SSD

What disk drives are you running. 2T Samsungs have a bug called "silent corruption" that may be able to cause the symptoms you are seeing. What motherboard are you running. Some motherboards don't work well. That doesn't always mean they won't run at all, but can mean that they don't run reliably. Your may have one of those. Suggest you post full system specs and a full syslog.

Glad to help. Hope you are able to solve your issue!

You can run smart reports on each drive and look for errors there. You can also double check your cabling to your drives. Read on, however. I suspect your issues are not drive or cable related. unRAID calculates parity by adding the corresponding bits of your data disks. If the result is odd, parity is set to one. If the result is even, parity is set to zero. In this way, the corresponding bits added together across all the disks is always even. So if unRAID finds that the sum is odd during a parity check, you have a sync error. Very simple. When unRAID finds this, it has no idea which disk changed, but what it will do is update parity to make the bits add up to to be even again. Some people call this correcting the parity error - but "correct" may not be the best term. If is a very syntactic "correction". Now lets say your array is perfect, parity is perfect, and you run a parity check. The parity check will have zero sync errors. But let's throw is a bad memory chip - say one that results in a flipped bit 1 in a trillion times. So your parity check is running along perfectly, and the memory error occurs in the memory buffer of disk contents. unRAID trusts that the memory contains an exact copy of the data from the disk. So unRAID will see a parity mismatch and update parity to be consistant with the bad read. With this happening 1 in a trillion times, and you have 10 2T drives, you might expect to see 40 or so sync errors. Now, after the parity check, parity is NOT perfect. On 40 places on the disk, parity has been mistakenly updated because of the memory error. Now let's say you buy new memory, run it through a weeklong memtst and KNOW the memory is perfect. You now run a parity check. What will be the result? 40 sync errors. What it did was to CORRECT the 40 mistakes it made the last time. But what if you didn't replace the bad memory and ran it again. The chances of the memory error affecting EXACTLY the same disk locations are staggeringly low. So what will happen in in about 40 new spots memory will get corrected, and unRAID will adjust parity (incorrectly), but in the spots that were memory corrupted on the last parity check, unRAID will correct parity. Net result, ~80 sync errors. You are still left with ~40 bad parity situations on your disk. It is possible that your system memory is fine and the one of the disks or disk controllers or chipset is corrupting the information before it gets to your computer's memory. Drives have protections to prevent this, but it is still possible. But it is far easier to rule out the memory first. It is fairly common - especially if you are running 2 sticks. One thing you can look at are the parity mismatch locations in your syslog. If you are seeing the same sector marked bad and then marked good on the next parity check, if usually means you have a memory error. And remember, when you finally fix the problem, you will still have one more parity check with sync errors that will truly correct parity. After that, sync errors should be zero. Many users that find a bad memory chip are frustrated to find that it didn't fix the problem because the next parity check results in sync errors. They don't realize that this really did correct parity and the next parity check will be perfect. Hope this helps. Good luck!

My guess is you have a bad memory stick. Run memtst.

I believe the drive is supposed to do pre-emptive reallocations when it has trouble reading data but is ultimately successful. Without such a feature, a parity check would almost never result in a reallocated sector. Am I missing something?

Good to go. Add it to your array and enjoy your new drive!

what about me? Sorry - I use my iPhone and read forum in text mode first thing in the morning. Can't see embedded images. But I just took a look. Something is not right obviously. Suggest you wait for Joe L. who wrote the preclear script. He can probably explain what could cause this.

Cherritaker - your disks look good! No sign of reallocated sectors. Add them to your array and enjoy!

redia - Looks good. Of course, this is only showing the difference between the smart report before doing the preclear, and the smart report after doing the preclear. If the disk had a serous problem before you started and didn't get worse in the preclear, this would not show it.

The reallocated sector count at 216 is a definite problem. It is encouraging that you were able to preclear the disk without the count increasing! Otherwise the difference would have been highlighted by the preclear output. But I have never seen a drive with more than 1 or 2 reallocated sectors that didn't continue to degrade with each parity check (although I've read reports of people with over 100 that have held steady). If this disk were in the array, I would suggest that you run a parity verify (read only parity check) and see if the 216 number holds steady. If it did, I would suggest running another one. If you could run 3 in a row and not have the number increase, maybe the drive is okay. But since you are in the preclear stage, you might want to run it through 3 preclear cycles. If the number holds steady, I'd consider trusting the disk. But it would be a world's record of most reallocated sectors on a stable disk from all the smart output I've seen! The other attribute to monitor closely is the current_pending_sector. This is the number of sectors that have been flagged to be reallocated. You did not post this value. The "raw read error rate" is nothing to be overly concerned about unless and until you start to get close to the threshold for failure. And you are no where close. This is a good example of where the diff list of pre-preclear smart output and post-preclear smart output is not sufficient to identify all problems.

Welcome to the unRAID Forums! Most of the documentation for unRAID is available via the Wiki. Below are links to some of the highlights to help new users get started. Getting Started with unRAID A guide for new users of unRAID FAQ Frequently Asked Questions Un-Official unRAID Manual A copy of the unRAID user-manual edited by owners of unRAID to be more accurate, up to date, and complete than the official version. Best of the Forums Some of the best forum threads identified by unRAID users Troubleshooting When requesting assistance from unRAID community members a description of the symptoms of your issue is a good start, but frequently not sufficient to diagnose the cause. The information needed to perform an analysis is mostly contained in the system log and/or smart reports. The troubleshooting section of the wiki describes how to capture these files, which can then be zipped and attached to requests for assistance. unMenu and myMain Add ons developed by community members unRAID WIKI The unRAID wiki, has two sections. The "Official" section edited by lime-technology, the "Un-Official" section edited by users of unRAID. Recommended Builds Common builds using hardware known to be compatible with unRAID, a good starting place if you are interested in building your own unRAID server. unRAID Roadmap Lists the planned new features and enhancements by version. Also shows progress by feature in the next build. Check back often. unRAID Configuration Guide Step by step instructions to configure a new array with some popular unRAID addons. Welcome aboard! Here are links to some old stickies that may still be of interest to some users: EARS Jumpered / Unjumpered Thread Release Information ACPI Questions? Will server Power button gracefully shut down the server? To Cache drive or not to Cache drive? How-To: Migrate from unRAID 4.7 to unRAID 5.0 Remove Drive Without Losing Parity - The unRAID Moderators

Smart report looks fine. Suggest you post the full syslog for one of the Linux experts to look at. First thought is a cabling problem.

Was this a brand new drive when you started? There were 38 pending sectors when the preclear began. A pending sector basically means that the drive thinks it is a bad sector but has not been able to reallocate it yet. After there preclear, you have 44 reallocated sectors (this means that the drive has marked them as bad and "mapped" spare sectors to replace them). This is a good thing, as if effectively repairs those bad sectors. But you also have 149 pending sectors. There are also 44 reallocated events (representing the 44 reallocated sectors). This is a pretty bad condition. You could run another preclear cycle on the drive. If the drive is good, you'd expect that the 149 pending sectors would get reallocated (leaving 193 reallocated sectors, and no pending sectors). If that happened, and the count didn't increase under stress, the drive would be ok. But the odds are way against that happening. When this many sectors are being reallocated it is normally downhill. Long story short - you don't want to trust your data to this drive. RMA it.

I would not keep running. RMA the disk.

Just wanted to point out that you cannot draw conclusions about whether a drives is failing by looking at the syslog. Only by seeing reallocated sectors or or failed attributes in a smart report will you know the drive itself in the problem. It is MUCH more common for syslog errors to be traced back to a cabling / backplane issue. So look at your SMART report and confirm the reallocated sectors are increasing. Otherwise you may have cabling issues in addition to a suspect disk.

The long smart test ran successfully. I moved the disk to a different controller and ran preclear successfully (so disk is okay). The smart report error I was getting suggested running with the "-T permissive" option. When I added that to the command, it worked. So I think that has more to do with the controller than with the preclear error (I confirmed this on other ports). My other controllers don't requrie this permissive option. Joe L., you might want to add the permissive option to your unmain and preclear scripts. I still don't know why I got those 2 errors preclearing the disk. But I've now reseated all of the cables and plan to continue to run preclear tests. Here is the error I was seeing in case someone is searching for the forum looking for this error: smartctl version 5.38 [i486-slackware-linux-gnu] Copyright © 2002-8 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Device Model: Hitachi HDS722020ALA330 Serial Number: JK11A5YAKDBxxx Firmware Version: JKAOA3EA User Capacity: 2,000,398,934,016 bytes Device is: Not in smartctl database [for details use: -P showall] ATA Version is: 8 ATA Standard is: ATA-8-ACS revision 4 Local Time is: Sat Oct 2 13:52:13 2010 EDT SMART support is: Available - device has SMART capability. SMART support is: Enabled Error SMART Status command failed Please get assistance from http://smartmontools.sourceforge.net/ Register values returned from SMART Status command are: ST =0x50 ERR=0x00 NS =0x00 SC =0xc8 CL =0x43 CH =0x3b SEL=0x40 A mandatory SMART command failed: exiting. To continue, add one or more '-T permissive' options.

Thanks! Will check back tonight and see how it did. I am doing a big copy operation on array right now. Hope it will be done tonight so I can take the server down and check all of the connections. Trouble is, I don't have a very reliable way to tell if the problem is fixed.

Ok - so I decided to run a short and a long smart test. The short test ran and completed. The long test seemed to start, but when I checked on progress, it seemed as though it had forgotten about the request ... root@Tower:~# smartctl -d ata -tlong /dev/sdb smartctl version 5.38 [i486-slackware-linux-gnu] Copyright © 2002-8 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF OFFLINE IMMEDIATE AND SELF-TEST SECTION === Sending command: "Execute SMART Extended self-test routine immediately in off-line mode". Drive command "Execute SMART Extended self-test routine immediately in off-line mode" successful. Testing has begun. Please wait 255 minutes for test to complete. Test will complete after Thu Sep 30 16:01:42 2010 Use smartctl -X to abort test. <about 20 minutes passed> root@Tower:~# smartctl -a -d ata /dev/sdb smartctl version 5.38 [i486-slackware-linux-gnu] Copyright © 2002-8 Bruce Allen Home page is http://smartmontools.sourceforge.net/ === START OF INFORMATION SECTION === Device Model: Hitachi HDS722020ALA330 Serial Number: JK11A5YAKDWW3X Firmware Version: JKAOA3EA User Capacity: 2,000,398,934,016 bytes Device is: Not in smartctl database [for details use: -P showall] ATA Version is: 8 ATA Standard is: ATA-8-ACS revision 4 Local Time is: Thu Sep 30 11:58:57 2010 EDT SMART support is: Available - device has SMART capability. SMART support is: Enabled === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: PASSED General SMART Values: Offline data collection status: (0x85) Offline data collection activity was aborted by an interrupting command from host. Auto Offline Data Collection: Enabled. Self-test execution status: ( 249) Self-test routine in progress... 90% of test remaining. Total time to complete Offline data collection: (23212) seconds. Offline data collection capabilities: (0x5b) SMART execute Offline immediate. Auto Offline data collection on/off support. Suspend Offline collection upon new command. Offline surface scan supported. Self-test supported. No Conveyance Self-test supported. Selective Self-test supported. SMART capabilities: (0x0003) Saves SMART data before entering power-saving mode. Supports SMART auto save timer. Error logging capability: (0x01) Error logging supported. General Purpose Logging supported. Short self-test routine recommended polling time: ( 1) minutes. Extended self-test routine recommended polling time: ( 255) minutes. SCT capabilities: (0x003d) SCT Status supported. SCT Feature Control supported. SCT Data Table supported. SMART Attributes Data Structure revision number: 16 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x000b 100 100 016 Pre-fail Always - 0 2 Throughput_Performance 0x0005 131 131 054 Pre-fail Offline - 109 3 Spin_Up_Time 0x0007 100 100 024 Pre-fail Always - 0 4 Start_Stop_Count 0x0012 100 100 000 Old_age Always - 3 5 Reallocated_Sector_Ct 0x0033 100 100 005 Pre-fail Always - 0 7 Seek_Error_Rate 0x000b 100 100 067 Pre-fail Always - 0 8 Seek_Time_Performance 0x0005 121 121 020 Pre-fail Offline - 35 9 Power_On_Hours 0x0012 100 100 000 Old_age Always - 37 10 Spin_Retry_Count 0x0013 100 100 060 Pre-fail Always - 0 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 3 192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 3 193 Load_Cycle_Count 0x0012 100 100 000 Old_age Always - 3 194 Temperature_Celsius 0x0002 181 181 000 Old_age Always - 33 (Lifetime Min/Max 25/36) 196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 0 197 Current_Pending_Sector 0x0022 100 100 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0008 100 100 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x000a 200 200 000 Old_age Always - 0 SMART Error Log Version: 0 No Errors Logged SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error # 1 Short offline Completed without error 00% 37 - <Shouldn't there be a row here saying the Long test was running??> SMART Selective self-test log data structure revision number 1 SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS 1 0 0 Not_testing 2 0 0 Not_testing 3 0 0 Not_testing 4 0 0 Not_testing 5 0 0 Not_testing Selective self-test flags (0x0): After scanning selected spans, do NOT read-scan remainder of disk. If Selective self-test is pending on power-up, resume after 0 minute delay.

Contents of postread_errorssdb skip=135200 count=200 returned instead of 00000 skip=149000 count=200 returned instead of 00000 Also forgot to report - the disk was occasionally reporting in standby (not spinnning) while preclear was occurring.

Thought these unusual results might be of interest to Joe and/or others. I ran a preclear on a disk in a port I had not used on my backplane. Drive seemed to be recognized but noticed that smart reports were failing (see bolded section below) while disk was being precleared. Sometimes it worked, sometimes it got this error. Was moving along at a good clip and finished this morning. unRAID is reporting non-zero values on the drive. Finding issues like this is why we run preclear scripts! I am going to experiement further to see if I have a loose cable or something, or if the drive itself is bad. Question about the non-zero values ... would preclear continue to search the entire drive before reporting non-zero values on the drive, or stop immediately when it hit one? Since it appeared to go all the way through the entire disk, is there any way to know how many or where these non-zero values are? Thanks Joe for this great tool. Saved me from a nightmare if this had been added to the array! Sep 30 07:54:32 Tower preclear_disk-finish[6363]: smartctl version 5.38 [i486-slackware-linux-gnu] Copyright © 2002-8 Bruce Allen Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Home page is http://smartmontools.sourceforge.net/ Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: === START OF INFORMATION SECTION === Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Device Model: Hitachi HDS722020ALA330 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Serial Number: JK11A5YAKDWW3X Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Firmware Version: JKAOA3EA Sep 30 07:54:32 Tower preclear_disk-finish[6363]: User Capacity: 2,000,398,934,016 bytes Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Device is: Not in smartctl database [for details use: -P showall] Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ATA Version is: 8 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ATA Standard is: ATA-8-ACS revision 4 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Local Time is: Thu Sep 30 07:54:31 2010 EDT Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SMART support is: Available - device has SMART capability. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SMART support is: Enabled Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: === START OF READ SMART DATA SECTION === Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SMART overall-health self-assessment test result: PASSED Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: General SMART Values: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Offline data collection status: (0x84)^IOffline data collection activity Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^Iwas suspended by an interrupting command from host. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^IAuto Offline Data Collection: Enabled. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Self-test execution status: ( 0)^IThe previous self-test routine completed Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^Iwithout error or no self-test has ever Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^Ibeen run. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Total time to complete Offline Sep 30 07:54:32 Tower preclear_disk-finish[6363]: data collection: ^I^I (23212) seconds. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Offline data collection Sep 30 07:54:32 Tower preclear_disk-finish[6363]: capabilities: ^I^I^I (0x5b) SMART execute Offline immediate. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^IAuto Offline data collection on/off support. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^ISuspend Offline collection upon new Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^Icommand. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^IOffline surface scan supported. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^ISelf-test supported. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^INo Conveyance Self-test supported. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^ISelective Self-test supported. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SMART capabilities: (0x0003)^ISaves SMART data before entering Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^Ipower-saving mode. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^ISupports SMART auto save timer. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Error logging capability: (0x01)^IError logging supported. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^IGeneral Purpose Logging supported. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Short self-test routine Sep 30 07:54:32 Tower preclear_disk-finish[6363]: recommended polling time: ^I ( 1) minutes. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Extended self-test routine Sep 30 07:54:32 Tower preclear_disk-finish[6363]: recommended polling time: ^I ( 255) minutes. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SCT capabilities: ^I (0x003d)^ISCT Status supported. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^ISCT Feature Control supported. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ^I^I^I^I^ISCT Data Table supported. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SMART Attributes Data Structure revision number: 16 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Vendor Specific SMART Attributes with Thresholds: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 1 Raw_Read_Error_Rate 0x000b 100 100 016 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 2 Throughput_Performance 0x0005 100 100 054 Pre-fail Offline - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 3 Spin_Up_Time 0x0007 100 100 024 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 4 Start_Stop_Count 0x0012 100 100 000 Old_age Always - 3 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 5 Reallocated_Sector_Ct 0x0033 100 100 005 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 7 Seek_Error_Rate 0x000b 100 100 067 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 8 Seek_Time_Performance 0x0005 100 100 020 Pre-fail Offline - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 9 Power_On_Hours 0x0012 100 100 000 Old_age Always - 33 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 10 Spin_Retry_Count 0x0013 100 100 060 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 3 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 3 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 193 Load_Cycle_Count 0x0012 100 100 000 Old_age Always - 3 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 197 Current_Pending_Sector 0x0022 100 100 000 Old_age Always - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 198 Offline_Uncorrectable 0x0008 100 100 000 Old_age Offline - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 199 UDMA_CRC_Error_Count 0x000a 200 200 000 Old_age Always - 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SMART Error Log Version: 0 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: No Errors Logged Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SMART Self-test log structure revision number 1 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: No self-tests have been logged. [To run self-tests, use: smartctl -t] Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SMART Selective self-test log data structure revision number 1 Sep 30 07:54:32 Tower preclear_disk-finish[6363]: SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 1 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 2 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 3 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 4 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-finish[6363]: 5 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Selective self-test flags (0x0): Sep 30 07:54:32 Tower preclear_disk-finish[6363]: After scanning selected spans, do NOT read-scan remainder of disk. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: If Selective self-test is pending on power-up, resume after 0 minute delay. Sep 30 07:54:32 Tower preclear_disk-finish[6363]: Sep 30 07:54:32 Tower preclear_disk-diff[6376]: ============================================================================ Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Disk /dev/sdb has NOT been successfully precleared Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Postread detected un-expected non-zero bytes on disk== Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Ran 1 preclear-disk cycle Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Using :Read block size = 8225280 Bytes Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Last Cycle's Pre Read Time : 6:34:23 (84 MB/s) Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Last Cycle's Zeroing time : 5:45:35 (96 MB/s) Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Last Cycle's Post Read Time : 20:32:46 (27 MB/s) Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Last Cycle's Total Time : 32:53:57 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Total Elapsed Time 32:53:57 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Disk Start Temperature: 34C Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Current Disk Temperature: 32C, Sep 30 07:54:32 Tower preclear_disk-diff[6376]: == Sep 30 07:54:32 Tower preclear_disk-diff[6376]: ============================================================================ Sep 30 07:54:32 Tower preclear_disk-diff[6376]: S.M.A.R.T. error count differences detected after pre-clear Sep 30 07:54:32 Tower preclear_disk-diff[6376]: note, some 'raw' values may change, but not be an indication of a problem Sep 30 07:54:32 Tower preclear_disk-diff[6376]: 15,25c15,85 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < Error SMART Status command failed Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < Please get assistance from http://smartmontools.sourceforge.net/ Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < Register values returned from SMART Status command are: Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < ST =0x50 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < ERR=0x00 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < NS =0x08 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < SC =0xa0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < CL =0x88 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < CH =0xe0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < SEL=0x40 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: < A mandatory SMART command failed: exiting. To continue, add one or more '-T permissive' options. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: --- Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > === START OF READ SMART DATA SECTION === Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > SMART overall-health self-assessment test result: PASSED Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > General SMART Values: Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Offline data collection status: (0x84)^IOffline data collection activity Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^Iwas suspended by an interrupting command from host. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^IAuto Offline Data Collection: Enabled. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Self-test execution status: ( 0)^IThe previous self-test routine completed Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^Iwithout error or no self-test has ever Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^Ibeen run. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Total time to complete Offline Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > data collection: ^I^I (23212) seconds. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Offline data collection Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > capabilities: ^I^I^I (0x5b) SMART execute Offline immediate. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^IAuto Offline data collection on/off support. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^ISuspend Offline collection upon new Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^Icommand. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^IOffline surface scan supported. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^ISelf-test supported. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^INo Conveyance Self-test supported. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^ISelective Self-test supported. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > SMART capabilities: (0x0003)^ISaves SMART data before entering Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^Ipower-saving mode. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^ISupports SMART auto save timer. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Error logging capability: (0x01)^IError logging supported. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^IGeneral Purpose Logging supported. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Short self-test routine Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > recommended polling time: ^I ( 1) minutes. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Extended self-test routine Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > recommended polling time: ^I ( 255) minutes. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > SCT capabilities: ^I (0x003d)^ISCT Status supported. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^ISCT Feature Control supported. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ^I^I^I^I^ISCT Data Table supported. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > SMART Attributes Data Structure revision number: 16 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Vendor Specific SMART Attributes with Thresholds: Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 1 Raw_Read_Error_Rate 0x000b 100 100 016 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 2 Throughput_Performance 0x0005 100 100 054 Pre-fail Offline - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 3 Spin_Up_Time 0x0007 100 100 024 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 4 Start_Stop_Count 0x0012 100 100 000 Old_age Always - 3 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 5 Reallocated_Sector_Ct 0x0033 100 100 005 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 7 Seek_Error_Rate 0x000b 100 100 067 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 8 Seek_Time_Performance 0x0005 100 100 020 Pre-fail Offline - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 10 Spin_Retry_Count 0x0013 100 100 060 Pre-fail Always - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 3 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 3 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 193 Load_Cycle_Count 0x0012 100 100 000 Old_age Always - 3 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 196 Reallocated_Event_Count 0x0032 100 100 000 Old_age Always - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 197 Current_Pending_Sector 0x0022 100 100 000 Old_age Always - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 198 Offline_Uncorrectable 0x0008 100 100 000 Old_age Offline - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 199 UDMA_CRC_Error_Count 0x000a 200 200 000 Old_age Always - 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > SMART Error Log Version: 0 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > No Errors Logged Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > SMART Self-test log structure revision number 1 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > No self-tests have been logged. [To run self-tests, use: smartctl -t] Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > SMART Selective self-test log data structure revision number 1 Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 1 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 2 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 3 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 4 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > 5 0 0 Not_testing Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Selective self-test flags (0x0): Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > After scanning selected spans, do NOT read-scan remainder of disk. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > If Selective self-test is pending on power-up, resume after 0 minute delay. Sep 30 07:54:32 Tower preclear_disk-diff[6376]: > Sep 30 07:54:32 Tower preclear_disk-diff[6376]: ============================================================================ Sep 30 07:54:32 Tower preclear_disk-diff[6376]:

Joe - this is an amazing job! Craftsmanship is outstanding (much better than a hack lke me). Having done the dremeling job on several cases, I know what a job it is to do. Cutting out perfect circles is near impossible!! Love the way you were able to incorporate the home-made drive rack into the case. Much more functional than mine - which requires removal of the entire rack to replace a drive. Although you may have only spent $27.99 on the case, there must be hundreds of dollars of sweat equity invested! Sorry I am late responding - just seeing this today. Thanks for sharing! Best, Brian

I have a custom molex power rail (there's a picture of it somewhere on the forum) that powers 10 drives (all green) off of a single molex (directly from the PSU). I have not had any problems. I specifically held the molex in question while powering up to see if it got hot - and it did not. Not in the slightest. I cannot advise anyone else to brazenly ignore the specs on the molex connector as I have, but this has been my experience.

Here is a better picture that shows the distance between drives. It is a bit more than 1/8". But I do have fans blowing fresh air into the case. My drives run VERY cool (maybe cooler than healthy according to some reports). Note that there is more spacing between the top drive and the drive below it. This was by design because I knew there was not as much direct airflow at the top.

Experience here has been that ANY reallocated sector count is a bad sign. I agree that if it holds stable (even at 100 or more) it is nothing to worry about, but experience here has shown that even a small number of reallocated sectors usually lead to more (and more and more ...). You might think of it like a string hanging from your favorite shirt. Pull on it and the entire shirt will unravel. The fact that you've run several cycles and the number has held steady is comforting and not typical of the unraveling behavior. I'd still recommend diligence in making sure that the count doesn't increase further.

Some recovery tools will remap bad sectors and fill the remapped sector with some searchable string like "UNRECOVERABLE DATA UNRECOVERABLE DATA ..." so that, after recovery, the user could search the files for that string and figure out what file(s) were impacted. Having unRAID do something similar during a drive rebuild would be a nice enhancement. It would allow a user to be able to figure out what got corrupted, rather than just knowing something got trampled with no means to figure out what it was. No real harm in it - if you get a bad read you know that sector is not going to rebuild correctly - might just as well put something identifyable in there. You'd likely want to do this on both the restored disk AND the disk that gave the read error (unless it was parity). Corresponding info should be in the syslog to guide a person to the affected drives. I think that this would be a great advertising point! "Stripe kill" is such a hot topic of criticism of RAID-5. A robust story to tell about how unRAID gracefully handles this deadly (and relatively common) occurrence, giving the user the ability to recover most all of their data and the tools to figure out what, if anything, got corrupted, would be a great selling point IMO.