The server is using a Dell PERC, and the configuration is now listed under "foreign config." With the failed drives, it can't be loaded back into the the active configuration setting. Any thoughts on getting that to work?
– Taylor F
Dec 3 at 19:55
Yeah this has obviously been a wake up call as to the trouble of this set up. It sounds like this process should be automatic? We did replace the failed drive and it does not appear to perform any changes to the setup. The server is using a Dell PERC, and the configuration is now listed under "foreign config." With the failed drives, it can't be loaded back into the the active configuration setting. Any thoughts on getting that to work?
– Taylor F
Dec 3 at 19:55
I just read my comment and laughed at the fact it's called a "hotspare" for a reason.. Sorry. I have used dell perc and I remember on building the raid you select the disk to use as the hotspare so should any disk fail it takes over and then a red light comes on your faulty hdd. This is the drive you replace and then that becomes the hot spare. It's all come flooding back now. My advice would be back that up ASAP and get dell support. If you don't have it, rebuild your raid ASAP on new hardware with backup. You risk losing it mate.
– jpsaunders
Dec 4 at 23:13
I just read my comment and laughed at the fact it's called a "hotspare" for a reason.. Sorry. I have used dell perc and I remember on building the raid you select the disk to use as the hotspare so should any disk fail it takes over and then a red light comes on your faulty hdd. This is the drive you replace and then that becomes the hot spare. It's all come flooding back now. My advice would be back that up ASAP and get dell support. If you don't have it, rebuild your raid ASAP on new hardware with backup. You risk losing it mate.
– jpsaunders
Dec 4 at 23:13
add a comment |
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