How to replace/upgrade a data disks when all existing sata ports are used?

[Peaceful]

Hello,

 

Summary: Like the title says, I'm not sure how to replace a data drive when there are no open SATA ports for the new drive.

 

Back in 2010 I built my first unRAID server and it has been serving up movies and music without a hitch ever since.  late last year, I finally did a version upgrade from 4.x to 6.3.5, which went smoothly despite my considerable butt-puckering fear of losing data.  Kudos to the great documentation on the wiki and forums!  Here are my system specs:

 

- M/B: Intel - DH55HC

- CPU: Intel® Core™ i3 CPU 540 @ 3.07GHz

- Memory: 4 GB (max. installable capacity 16 GB)

- SATA Ports: 6

- SATA host adapter: SIIG SC-SA0L11-S1 PCI-Express 2.0 Low Profile Ready SATA III (6.0Gb/s) 2-Port Host Adapter

- Drives: 3xWD1002FAEX 1TB + 5xWD1001FALS 1TB for 7TB storage and 1TB Parity

- All 8 SATA ports are occupied

 

It's time to start replacing drives and this is where there is some confusion on my part:

1) The 1TB parity drive is starting to throw SMART (disc read) errors and I want to upgrade it to a newer 4TB version (will stay with the black drives as they've performed so well over the years). If I understand the wiki, replacing the parity drive is as simple as stopping the array, removing the old parity drive and installing the new one, then starting the array and rebuilding parity.

 

2) Upgrade one or more of the 1TB data drives with the newer 4TB version to increase storage capacity.  How do I do this without any open SATA ports to add a new drive?

 

Hope this isn't a dumb question.

 

Thank you,

Peaceful

[JorgeB]

2 minutes ago, Peaceful said:

But how do I replace a data drive since there are no open SATA ports to add a new drive?

Same as parity.

[trurl]

As johnnie said.

 

You had the right idea when you said "replace", but then for some reason you went off-track thinking in terms of "adding" a disk instead. Just replace the disk and unRAID will rebuild its contents to the new disk using the parity calculation. The whole point of parity is so you can rebuild a disk.

[Peaceful]

5 minutes ago, trurl said:

As johnnie said.

 

You had the right idea when you said "replace", but then for some reason you went off-track thinking in terms of "adding" a disk instead. Just replace the disk and unRAID will rebuild its contents to the new disk using the parity calculation. The whole point of parity is so you can rebuild a disk.

 

Thank you both for your quick replies!  Sorry for the confusion.  Yes, I am replacing drives, not adding new ones.  This then is the process to follow as I understand it:

 

1) Stop the array, remove the old parity drive, install the new 4TB drive, and then start the array and rebuild parity.

2) Once the parity rebuild is complete, stop the array and remove one of the existing data drives, install the new 4TB drive and then start the array again and let it rebuild the data on the new drive.

 

Seems very straight forward.  Thank you again.

Peaceful

[JonathanM]

Now is the time to start planning your transition OFF of ReiserFS.

 

Since you have no open SATA ports, it gets a little more complicated, but first, can you shuffle things around enough to completely empty one of your drives? Your answer will determine the best course of action.

[Peaceful]

16 minutes ago, jonathanm said:

Now is the time to start planning your transition OFF of ReiserFS.

 

Since you have no open SATA ports, it gets a little more complicated, but first, can you shuffle things around enough to completely empty one of your drives? Your answer will determine the best course of action.

 

Thank you for the heads-up on this change, though I'll have to do some reading to understand which file system to change to and why.  The unRAID main display reports 1.78TB of free space, so I suppose that means a 1TB drive could be emptied.

 

Peaceful

[JonathanM]

Once you get through your research, here is my short plan of action should you choose to migrate.

1. Replace parity drive and build parity on new drive.

2. Run parity check, zero errors is only acceptable outcome.

3. Pick least populated data drive, move data to other drives either manually or using unbalance plugin.

4. Stop array, change desired format of now empty 1TB drive to XFS or BTRFS, your choice based on your research. XFS is more popular, but either is a valid choice.

5. Start array, verify only empty drive shows unmountable, select and execute format.

6. Stop array, replace newly formatted drive with 4TB, rebuild.

7. Non-correcting parity check, once again only zero errors ok.

8. Fully copy data from 3 other 1TB drives to empty 4TB.

9. After verifying copy, execute steps 4 and 5 to change those drives format.

10. Repeat copy and format until all drives are no longer ReiserFS.

 

The forum is rife with examples of lockups when writing to ReiserFS. It's not universal, and it's not a guarantee, but it's enough of a percentage to be a major concern.

 

Also, the filesystem is pretty much as dead as the author's wife, since the author, Hans Reiser, was put in prison for said crime.

[Peaceful]

On 1/8/2018 at 4:57 PM, jonathanm said:

Once you get through your research, here is my short plan of action should you choose to migrate.

1. Replace parity drive and build parity on new drive.

2. Run parity check, zero errors is only acceptable outcome.

3. Pick least populated data drive, move data to other drives either manually or using unbalance plugin.

4. Stop array, change desired format of now empty 1TB drive to XFS or BTRFS, your choice based on your research. XFS is more popular, but either is a valid choice.

5. Start array, verify only empty drive shows unmountable, select and execute format.

6. Stop array, replace newly formatted drive with 4TB, rebuild.

7. Non-correcting parity check, once again only zero errors ok.

8. Fully copy data from 3 other 1TB drives to empty 4TB.

9. After verifying copy, execute steps 4 and 5 to change those drives format.

10. Repeat copy and format until all drives are no longer ReiserFS.

 

The forum is rife with examples of lockups when writing to ReiserFS. It's not universal, and it's not a guarantee, but it's enough of a percentage to be a major concern.

 

Also, the filesystem is pretty much as dead as the author's wife, since the author, Hans Reiser, was put in prison for said crime.

Jonathanm,

 

Thank you very much for detailing the exact file transition process to follow.  I do have a question: in steps 2 and 7 only zero errors is ok, so what do I do if there are errors?

 

Peaceful

[JonathanM]

14 minutes ago, Peaceful said:

  I do have a question: in steps 2 and 7 only zero errors is ok, so what do I do if there are errors?

Short answer, figure out why there are errors and correct the condition.

 

Longer answer, inspect the system log and smart reports to look for any indication of issues communicating with the drives, then act on the information and attempt the parity check again.

 

In step 2, errors mean the parity wasn't built correctly, so rerunning with corrections enabled will hopefully make the changes to make parity accurate.

In step 7, errors mean the drive rebuild wasn't successful, so normally rebuilding the drive again, possibly to a different physical drive, would be called for. In your case, step 7 is rebuilding an empty XFS filesystem, so errors can be handled a little less carefully, but still it's concerning with respect to future ability to rebuild a failed drive.

 

You should always be able to definitely point to a cause of parity errors, if you can't, it means your data is at risk. For example, a hard crash or shutdown without unmounting the array may cause parity errors, and those should be corrected with a parity check on next startup. If you get errors and nothing overt happened to cause them, you need to figure out what's happening ASAP.

[Peaceful]

Thank you again, jonathanm, for taking the time to provide a detailed answer, I really appreciate it.  I now feel confident to proceed with the drive replacement and file system change,  and am researching which drives to buy.  The plan was to us the WD blacks again, but the 4TB capacity drives are rather expensive when other acceptable options are available.

 

Cheers,

Peaceful

[Peaceful]

To close the loop on my initial question, I just ordered four of these HGST DeskStar NAS 3.5" 4TB 7200 RPM 128MB Cache SATA 6.0Gb/s High-Performance Hard Drive for Desktop NAS Systems Retail Packaging 0S04005 that are on sale at newegg for $140 plus additional promo code discount of $14 for a net cost of $126 ea.  Promo ends 1-14-18.

 

Newegg

 

Peaceful