This line is indeed the problem. Someone please ask WD software engineers to change this line to:
dfout= df /DataVolume | grep /DataVolume
That will probably fix this for all users and versions.
Why? I’m pretty sure the problem in my case derived from an apt-get upgrade at some point, which changed the df command to only list one of the many mount points for /dev/sda4 - if you’re lucky, that’s /DataVolume, if not, tough luck. However, if you specifically ask for df /DataVolume, it will display that particular mount point and none of the many others, and the rest of the script will work again.
So what I did was to hack the /bin/df command to always list /DataVolume, and the upgrade worked like a charm… but this is not recommended for anyone but the most advanced Linux hackers.
Which is why I went through the ordeal to become a regular user on this forum, just to post the correct solution to this problem: a simple change to a single line in the vendor’s installer script.
That’s the problem with treating the MyCloud as a general-purpose Linux computer, which it is not; it is a consumer product that happens to be built using a particular version of embedded Linux. Tinker with it at your peril, as it says in the warranty notice.
And you found out why you do not do an apt-get on the My Cloud. If you do a forum search for apt-get you will find numerous threads of people bricking their My Cloud or having other problems. We’ve even jokingly suggested that WD put a huge warning to users NOT to do an apt-get on the My Cloud. WD does warn the user when they enable SSH that they could render their My Cloud inoperable if they don’t know what they are doing.
Once you do an apt-get you are modifying the My Cloud from its intended and designed operation. WD probably will not respond to any requests from us users who ask WD to fix something in the WD firmware that was caused by a user who performed an apt-get.
