Four solid red lights, computer can't detect Drobo (during rebuild)

I added a 3 TB drive to replace a 1 TB drive, on a Drobo that was nearly full.

After about 24 hours, with about 27 hours left (according to the dashboard) the Drobo dropped offline. If I disconnect the USB and reconnect, the computer (Windows 7) says that it is an “unknown device”.

Suggestions?[hr]
I can hear disk activity taking place in the Drobo.[hr]
These could be four orange lights …

All’s well that ends well.

I waited several more hours, then unplugged the Drobo, waited a little while, and plugged it back in.

The Drobo went through several iterations of all red, then one red, then went back to green/yellow flashing. The rebuild finished successfully.

Once that one was done, I removed a second 1TB drive and replaced it with a 3TB drive. I left the USB attached, but did not sleep or hibernate the computer. The (second) rebuild completed without issues (about 40 hours).

well done on your rebuilds,

rebuilds can take longer than the stated amount, (and actually will increase in timee, the more data you have and larger you expand).

im not sure why it dropped off, but maybe it was getting very busy and not as quick to respond to dashboard requests.
either way, well done :slight_smile: