Replacing a defective hard disk

[LeMarc]

Hello freenas community :)

I have a slightly older HP ProLiant MicroServer G7 N54L in which 4 of 4 hard drives are installed. The fifth hard drive (ada4), the SSD, runs FreeNAS 11 STABLE.

The problem arose that the hard disk "ada0" sooner or later (I have done a few tests with the hard drive) will have a total failure.

To avoid a total loss of data, I would like to replace this hard drive. In the German forum in the thread "FAQ - the same questions about FreeNAS 8, which are repeatedly asked / answered" (Link: https://forums.freenas.org/index.ph...mmer-wieder-gestellt-beantwortet-werden.4556/ ) is under point 4 also how this should work:

1. Determine which hard drive needs to be swapped (in this example, ada7 in a RAIDz1 / z2 named tank)
2. Identify the physical disk
3. Shut down the system
4. Remove ada7 and replace it with a new hard drive (same size or larger) on the same port
5. Turn on the system (tank will be in a DEGRADED state and / dev / ada7 will be unavailable)
6. In the command line enter zpool replace tank ada7
7. The pool will begin to recover. This can take a long time, wait until it's done.
8. You can check the status while using zpool status -v
9. After it finishes, run zpool status -v again, it will still print DEGRADED
10. Search for the device name / dev / ada7 / old
11. Enter the command zpool detach tank / dev / ada7 / old
12. Check the status again, DEGRADED and / dev / ada7 / old should be gone, and the pool status should be ONLINE
13. Enter the zpool export tank command

What makes me a little startled ... is this manual only valid if you have at least 1 free space for another hard drive in the NAS?

As already mentioned, all hard disk spaces are occupied. If I follow the instructions and replace the defective hard drive, I lose no data?

Or do I need for a smooth replacement of the defective hard drive a free slot (which I do not have)?

Sincerely, with the hope for help
Marc

 

[Alecmascot]

Why not just do what it says in the book ?

http://doc.freenas.org/11/storage.html#replacing-a-failed-drive

 

[LeMarc]

Why not just do what it says in the book ?

http://doc.freenas.org/11/storage.html#replacing-a-failed-drive

Because the book does not answer my question either.

As already explained, I have 4 of 4 hard drives installed ... I take out the defective hard drive, use the new hard drive. I follow the instructions / book ...

is my NAS / are my data in the same condition as before the exchange? Or is THIS process needed a free hard drive slot?

 

[danb35]

If I follow the instructions and replace the defective hard drive, I lose no data?

Correct, assuming your pool is set up with redundancy. Since you haven't followed the forum rules and told us anything about your installation, we can't say for sure.

But as to how to do the replacement, no, I wouldn't follow those instructions at all. Read the manual, as @Alecmascot has given you the link. If you need pictures, look here: https://forums.freenas.org/index.php?resources/replacing-a-failed-failing-disk.75/

 

[danb35]

Because the book does not answer my question either.

Yes, it does, unless you haven't asked it yet.

Or is THIS process needed a free hard drive slot?

The manual's process is:

• Offline the failing disk
• Remove the failing disk
• Install the replacement disk
• Using the GUI, replace the failing disk with the replacement

What part of that makes you think, even for a moment, that there might be any need at all for a free hard drive slot?

 

[LeMarc]

Correct, assuming your pool is set up with redundancy. Since you haven't followed the forum rules and told us anything about your installation, we can't say for sure.

But as to how to do the replacement, no, I wouldn't follow those instructions at all. Read the manual, as @Alecmascot has given you the link. If you need pictures, look here: https://forums.freenas.org/index.php?resources/replacing-a-failed-failing-disk.75/

Please excuse that I did not provide all information. freeNAS is relatively new to me.

I did not pay attention to redundancy when creating the pool. My ZFS pool currently looks like this:

Volume Status:

If you could tell me what information is needed, I will share it here.

 

[LeMarc]

Yes, it does, unless you haven't asked it yet.

The manual's process is:

• Offline the failing disk
• Remove the failing disk
• Install the replacement disk
• Using the GUI, replace the failing disk with the replacement

What part of that makes you think, even for a moment, that there might be any need at all for a free hard drive slot?

My common sense tells me if I simply swap out a hard drive full of data, that data will be lost.

Except this exchange process as it is described involves an "automatic backup" of the data.

 

[danb35]

Volume Status:

OK, yes, that's a big problem. You have no redundancy on your pool, you already have data errors, and you've been messing around with the pool at the command line. Your pool is also way too full, but that's a secondary issue at the moment.

My common sense tells me if I simply swap out a hard drive full of data, that data will be lost.

Normally no data will be lost, because most FreeNAS users (at least as far as we see here) care about their data and therefore have redundancy on their pools. You've set up your pool with no redundancy, and are seeing consequences of that--you're already losing data, and you won't be able to take a disk offline to replace it. You wouldn't just lose the data on that disk; you'd lose all the data on your pool.

Do you have another SATA port available? To make this work, you will need to have a fifth disk online temporarily. It doesn't need to be pretty, and it doesn't need to be mounted internally, but it'll need to be connected and online.

 

[LeMarc]

...(at least as far as we see here)...

Thanks for the nice but justified side blow ;)

Do you have another SATA port available?

The HP ProLiant also has an eSATA connector on the back. So it shouldn't be a problem to connect a fifth hard disk to the NAS via an adapter.

 

[danb35]

Thanks for the nice but justified side blow ;)

It actually wasn't--I only meant by that that only a small fraction of the users ever come to the forums, so anything I'd say about "most users" would really be "most users who visit the forums".

So it shouldn't be a problem to connect a fifth hard disk to the NAS via an adapter.

In that case, the way ahead is pretty straightforward:

• Attach the fifth disk.
• Using the GUI, replace ada0 with that fifth disk.
• Once replacement/resilvering completes, power down the system, remove ada0, install the replacement in its place, and reboot.

And then seriously consider migrating your pool to some sort of redundant configuration.

 

[LeMarc]

It actually wasn't--I only meant by that that only a small fraction of the users ever come to the forums, so anything I'd say about "most users" would really be "most users who visit the forums".

In that case, the way ahead is pretty straightforward:

• Attach the fifth disk.
• Using the GUI, replace ada0 with that fifth disk.
• Once replacement/resilvering completes, power down the system, remove ada0, install the replacement in its place, and reboot.

And then seriously consider migrating your pool to some sort of redundant configuration.

Thank you very much for the help! I will follow your advice when the defective hard drive is replaced. Greetings from Austria! :)

 

[Chris Moore]

Thank you very much for the help! I will follow your advice when the defective hard drive is replaced. Greetings from Austria! :)

Did you get this situation cleared up? It might be helpful for other visitors to the forum if you could share your experience.

 

[James S]

Thank you very much for the help! I will follow your advice when the defective hard drive is replaced. Greetings from Austria! :)

Greetings from Taiwan!
Equally as above... what did you do? Did it work?

 

[rayeason]

Hello and good day.

I have replaced these drives before with no problem.

However, I am now facing a problem.

There is no drive to select after replacing and clicking REPLACE.

Any advice?

I have followed the instructions here.

10. Storage — FreeNAS®11.3-RELEASE User Guide Table of Contents

www.ixsystems.com