For those also struggling with the raid1 set up and associated firmware upgrade issues, I have the following “lessons learned” feedback from my efforts to resolve this problem.
The case put to WD Support: firmware update 5.20.113 caused a series of problems including degraded raid ; not able to roll back or update to latest firmware 5.21.104; all system and disk tests came back GOOD but red LED light and caution remained; full factory reset didn’t solve the problem but noticed that I couldn’t create shared folders or load files onto the drives via USB or LAN; 4 sec reset never work nor multiple reboots; waited for the call back from WD Support and pondered my next move.
Firstly, I had already backed up my data on an external USB drive so avoided a total disaster.
Finally, I removed both drives (having previously replaced the CR2032 battery in the device) and replaced what I believed to be a good drive into 2nd bay and restarted the unit.
Shock, surprise: the firmware automatically updated successfully and setting the drive to JBOS all went well. Keep in mind that all the diagnostics provided with the ex2 ultra said both drives were good and no errors found. NOTE: MY HOUR LONG DISCUSSION WITH WD SUPPORT AGENT CONCLUDED THE ENCLOSURE WAS FAULTY AND OFFERED A DISCOUNT FOR A NEW ONE!
Files now loading and shares being set up just fine. Bought a new WD 6TB RED drive and inserted into first bay. Migration took about 12 hours but when smoothly and all is back to where it should have been. All LEDs are blue and the box is busy but quiet.
Asked WD Support about diagnostic tools that I could download to my laptop to test the replaced drive in a docking station. He suggested using MS Disk Management…oops, sorry, it’s LINUX, not Windows that runs ex2 ultra. No, can only use the tools that come with the unit…the ones that constantly said all was good with the drives and the system.
Asked why no reset button or power off feature: sorry, not designed for either of these features. You must hibernate and unplug to turn off completely and re plug to restart.
I have had this unit for 4-1/2 years and now running with the 4th and 5th drives having dumped two as not usable and one as a HD attached via a docking station for one more back up.
It’s my hope that his feedback to other users may be helpful. I have many WD products but realise that I must keep seriously irreplaceable data backed up on external drives and now some are on icloud.