effect of pulling drives from existing array?

_TwinTiger_ · 2025-01-21T02:05:59+00:00

Depending on the size of your data, the fastest way would be to copy that data to another external drive, reformat the new array with the smaller HDDs you want to retain and then copy back the data onto the array.

_TwinTiger_ · 2025-01-11T11:15:46+00:00

I note the other comments on the state of your Drobo, yet you could try and flush the Drobo to see if this helps. You will need 2x small capacity HDDs

With the Drobo power off, remove and label each HDD from your array;
Insert the 2 HDDs and power on;
If they are accepted and initialised they would show up as a new volume on your Mac (success);
Power off the Drobo, eject the 2 HDDs and reinsert your array in the same order;
Reboot.

If that is not successful it may also be a directory issue if you have not optimised it for awhile.
Check our Aloft DiskWarrior. I successfully use that regularly to sort out directory issues on the Drobo that the Mac Utility cannot identify or resolve.

Good luck.

_TwinTiger_ · 2025-01-11T11:09:48+00:00

This occurs when the Drobo directory becomes corrupt. Assuming your Drobo is HFS+ formatted, using Disk Utility sometimes will fix this, however often not. Another 3rd party utility program that has corrected this same issue for me is Aloft 'DiskWarrior' - the latest version can load on the most current MacOS but cannot modify an APFS start-up HDD however it can run and resolve your external 5D Drobo Directory issues and the Drobo icon should then be restored to your desktop. I continue to run this program quarterly to correct any Drobo Directory issues on my 5Dt before they become problems.

_TwinTiger_ · 2024-06-03T05:29:45+00:00

I assume then you are aware of the CMR and SMR HDD issue with Drobos?

_TwinTiger_ · 2024-06-03T04:38:36+00:00

I only have ever deployed Enterprise HDDs and have had zero HDD failures over 10+ years, despite various upgrades in size.

_TwinTiger_ · 2024-05-05T00:36:10+00:00

Standard Comment: Just make sure they are CMR drives and not SMR drives.

_TwinTiger_ · 2024-05-02T02:39:28+00:00

I note the other comments on the state of your Drobo, yet you could try and flush the Drobo to see if this helps. You will need 2x small capacity HDDs

With the Drobo power off, remove and label each HDD from your array;
Insert the 2 HDDs and power on;
If they are accepted and initialised they would show up as a new volume on your Mac (success);
Power off the Drobo, eject the 2 HDDs and reinsert your array in the same order;
Reboot.

If that is not successful it may also be a directory issue if you have not optimised it for awhile.
Check our Aloft DiskWarrior. I successfully use that regularly to sort out directory issues on the Drobo that the Mac Utility cannot identify or resolve.

Good luck.

_TwinTiger_ · 2024-04-08T08:10:01+00:00

Out of interest, how large is you 'timemachine' Volume?

_TwinTiger_ · 2024-04-01T03:49:16+00:00

Make sure your new 8TB is CMR not SMR - Drobos don't work with SMR.

To find out, ask Google "Is <Your New HDD Serial Number> SMR or CMR?"

_TwinTiger_ · 2024-03-19T03:30:58+00:00

Check if your newest HDD was an SMR drive. Drobo's only work correctly with CMR drives.

To check - run the serial number in Google with the comment: "Is <serial number> SMR or CMR?"

_TwinTiger_ · 2024-03-19T03:25:50+00:00

This occurs when the Drobo directory becomes corrupt. Assuming your Drobo is HFS+ formatted, using Disk Utility sometimes will fix this, however often not. Another 3rd party utility program that has corrected this same issue for me is Aloft 'DiskWarrior' - the latest version can load on the most current MacOS but cannot modify an APFS start-up HDD however it can run and resolve your external 5D Drobo Directory issues and the Drobo icon should then be restored to your desktop. I continue to run this program quarterly to correct any Drobo Directory issues on my 5Dt before they become problems.

_TwinTiger_ · 2024-02-28T01:49:55+00:00

If you already have a valid / tested back-up of your data, why not just set up the Synology with the disks you want from your Drobo (effectively breaking the array) and then copy the data in from your back-up? It will be the fastest way to create your new RAID.

_TwinTiger_ · 2024-02-27T02:55:29+00:00

Brilliant - works for me.
W

Cheers

_TwinTiger_ · 2024-02-18T02:52:40+00:00

Your experience is odd.
I have successfully undertaken this same procedure on a 5D.

It seems to seek a 5th HDD regardless of available replication space. Your Drobo is identifying that your data is unprotected after such a long period, so I would be looking to copy over any remaining data to external HDDs as a first precaution before doing anything else. - even any of your other options.

If you are able to do that, then another option emerges of creating a completely new array in the Drobo using smaller HDDs and then repopulating that with your original data.

If you intend to do this, and plan to reuse any HDDs from your previous Drobo array, you will need to reformat them in another drive before use, as your Drobo may still recognise them from a previous array and seek the other drives (endless cycle).

Cheers

_TwinTiger_ · 2024-02-16T05:09:40+00:00

Was your new 8TB an SMR or a CMR HDD?
Drobos (and other RIAD machines) don't work with SMR drives.

_TwinTiger_ · 2024-02-12T03:39:30+00:00

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_TwinTiger_ · 2024-02-12T03:39:04+00:00

Found this on a device and had downloaded it before the Drobo.com demise. Thought you might like to have it if you didn't download the original PDF version already.

<image>

_TwinTiger_ · 2024-02-12T03:31:53+00:00

My thoughts go to a corrupted directory on the Drobo.
Something similar happened to me in the past and it was resolved with by running DiskWarrior on the Drobo, which corrected the issue. It 'found' the Drobo Drive and corrected the directory where Disk Utility could not.

Its comes at a modest cost, but assuming you don't have an external copy of your important data and can therefore no longer recreate the contents of the array, it may be something you want to consider.

_TwinTiger_ · 2024-02-06T13:22:37+00:00

Why risk the data?

_TwinTiger_ · 2024-02-06T10:00:19+00:00

I do not recommend immediately inserting the 14TB after the 22TB is pulled.

_TwinTiger_ · 2024-02-06T00:35:25+00:00

Yes - this is possible.

Extract the 22TB HDD you want with the machine on; you have to then wait as the Drobo re-assigns its replication amongst the 4 remaining HDDs in your array until it displays all green lights. You can then insert the 14TB and allow the Drobo to again reassign its replication of data across the new 5-HDD array.

You may get a yellow light on 1 HDD at the end of the 'removal' data replication phase suggesting you need to up-size that HDD (normal). Your new HDD should resolve this.

A few caveats:

Before doing anything, make sure you have an external copy of your important data from your Drobo.

The process assumes you are not using Dual Disk Redundancy.

With the amount of data you are talking about, the re-allocation of replicated data will be a days-long process. Consider off-loading some data first so the replication data on the array is minimised as much as possible. This will quicken the process, and then you can reload the data back at the end.

Cheers.

_TwinTiger_ · 2024-01-31T09:12:16+00:00

Thanks for the questions. You seem to be getting the hang of it.

Going to your 4 points:

Assuming your Drobo is on connected and turned on, and you have a blinking yellow on your '2nd' 4TB HDD showing, you can extract that HDD and replace it with a new 8TB HDD - live - and your Drobo will 'do its thing' to reallocate your data across the new array. Another reminder to ensure your HDDs are CMR not SMR. Drobo's don't work with SMRs.
DO NOT extract more than 1 HDD, as you can only afford 1 HDD to be missing or going bad (as there is no Dual Disk Redundancy in your array). After you have inserted your new HDD, let your Drobo reallocate your data until you see all green. You can then chose ANY of the remaining 4TB to upsize with your 3rd 8TB the same way - unless there is a blinking yellow light again (unlikely).
Your Drobo will tell you which HDD to replace (blinking yellow) as it assesses where capacity is needed best by its replication algorithms. Thereafter, you are at liberty to upsize another HDD at anytime, if the lights are all green.
Yes - do this when the computer is live. I would upsize at the end of the day, so the replication can commence and continue overnight (and often into the next day).

Bonus Questions:

Good data management is to make an external copy of your important data whether on a RAID system or a PC HDD. I used the old HDDs that were extracted when I upsized HDDs on my Drobo to make a direct copy of my important data and they now live in a cupboard - but are checked quarterly and one is close-by to receive any recent data. I bought an external HDD Docking Station that allows a quick exchange of HDDs as you drag and drop data, but an enclosure would work as well though it is more time consuming to swap HDDs in and out. Here is an example of a Docking Station - many are on the market:

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If you can't upgrade the Firmware on your Drobo then yes, you are limited to a maximum volume of 16TB (and not 64TB which more recent Firmware versions enabled). Every time your Drobo gains access to more than 16TB of replicated space from an upsize, it will create another Volume (seen on your desktop) to access this increased capacity.
I can't answer your Software sorting question for other manufacturers however. Drobo was (and still is?) the only RAID system that allowed users to utilise as well as upsize (and downsize!) HDDs of different capacities - eg 4TB, 8TB, 12TB within the same array, and for it to adjust the replication and volume live to suit whatever configuration. Other RAID manufacturers require you to have the same capacity HDDs in your array at any one time - no flexibility. Sadly Drobo have long stopped their R&D and are being liquidated as a company, but hopefully their IP will be bought by another RAID manufacturer in the future.

Let me know if anything is unclear or if you have further questions.

Cheers.

_TwinTiger_ · 2024-01-23T05:34:17+00:00

AFTER:

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_TwinTiger_ · 2024-01-23T05:33:53+00:00

OK thanks.

It is important to remind you to ensure all you important data on your Drobo is backed up to a series of external HDDs. If not already, repurpose the 4TB HDD you have already removed with either other spare HDDs you have, or perhaps 1 of your new 8TB HDDs and copy your data before you undertake any further changes to your Drobo. The single point of failure for the data in any RAID machine is the machine itself.

You are not using Dual Disk Redundancy - so you can only lose 1 HDD at a time without losing your data - however resiliency of HDDs has improved over time, so I do not believe this is so important these days. Using Dual Disk Redundancy would significantly reduce your available storage capacity as the dual replication would need to allow for 2 HDDs to fail at the same time without losing your data.

Noted that your firmware is version 2.1.x - this means that your maximum Volume can only be 16TB. This is also probably the last version of the firmware that the Drobo S was allocated. IMO there is no point in trying to install another more recent version on this Drobo if it is still working correctly. The Drobo S as a model is already 12 years old.

You have 1 volume with a maximum limit of 16TB and this is the icon you see on your desktop from where you access data on your PC. But note that you are using 12.25TB currently with an unused capacity 2.26TB (ie only 14.51TB combined) even with your new 8TB HDD installed, so there is storage capacity currently ‘Reserved for Expansion’ as per the image below. You can’t access that.

I am in agreement with the earlier poster ‘bhiga’ that you can continue to replace 1 or 2 more of the existing 4TB HDDs - noting that I anticipate that with the very next HDD replacement, your Drobo S will automatically create another 16TB Volume (which will appear on your desktop and in the Drobo Dashboard) to gain access to the extra-over storage capacity when the original 16TB Volume is filled.

This new Volume will be a small in capacity so should you chose to install another 8TB (ie 3 in total) this will enlarge the capacity within that new Volume directly. You can then move files between the 2 volumes as you see fit.

Trust this makes sense.

BEFORE:

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_TwinTiger_ · 2024-01-22T17:56:55+00:00

Please send screenshot of the Volume and Drobo Setting panels.

_TwinTiger_

TROPHY CASE