All 4 bays suddenly indicating drive failure

I have an original Drobo, admittedly quite old, but it’s been running steadily for years and I have once had to replace a drive in it. Just today it has suddenly decided to turn up it’s heels and die. It shows all four bays as “Drive Failure”, so I have two questions.

1…What should I do as far as testing it? Dashboard says it doesn’t even exist.

2…If all else fails, how the hell do I get my data off it?

Help would be much appreciated.

hi, if you try switching everything off, including power plug.
and waiting 5mins
and then just try booting up the drobo without any connection cables, eg just the power.

does it do the same thing or does it get a bit further?
if same problem then power off all etc
earth yourself,
and with power still OFF try removing each drive and putting them back in the same place still while OFF (eg to make sure they didnt wiggle out a bit)
and boot up with just drobo and power cable…
if same things, then power all off and remove all drives remembering where they were just in case, and then try to power it on without drives…

sorry for lots of steps to try but if you can post back with as much info as you can it will be helpful for all in case a solution or next steps can be found.