Hi - We have a filer installed over a year ago now. When we had it installed we assumed that it was done properly as this is our first NetApp device. After getting warning errors from the filer and further reading - investigating I believe that the SAS wiring is incorrect.
Below is the current wiring of our production NetApp.
From reading the ACP is wired correctly - however when i run the config advisor I get the following errors. Which I believe the sas wiring is incorrect.
i've used colours to illustrate the 'loop' to each controller. You can see that IOMA from the shelf has a path (blue) to each controller and IOMB has a path (Red) to each controller.
As stated above just remember circle->square, circle->square and you'll be good. eg follow the blue path from Controller 1 (circle), to shelf 1 IOMA (Square) from Shelf 1 IOMA (Circle) to Controller 2 (Square).
The same is true when you follow the nred path from Controller 2
0a & 0b are the opposite way round on my diagram (0a= circle)
Your picture shows a 3000 series controller. The 2240 series has "Circle" and "Square" icons on the the controller itself. If you cable a 2240 the way your picture shows, config advisor WILL still complain. While technically it would work and is fully HA multipathed.
If you are looking at the back of a 2240, Square is on the left and circle is on the right. In your drawing you have a circle port going to a circle port and technically not following the circle -> square rule.
On a 2240, circles always go to squares, even the bottom (shelft back to the controller) connections.