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When I do

ip route show table all

I see some routes with question marks in them as below.

multicast ???/32 from ???/32 table default proto none iif eth0

They appear to be multicast routes. I don't have any idea how they end up having these funny question marks. Actually I was even wondering if multicast routes shall be added to the routing table at all.

Anyone who could put some light on it?

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