airic499 Posted July 1, 2012 Share Posted July 1, 2012 I am sure I missed this somewhere in the 97 pages, so I apologize in advance if I did, but is there any reason why I can't use my old, now useless for much anything else Ubuntu netbook, plug in a new drive to an external port and pre-clear offline to unRaid, then add the pre-cleared drive to the unRaid box? If I read everything correctly, the preclear routine sets a "cleared" flag. I can only assume that would be recognized by unRaid on startup? I am sure this has been discussed elsewhere, but this is a huge plus to those of us who build these on the fly with DAA (disks as available), any thought as to mainstreaming this or at least making a plugin? Quote Link to comment
jbuszkie Posted July 1, 2012 Author Share Posted July 1, 2012 I often use a separate system to pre-clear my discs before I add them to the un raid array Quote Link to comment
airic499 Posted July 1, 2012 Share Posted July 1, 2012 Thanks jbuszkie, I assume something along the lines of what I have described? What should I expect to see if the process worked? My guess is I add the drive to a RAID slot, then pretty much the only option should be format right? Quote Link to comment
jbuszkie Posted July 1, 2012 Author Share Posted July 1, 2012 The process id described pretty well is the thread about the script here. It's been a while since I added a drive to the array. I use preclear on ALL my disks before they go into any system for any purpose! Follow the instruction in that thread for when the disk is done with pre-clear and you should be fine. Quote Link to comment
Joe L. Posted July 1, 2012 Share Posted July 1, 2012 Thanks jbuszkie, I assume something along the lines of what I have described? What should I expect to see if the process worked? My guess is I add the drive to a RAID slot, then pretty much the only option should be format right? You stop the array,assign the drive to an unRAID slot, then when you start the array it will present it as unformatted and show a "Format"button. Pressing it will format the drive and allow it to be used in the array. If not pre-cleared, and added to an array with established parity protection, the drive would first be cleared by unRAID. this clearing step takes many hours during which your array is off-line. It is one of the main reasons the drive preclear script was developed, to eliminate the lengthy down-time. (lime-tech used to sell pre-cleared drives, but found it impossible to compete with newegg, etc. ) When the pre-clear script is complete, a special signature is written to the drive to allow it to be recognized as pre-cleared. Quote Link to comment
airic499 Posted July 1, 2012 Share Posted July 1, 2012 Thanks all, Probably would have easily figured it out. But always nice to get some feedback before learning the hard way on a process that can take more than a day. Someone ought to mention it, but one thing I do appreciate about this forum is that (for the most part ;-), no one shoots Noobs for every question. Quote Link to comment
RobJ Posted July 1, 2012 Share Posted July 1, 2012 I have a 250GB drive I put in my xbox. Twice now it has magically come back as unformatted. So I yanked it out and ran preclear on it. I beleive I bought this as a factory reconditioned drive. I'm sure I ran pre-clear on it before I threw it in the xbox. There is also an ATA error in the smart results. Here are the results. think it should be RMA'ed?? 9 pending seems like too many.. ============================================================================ ** Changed attributes in files: /tmp/smart_start_sda /tmp/smart_finish_sda ATTRIBUTE NEW_VAL OLD_VAL FAILURE_THRESHOLD STATUS RAW_VALUE Seek_Error_Rate = 100 200 0 ok 0 Temperature_Celsius = 88 108 0 ok 55 No SMART attributes are FAILING_NOW 2 sectors were pending re-allocation before the start of the preclear. 9 sectors were pending re-allocation after pre-read in cycle 1 of 1. 0 sectors were pending re-allocation after zero of disk in cycle 1 of 1. 0 sectors are pending re-allocation at the end of the preclear, a change of -2 in the number of sectors pending re-allocation. 0 sectors had been re-allocated before the start of the preclear. 0 sectors are re-allocated at the end of the preclear, the number of sectors re-allocated did not change. ============================================================================ The final SMART report looks clean, but indicates it has had some questionable sectors, just as the Preclear report indicated, when it said that Current_Pending_Sector count rose from 2 to 9, then ended up cleared. The fact that all questionable sectors were cleared for further use seems to indicate that the drive's media surface is OK, but there was some event that scrambled the data in a few sectors, perhaps an electrical spike or sudden power outage while writing to the drive. SMART actually says there have been 319 ATA errors, but only shows the last one (which is somewhat odd, usually shows the last 5). You mention it may have been a factory reconditioned drive, so perhaps they reset some of the SMART parameters. It *claims* to be a very young drive, with only 205 hours on it. There's no reason to RMA it now, but it does seem a little suspicious. I recommend running one or two more Preclears on it, just to be sure you can trust it. Quote Link to comment
jbuszkie Posted July 2, 2012 Author Share Posted July 2, 2012 It ran another session just fine. I'm not sure what to do! I really don't like the fact that it came back as unformatted twice over the course of a couple months. Not too much of a big deal as I don't keep any of my save games on it. I'm so glad that I didn't! I guess I'll just put it back in and see if it happens again. Thanks for taking a look. Jim Quote Link to comment
Joe L. Posted July 2, 2012 Share Posted July 2, 2012 It ran another session just fine. I'm not sure what to do! I really don't like the fact that it came back as unformatted twice over the course of a couple months. Not too much of a big deal as I don't keep any of my save games on it. I'm so glad that I didn't! I guess I'll just put it back in and see if it happens again. Thanks for taking a look. Jim unformatted indicates not mounted. It could be as a result of a poor shutdown and the transactions on the drives were being replayed. That can take as long as 30 minutes or more. If you had waited, the drive might have mounted itself and then shown as expected. Unless you know WHY the drive was not mounted, you have no reason to RMA the drive. If it happens again, capture the syslog for analysis. Quote Link to comment
jbuszkie Posted July 2, 2012 Author Share Posted July 2, 2012 Joe, This is in an XBOX! :-) I wish I could get a syslog! Quote Link to comment
jbuszkie Posted July 7, 2012 Author Share Posted July 7, 2012 Joe, I put it back in the xbox and it seems to still have issues. If a disk has an issue writing a '1' will preclear find it? I'm wondering if this is my issue. should I change the script to have it write '1's instead? Maybe to make a more bullet proof test, you write '1's first and post read and then write '0's then post read again? Sure it will make the test longer.. but if it will catch more errors.... What do you think? Jim Quote Link to comment
jowi Posted July 12, 2012 Share Posted July 12, 2012 Question about the preclear progress. This is my first build and first time i'm using preclear. I'm running unRAID v5.0 rc5, and i'm trying to preclear a brand new Hitach 4TB disk (HDS724040ALE640). I know it's a lengthy process. I've watched the first 2 steps (pre-read & zeroing) which each took about 10 hours, with a speed varying from 150MB/s at start to about 95MB/s towards the end, which is pretty normal. Now the process is doing it's final post-reading, and i would assume, since the pre-read and zeroing each took 10 hours (totalling 20 hours), this also would take about 10 hours. But now, 10 hours later, it just passed 50% completion. The speed is pretty continue according to the script at about 120MB/s, which is odd, because with that speed things should be finished in 10 hours... see screenshot. What baffles me even more is that unMenu's myMAIN progress shows a rate of about 55MB/s, which is in sync with the time it takes... but why is this taking twice the time it took the prereading/zeroing? Is it normal that the post-read is twice as slow as the other parts? And what about preclear's speed indicator? Is the process still working like it should or do i have some sort of problem? Quote Link to comment
heffneil Posted July 12, 2012 Share Posted July 12, 2012 So when everything can go wrong it does! My "spare" unraid server hasn't had to reboot in forever and now I have three new 3TB drives at least 22 hours in to the preclear when I come back home and the UPS was out. My question is how if any way can I determine if the preclear was completed and completed satisfactorily if it did finish. Help with this would be appreciated and save me another day! Thanks, Neil Quote Link to comment
Joe L. Posted July 12, 2012 Share Posted July 12, 2012 So when everything can go wrong it does! My "spare" unraid server hasn't had to reboot in forever and now I have three new 3TB drives at least 22 hours in to the preclear when I come back home and the UPS was out. My question is how if any way can I determine if the preclear was completed and completed satisfactorily if it did finish. Help with this would be appreciated and save me another day! Thanks, Neil you look in /boot/preclear_reports If it completed, the reports are there. Quote Link to comment
heffneil Posted July 12, 2012 Share Posted July 12, 2012 Well that sucks nothing in there. If I was on the very last step is there a way to skip the beginning stuff and just do the last step? Thanks, Neil Quote Link to comment
jowi Posted July 12, 2012 Share Posted July 12, 2012 Is it normal that the post-read is twice as slow as the other parts? And what about preclear's speed indicator? Is the process still working like it should or do i have some sort of problem? Anyone? Quote Link to comment
Joe L. Posted July 13, 2012 Share Posted July 13, 2012 Is it normal that the post-read is twice as slow as the other parts? And what about preclear's speed indicator? Is the process still working like it should or do i have some sort of problem? Anyone? type preclear_disk.sh -? You'll see all the options. You can try the "-t" option to see if the pre-clear signature was written to the disk. That would indicate it did all but the post-read phase. Yes, you can skip the initial pre-read. Use the "-W" option. Joe L. Quote Link to comment
jowi Posted July 13, 2012 Share Posted July 13, 2012 The total process took 41 hours. I've compared the preclear report with others, to find that the 3rd part is actually twice as slow as the first two with others as well. Still would like to know why that is. Anyway, for those interested, i've included the reports for this Hitachi HDS724040ALE640 4TB disk. preclear_rpt__PK1311PAG4WKTS_2012-07-14.txt preclear_start__PK1311PAG4WKTS_2012-07-14.txt preclear_finish__PK1311PAG4WKTS_2012-07-14.txt Quote Link to comment
Joe L. Posted July 13, 2012 Share Posted July 13, 2012 I've compared the preclear report with others, to find that the 3rd part is actually twice as slow as the first two with others as well. Still would like to know why that is. Easy, the third phase is reading AND verifying that all bytes read are all zeros (they were written as zeros in the second phase). The first reading phase sends all the data read to /dev/null, and no analysis is performed. It does not care about what is read, other than to allow the disk's SMART firmware to identify un-readable sectors. It can run much faster. The verification in the third phase makes it run at about half the speed. Quote Link to comment
heffneil Posted July 13, 2012 Share Posted July 13, 2012 preclear_disk.sh -? You'll see all the options. You can try the "-t" option to see if the pre-clear signature was written to the disk. That would indicate it did all but the post-read phase. Yes, you can skip the initial pre-read. Use the "-W" option. Joe L. So for some reason I logged back in to my box and I only have two out of three Screen sessions and I initiated them all via telnet so none on console. I ran the -t on the drive I don't see in my other existing sessions and it says precleared however I don't have a report. So what should I do next. Results below: Pre-Clear unRAID Disk /dev/sda ################################################################## 1.13 Device Model: ST3000DM001-9YN166 Serial Number: W1F0RSQZ Firmware Version: CC4B User Capacity: 3,000,592,982,016 bytes Disk /dev/sda: 3000.5 GB, 3000592982016 bytes 255 heads, 63 sectors/track, 364801 cylinders, total 5860533168 sectors Units = sectors of 1 * 512 = 512 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sda1 1 4294967295 2147483647+ 0 Empty Partition 1 does not end on cylinder boundary. ######################################################################## ========================================================================1.13 == == DISK /dev/sda IS PRECLEARED with a GPT Protective MBR == ============================================================================ Thanks! Neil Quote Link to comment
Joe L. Posted July 13, 2012 Share Posted July 13, 2012 preclear_disk.sh -? You'll see all the options. You can try the "-t" option to see if the pre-clear signature was written to the disk. That would indicate it did all but the post-read phase. Yes, you can skip the initial pre-read. Use the "-W" option. Joe L. So for some reason I logged back in to my box and I only have two out of three Screen sessions and I initiated them all via telnet so none on console. I ran the -t on the drive I don't see in my other existing sessions and it says precleared however I don't have a report. So what should I do next. Results below: Pre-Clear unRAID Disk /dev/sda ################################################################## 1.13 Device Model: ST3000DM001-9YN166 Serial Number: W1F0RSQZ Firmware Version: CC4B User Capacity: 3,000,592,982,016 bytes Disk /dev/sda: 3000.5 GB, 3000592982016 bytes 255 heads, 63 sectors/track, 364801 cylinders, total 5860533168 sectors Units = sectors of 1 * 512 = 512 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sda1 1 4294967295 2147483647+ 0 Empty Partition 1 does not end on cylinder boundary. ######################################################################## ========================================================================1.13 == == DISK /dev/sda IS PRECLEARED with a GPT Protective MBR == ============================================================================ Thanks! Neil I would look in /boot/preclear_reports Quote Link to comment
heffneil Posted July 13, 2012 Share Posted July 13, 2012 Am I missing something? root@Storage3:/boot/preclear_reports# ls preclear_finish_ 5XW0DDKP_2012-03-27 preclear_finish_ 6YD0G5NN_2011-09-09 preclear_finish_ 6YD0G67X_2011-09-09 preclear_finish_ MJ1311YNG0W39A_2011-10-25 preclear_finish_ MJ1311YNG17ENA_2011-10-25 preclear_finish_ MJ1311YNG2A4SA_2011-10-25 preclear_finish_ MJ1311YNG2BXJA_2011-10-25 preclear_rpt_ 5XW0DDKP_2012-03-27 preclear_rpt_ 6YD0G5NN_2011-09-09 preclear_rpt_ 6YD0G67X_2011-09-09 preclear_rpt_ MJ1311YNG0W39A_2011-10-25 preclear_rpt_ MJ1311YNG17ENA_2011-10-25 preclear_rpt_ MJ1311YNG2A4SA_2011-10-25 preclear_rpt_ MJ1311YNG2BXJA_2011-10-25 preclear_start_ 5XW0DDKP_2012-03-27 preclear_start_ 6YD0G5NN_2011-09-09 preclear_start_ 6YD0G67X_2011-09-09 preclear_start_ MJ1311YNG0W39A_2011-10-25 preclear_start_ MJ1311YNG17ENA_2011-10-25 preclear_start_ MJ1311YNG2A4SA_2011-10-25 preclear_start_ MJ1311YNG2BXJA_2011-10-25 Quote Link to comment
heffneil Posted July 13, 2012 Share Posted July 13, 2012 None of my new drives are showing START reports either? That is unusual isn't it? Thanks, Neil Quote Link to comment
Joe L. Posted July 13, 2012 Share Posted July 13, 2012 None of my new drives are showing START reports either? That is unusual isn't it? Thanks, Neil Then the process never finished the post-read phase. Quote Link to comment
heffneil Posted July 13, 2012 Share Posted July 13, 2012 So I ran the -W with the -A and it doesn't seem to have skipped the first steps? Neil Quote Link to comment
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