Author Topic: LS220DE - Replacing Drive in RAID1  (Read 476 times)

Pettigrew95

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LS220DE - Replacing Drive in RAID1
« on: April 15, 2019, 05:02:49 pm »
Hey guys, quick question: I have an LS220DE with 2 drives in a RAID 1 config. The drives that comprise the RAID1 config are not the the same capacity. One of them is 4 TB and the other is 3 TB so my capacity is 3 TB and I am essentially wasting 1 TB. I want to remove the 3 TB drive and place a 4 TB in there so both drives are 4 TB. In order to do this can I just manually remove the 3 TB drive and insert the 4 TB drive? Will the RAID rebuild itself? Will there be data loss? I am assuming I can just pop out the 3 TB, put the 4 TB in and the RAID1 will rebuild itself and I will then have 4 TB usable space, there will be no data loss, or access interruption. If anyone can please confirm that would be great, thanks!

oxygen8

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Re: LS220DE - Replacing Drive in RAID1
« Reply #1 on: April 15, 2019, 11:52:49 pm »
Quote
and I will then have 4 TB usable space

no
you have to make a backup
format the nas with two 4TB discs
restore your backup

Pettigrew95

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Re: LS220DE - Replacing Drive in RAID1
« Reply #2 on: April 16, 2019, 12:40:23 pm »
Quote
and I will then have 4 TB usable space

no
you have to make a backup
format the nas with two 4TB discs
restore your backup

Thanks for the info. I am curious then what does happen if a drive in the RAID1 fails?

1000001101000

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Re: LS220DE - Replacing Drive in RAID1
« Reply #3 on: April 16, 2019, 01:38:00 pm »
The procedure you described will work in the sense that you can replace both of the original drives that way. In that case the array would still show as having 3TB usable space despite being located on 4TB drives.

There is a method to do what you describe but I don't think the buffalo firmware will do it automatically (I've never tried personally):
https://raid.wiki.kernel.org/index.php/Growing#Extending_an_existing_RAID_array

You could try connecting over ssh/telnet and see if you can make it work.

Texturtle

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Re: LS220DE - Replacing Drive in RAID1
« Reply #4 on: April 16, 2019, 01:51:40 pm »
In order to accomplish the goal you will need to delete the current RAID, replace the 3TB drive with another 4TB, and then create a new RAID 1. You will, of course, need to back up the data first.

Pettigrew95

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Re: LS220DE - Replacing Drive in RAID1
« Reply #5 on: April 16, 2019, 02:19:45 pm »
Thanks for the replies everyone. I am trying to set up a backup on my LS220DE through the web interface but there doesn't seem to be a way to get the backup to go to a Windows PC where I created a shared folder to point the LS220DE backup to. Is this possible to do?

Texturtle

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Re: LS220DE - Replacing Drive in RAID1
« Reply #6 on: April 16, 2019, 02:22:34 pm »
It can't back up to a Windows PC. It can back up to an external USB drive or to another Buffalo NAS.

Pettigrew95

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Re: LS220DE - Replacing Drive in RAID1
« Reply #7 on: April 16, 2019, 02:32:56 pm »
It can't back up to a Windows PC. It can back up to an external USB drive or to another Buffalo NAS.

So if I have a USB drive that formatted NTFS and plug that into the NAS it would recognize it and I can back up to it?

Texturtle

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Re: LS220DE - Replacing Drive in RAID1
« Reply #8 on: April 16, 2019, 02:45:02 pm »
It should recognize an NTFS drive.

Pettigrew95

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Re: LS220DE - Replacing Drive in RAID1
« Reply #9 on: April 16, 2019, 02:48:28 pm »
It should recognize an NTFS drive.

So I plugged the USB drive into the NAS and it does recognize it however I cannot browse to any of my shares now and get this error:



Is this normal or expected behavior when plugging a USB drive in?

Thanks.

Texturtle

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Re: LS220DE - Replacing Drive in RAID1
« Reply #10 on: April 16, 2019, 03:05:07 pm »
If you have SMB2 turned on for the NAS it should apply to the external drive as well. Check the SMB settings in the UI for the NAS and make sure SMB2 is enabled.

Pettigrew95

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Re: LS220DE - Replacing Drive in RAID1
« Reply #11 on: April 16, 2019, 03:14:23 pm »
If you have SMB2 turned on for the NAS it should apply to the external drive as well. Check the SMB settings in the UI for the NAS and make sure SMB2 is enabled.

SMB2 protocol is enabled.

Texturtle

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Re: LS220DE - Replacing Drive in RAID1
« Reply #12 on: April 16, 2019, 03:28:40 pm »
Then it should apply to any share on the NAS.

Pettigrew95

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Re: LS220DE - Replacing Drive in RAID1
« Reply #13 on: April 19, 2019, 11:24:35 pm »
Then it should apply to any share on the NAS.

I have a question, what would happen if I took the smaller 3 TB drive out of the NAS after powering it down first, then cloned the 3TB drive to a 4TB drive using a drive cloner, then put that cloned 4 TB drive into the NAS and powered it back up?

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Re: LS220DE - Replacing Drive in RAID1
« Reply #14 on: April 20, 2019, 08:34:13 am »

If you just clone the drive using dd you'll end up with a 4tb drive with a 3tb partition table on it. Most systems won't have a problem with it but in my experience these devices won't boot off a drive with a gpt partition table with an odd size like that. I assume this is due to how the boot loader (uboot) works. Assuming you boot from the other drive it would probably still come up. If your drive cloner automatically corrects the partition table (or you do manually) it would probably boot just fine.

Either way I believe this would leave you with a 4tb drive with 1tb of blank space at the end which may or may not be bootable by the device but would probably work with the existing raid arrays.

If as part of that process you also resized the data partition you'd end up ~3tb raid array within a ~4tb partition (or basically the same place as adding the drive blank and having the firmware add it to the existing array).   

I wouldn't recommend actually doing this, there are multiple opportunities in the process (at least while using the stock firmware) to have the system appear to function normally but quietly leave one of the drives in an unbootable state that only get's noticed when you try to replace the second drive.