RB2011 is not working with APC. Its maybe HW issue?
Several weeks ago I started to work up a table comparing a RB493G (with USB 3.3VDC power jumper soldered in) vs. the RB2011, but never posted it. The reason I never published my results was because I felt using a modified Routerboard in the comparison test was probably unfair even though the modification I came up with to bring the RB493G USB port "alive" is an extremely simple/minor modification.
So, after waiting and hoping the RB2011 APC UPS issue would get resolved in the last few ROS updates or Routerboard firmware updates along with seeing your post on the topic I've decided to share what my tests have shown.
I tested five different APC UPS models with both Routerboards running the current ROS version at the time of I think 5.19 or v5.21. The APC UPS models I tested were an older APC 500VA, a slightly newer APC 550VA, a new APC 550G, an older APC 1500XS with the LCD screen and finally a new APC 1500XS with the LCD screen.
The results were the RB493G USB port was able to read all five APC UPSs I tested without any problem. The RB2011 was only able to read the older APC 1500XS UPS LCD and the new APC 1500XS UPS LCD models.
In my opinion the RB2011 hardware is fine as it can read both old and new APC 1500XS LCD UPSs. So, we can conclude the RB2011 USB port appears to work as designed.
The argument that APC has made their "code" incompatible with ROS in their new UPSs is proven false as the RB493G reads all the UPSs tested without any problem. So, it is my opinion the RB2011 APC UPS problems are firmware or ROS related specifically to the RB2011.
Hopefully the guys at MikroTik will resolve the RB2011 APC UPS problem soon or release a newer RB2011 Routerboard with all GigE ports, two SFP ports, a much faster CPU and a USB port that can read all the APC UPSs like the RB493G !!!!