Thank you for contacting NVIDIA Mellanox Technologies Technical Support,
My name is Ori and I have respectfully received your request.
Could you please share the exact command you used on the Mellanox?
Just to make sure - The switch that you are trying to append the route map + community is the Mellanox?
What the end goal is?
Are you willing to add append specific community attribute to the NLRI announced by Mellanox to other peers or whether you want to enforce routing policy on the Mellanox while considering the community attribute populated by other peers?