It seems like some device is misbehaving ... advertising is link-local address as IPV6 router ... However, according to ink-local address, it's MAC address should be something like 90:61:cf:2f:XY:WZ ...
I could not find any mapping between this kind of MAC address and manufacturer that would produce incriminating ethernet interface. But that's also true for the device where you observe the list of routers (df:ff:eb:38:38:38).
Hi Mkx, thank you for your reply and your info helped me in determining that the devices that sent all these are the APs and somehow each one advertised RA. But we managed to issue some commands to disable the RA.
Hi Proximus, yes indeed you are absolutely correct and i apologize for my ignorance. Because of your reply i read up all about IPV6 RA and it does help me better now to tackle this issue.
Thank you both as you are amazing! 2 replies and each enlighten me to resolve the issue with the same way.