I have a 20 bay rack mount server and will be installing 9 x 3TB hard drives to start. I want to setup 8 and copy data before adding the parity drive. At present I have 5 rows of caddies and 4 columns. I have from the top left disc 1 to disc 4 and then starting on the second row at the left disc 5 to 8 and so on with the parity drive on the bottom row at the far right of the row, i.e. disc 20. This way I always know what disc number is in which caddie including the parity drive. How can I setup unraid to do the same. will I have to mark the hard drive serial number on each caddie front before assigning them to the array so I know serial number XXXXX is for caddie/disc 1 etc. From what I have read the sda, sdb, sdc order makes know difference although I have read that sda should be assigned to the parity drive I don't think this will be possible if I don't add it from the start. All drives are connected with a LSI 9201-16i HBA card although only the server rows 1,2 and 4 are connected to it. Do you think I should leave the parity in caddie/disc 20 or move it to caddie/disc 1 position to make it easier as only row 1,2 and 4 are connected to the HBA, how do other rack mount users setup their systems. I just feel if I do this from the start I will always know which disc corresponds with which hard drive caddie in the server.

 

Thanks

Not sure that I have the best system,

but I wrote (black permanent marker) the  last few digits of the serial number of each drive onto my caddies...makes them easier to find.

In my setup, I was less concerned about the physical order of the drives than in their SATA-to-Motheboard connections. IN particular, I wanted the PARITY and the CACHE drive to light up the front panel 'drive busy' light. By plugging those two SATA cables into the MB, I can tell if there is array activity.

 

The main thing is to come up with a scheme you are comfortable with and then stick to it!

 

My process was to initially completely ignore the sda numbers.  I did the following:

• Decided how I wanted to number the disks from the perspective of the caddies
  
• Created a table for tracking caddie slot v disk serial numbers as unRAID tracks disk by serial number and not where it is connected
  
• Connected up drives, adding to the table an extra column recording where I had connected them on motherboard/disk controller ports. Not strictly necessary but useful if trying to troubleshoot any issue.
  
• Used the unRAID web GUI to allocate disks so that disk?? corresponded to the caddy?? position I wanted.  I put the cache and parity disks into the last caddy positions so that  unRAID data disk corresponded to caddy position and as I added additional disks to fill the available slots it was easy to keep the caddy position and unRAID disk?? numbers aligned.
  
• For convenience I then added an extra column where I recorded the current sd?? numbers.  I am aware this can change between boots, but as long as nothing is changed in the hardware setup it tends to the stay the same.
  

If you decide at any point to replug any drive to a different connector on the motherboard/disk controller it is a good idea to update your table to record this.

 

Not sure that I have the best system,

but I wrote (black permanent marker) the  last few digits of the serial number of each drive onto my caddies...makes them easier to find.

In my setup, I was less concerned about the physical order of the drives than in their SATA-to-Motheboard connections. IN particular, I wanted the PARITY and the CACHE drive to light up the front panel 'drive busy' light. By plugging those two SATA cables into the MB, I can tell if there is array activity.

 

Dale this is interesting, do you not have a disc activity light on all of your discs or are you not using a rack mount?

Thanks for your help.

The main thing is to come up with a scheme you are comfortable with and then stick to it!

 

My process was to initially completely ignore the sda numbers.  I did the following:

• Decided how I wanted to number the disks from the perspective of the caddies
  
• Created a table for tracking caddie slot v disk serial numbers as unRAID tracks disk by serial number and not where it is connected
  
• Connected up drives, adding to the table an extra column recording where I had connected them on motherboard/disk controller ports. Not strictly necessary but useful if trying to troubleshoot any issue.
  
• Used the unRAID web GUI to allocate disks so that disk?? corresponded to the caddy?? position I wanted.  I put the cache and parity disks into the last caddy positions so that  unRAID data disk corresponded to caddy position and as I added additional disks to fill the available slots it was easy to keep the caddy position and unRAID disk?? numbers aligned.
  
• For convenience I then added an extra column where I recorded the current sd?? numbers.  I am aware this can change between boots, but as long as nothing is changed in the hardware setup it tends to the stay the same.
  

If you decide at any point to replug any drive to a different connector on the motherboard/disk controller it is a good idea to update your table to record this.

 

Itimpi I was unaware that the sda/sdb etc numbers could change on boot, like you said its unlikely to change if the HBA cables are not moved but I did realise that the letters are assigned depending on which drive loads first. with regards to the HBA cables as mine are 8087 Im not to bothered about the positioning as I only have four cables at present, 5 if I added a LSI 9211-8i card as well but this is unlikely given I have 4TB and 3TB drives, maybe if 4K becomes mainstream I may need the space. This may seem like a dumb question but I presume the serial numbers on the WD red hard drive stickers are the same as the ones that will be shown in the unRAID devices page?

I will put the Parity the last caddie like you have done and at the moment Im not worried about a cache drive and if I was it would be a SSD so I would put it internally in the system. Thanks for your help.

Not sure that I have the best system,

but I wrote (black permanent marker) the  last few digits of the serial number of each drive onto my caddies...makes them easier to find.

In my setup, I was less concerned about the physical order of the drives than in their SATA-to-Motheboard connections. IN particular, I wanted the PARITY and the CACHE drive to light up the front panel 'drive busy' light. By plugging those two SATA cables into the MB, I can tell if there is array activity.

 

Dale this is interesting, do you not have a disc activity light on all of your discs or are you not using a rack mount?

Thanks for your help.

I have 4 MB onboard SATA sockets, and a 4 port addin card that doesn't drive the activity light on the front panel...so I put data drives on the add-in card. All writes go to cache first...so that's easy...and then MOVER causes Parity to light up.  "Reading" from the data drives on the extension card is just invisible...but hopefully, there's a movie or tunes showing up somewhere.

I have a 20 bay rack mount server and will be installing 9 x 3TB hard drives to start. I want to setup 8 and copy data before adding the parity drive. At present I have 5 rows of caddies and 4 columns. I have from the top left disc 1 to disc 4 and then starting on the second row at the left disc 5 to 8 and so on with the parity drive on the bottom row at the far right of the row, i.e. disc 20. This way I always know what disc number is in which caddie including the parity drive. How can I setup unraid to do the same. will I have to mark the hard drive serial number on each caddie front before assigning them to the array so I know serial number XXXXX is for caddie/disc 1 etc. From what I have read the sda, sdb, sdc order makes know difference although I have read that sda should be assigned to the parity drive I don't think this will be possible if I don't add it from the start. All drives are connected with a LSI 9201-16i HBA card although only the server rows 1,2 and 4 are connected to it. Do you think I should leave the parity in caddie/disc 20 or move it to caddie/disc 1 position to make it easier as only row 1,2 and 4 are connected to the HBA, how do other rack mount users setup their systems. I just feel if I do this from the start I will always know which disc corresponds with which hard drive caddie in the server.

 

Thanks

 

I vaguely recall reading that the Norco backplanes go right to left, but I could be wrong.  I knew the definitive answer to this back when I built "Tower".  With 5.0.5+ (if I remember correctly) I don't think it matters anymore which port the hard drives are on.  Just have to remember which serial numbers are what (i.e. disc1, disc2, parity, etc.).  If that is the case (I haven't any inclination to test it unnecessarily lol), then you could pull all the drives and change up where they are, then when unRAID is started again, it will want you to configure what is what.

 

I thought about using my label maker, but, then that would have blocked the air vents of the caddies.  So instead, I used excel making a 4x6 grid (I have the 4224's) entering the serial numbers into the corresponding field/box then printed it.  I saved this excel spreadsheet onto the USB drive too, just incase I were to misplace the print out.

 

Not sure if I'm right about the right to left "numbering" of the backplanes, but I can tell you I have my parity in the upper right most bay and my cache in the lower left most bay, fwiw.

 

One Tip for when you complete the build...

Open the Web Gui and take a Screen Shot of the first page. It shows all the disk drives' serial numbers.

Save the screen shot somewhere (dropbox?) NOT on the unRAID server.

Should something happen, the ONLY two serial numbers that are important if you need to rebuild the server are those for PARITY DRIVE and CACHE DRIVE.    Assuming the array was stable when you started down the rebuild path, the PARITY drive will show up as 'unformatted' and can thus be determined. BUT, if there's a data disk problem, and for some reason TWO drives are showing up as unformatted (Perhaps you had to replace a failed drive?) THEN, you must be absolutely sure you can Identify the Parity drive correctly.  In this example, the replaced drive can be rebuilt safely from the correctly identified parity (Plus all the other data disks.)

 

Thanks for all your help guys, its appreciated. As it doesn't matter to much about disc placement except for parity and cache I think I will run left to right, drop a row and run left to right again and so on and put my parity in caddie 20, the bottom right corner. You all gave me some useful information especially about the screenshot for drive placement in the web gui, which I had already read about but its nice to understand how important it is, especially for parity and cache drives.

Instead of, or in addition to, saving a screenshot of the unRAID disk configuration you may want to keep a spreadsheet of physical disk locations. I made the one below using Google Drive because my drive bays don't have much room for stickers. It's also a lot easier to update than stickers.