I have that same output:
WDmycloud# hdparm -J /dev/sda
/dev/sda:
wdidle3 = 300 secs (or 13.8 secs for older drives)
So what does this mean?
…so having only very recently realised that my device (WD Cloud 1st Gen) is impacted by this bug, and only once I started using HD Sentinel to monitor it:
I am most grateful that I dug out this thread, managed to install idle3ctl yesterday evening - one link above is not valid anymore but I did manage to source this armhf.deb file from elsewhere - and managed to change the timer on this HDD accordingly.
FWIW: my Load Cycle Count (SMART #193) reached nearly 6M - not bad (and quite scary either!) for ~9 year old device that runs 24/7, isn’t it?
What kind-of accelerated my actions were other SMART values of this HDD that started changing: Read Error Rate (#01) & Spin-Up Time (#03) that suddenly jumped a bit in the last year - indicating that this HDD might be on its way out soon.
I also managed to buy second device (hardly used by the looks of it - and its HDD’s SMART values as well), and I endeavour to swap the HDD to the larger one (10-14TB) at some stage in the future once this one eventually fails.
→ I did also spot that HDD firmware revision on the second device was newer (82.00A82 as opposed to 80.00A80 on mine) - and so were its timer settings either (300 seconds as opposed to 8 seconds on mine).
Needless to say all stuff’s backed up as needed.
