Here is what I saw:
- Power on, drive lights all solid orange, power light green, cycling quickly through colors.
- Next, side drive lights all go out, power light flashes green, blue lights move from sides to center
- 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:
- 00X0000XXX (x is a illuminated blue led).
- 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: