Follow up to Drobo 5N issue and fix

In the previous post I wrote about finding the issue by doing a slot flush on each drive.  When I reached the 4th drive the slot flush did not work, and the Drobo exhibited the same pattern I saw when attempting to boot it.

Having no other answers to what I was seeing I made the assumption that drive 4 was bad.  I went to the store and bought an identical drive of same size and speed.  With the Drobo powered off, I removed the old drive in slot 4 and inserted the new drive.  I also verified that all 5 drives were securely locked in.

I powered on the Drobo and within a relatively short period of time was able to once again gain access to it through the Drobo Dashboard software.  It showed me that Data Protection was running and estimated (way too high) how long until the new drive would be rebuilt.

I do have a 64GB m-SATA drive (accelerator) in the slot on the bottom of the Drobo 5N.  I'm not sure if this made a difference but aside from what the Dashboard reported as the amount of time to for data protection to restore the new drive, the actual time ended up being about 11 hours.  This is on a unit with a total of 20TB of drive space, and about 14.9TB usable.  I had used 80% so this device was close to full.  The Dashboard started off saying it would be 93 hours to restore.  That estimate went down over time but still remained higher than the actual time.

I am not sure if the m-SATA helped speed things up, or if the fact I use 7200RPM drives helped, but I wanted to let others know the restore can happen relatively quickly.  I have read where other's have taken days.

I wanted to make sure nothing attempted to write to the device during the restore so I disabled anything I use that might have tried to write to the Drobo during the restore.  One thing that is incredibly nice was I had access to my data during the restore process.

I hope this additional information answers some questions others may have if they go through the same experience I did.

My Drobo 5N nightmare (it didn't tell me I lost a drive)

I have a Drobo 5N with (5) x 4TB Hard drives in it.  It also has a 64GB m-SATA accelerator drive.  The Drobo was working Wednesday night and Thursday when I woke up it had no lights except a solid orange power light.  I did troubleshooting the first day but made no progress.

Here is what I saw:

1. Power on, drive lights all solid orange, power light green, cycling quickly through colors.  
2. Next, side drive lights all go out, power light flashes green, blue lights move from sides to center
3. Power light continues to flash green, blue led's at bottom move from left to right stopping on third light from left, the moving on to right.  In the end I would end up with this:
1. 00X0000XXX (x is a illuminated blue led).
4. Power light would continue to flash green, and eventually turn orange and blue led's would all go out.  It would sit with solid orange power light for a while and then restart the whole process over.

The next day I tried contacting Drobo and as usual (support in general) I got waived off unless I wanted to purchase a one time support ticket.  In my email to them I listed everything I had tried, everything I had observed.  The response, as usual, appeared they didn't read a word of it as it told me to do all that I had already done.

I was concerned that a drive had failed, but I had no indication.  I had a working email notification system configured on the unit and had never received a message.  No drive light indicated an error drive.  In panic, I ordered a new Drobo 5N but wanted to leave it as a last resort.

I reached the last resort stage, and after following all preparation instructions, finally moved my drives to the new Drobo.  It displayed the exact same boot sequence (and loop).

I came across some discussion of slot flushing, and I had not performed this step.  I put the drives back into my original Drobo, and step by step did a slot flush on each drive.  Each flush worked as documented.  But when I reached the 4th drive, it did not.  I actually exhibited the sequence I had been seeing all along, eventually turning to a solid orange power light.  

This made me believe I had to have a faulty drive.  So a quick trip to the store and came back with a replacement drive of same size and spec.  Having successfully slot flushed the other four drives, and with the device powered down, I inserted the new drive, made sure all were secure in their slots and powered up.  

Finally a normal boot.  Finally the Drobo Dashboard software saw my Drobo.  I should note that was another symptom.  No access to the device using the dashboard unless I removed all drives and directory connected the network cable to my laptop.  

Now the dashboard is reporting 93 hours to restore.  But as the documentation states, I can already access the data stored on the Drobo, I just cannot write to it (and that is fine).  I have a feeling the actual restoration of the new drive will take less time but I really don't care because I have my data back.  

For a while there I was not happy with Drobo.  The whole reason for this large investment was to protect my data, and now I was in a state of no access to my data, and no help from them at all.  Even though I had registered my Drobo after purchase it was out of warranty and I guess they don't care to read what someone writes and instead just send back boilerplate 'make sure you drives are all connected' type stuff.

I had never found an exact description and solution to the problem I experienced when searching, so I wanted to document it in case anyone else runs into the same situation as myself.

I wish I knew why I was not given any indication I had a bad drive.  That would have saved an enormous amount of time and money.  

Be cautious whenever troubleshooting your Drobo.  The last thing you want to do is mistakenly do something that will cause it to wipe your data.

Here is an example of the slot flush procedure.  I am not saying 'do it' but since it gave me the clue to the solution I would like to offer a link:

https://myproducts.drobo.com/article/AA-01429