Hello Rene,
I have configured a lab connecting three switches on gns3 (SW1,SW2 and SW3). SW1 is the Root switch. They are connected like this:
SW1(e1/3-DP)>>>SW2(e1/3-RP)
SW1(e3/0-DP)>>>SW3(e3/2-RP)
SW2(e3/0-DP)>>>SW3(e3/3-ALT/BLK)
The issue is that as soon as i admin down the port on SW3(e3/2-RP), the other port e3/3 becomes the new RP. This is expected. But when i bring back the port up on SW3(e3/2), the port doesn’t becomes automatically RP again, because its far end device port SW1 (e3/0) is going into err-disabled state, essentially the moment that i admined down the port on SW3(e3/2). Hence, in order e3/2 of SW3 reclaim again the RP role, i have to manually bounce the interface e3/0 of SW1. After that e3/0 of SW1 becomes UP, and e3/2 of SW3 becomes RP again. Is this expected behavior? Thank you in advance.