When booting up a Linux server, some multicast packets are sent out. The destination MAC address is 33:33:00:00:00:02.
I wonder if the multicast address is well known? Does it have some special meaning? Is there a well-known multicast MAC address list?
The mapping of IP multicast addresses to MAC multicast addresses is many-to-one, so technically that MAC address could correspond to lots of different IP addresses. However, in this case, the IP address in question is almost certainly ff01::2, which is the all-routers multicast address. The host is probably sending a router solicitation message.
Multicast MAC addresses beginning with 33:33: are all used by IPv6, but you won't find them in the OUI registry because the IETF did not officially register that prefix with the IEEE (it would have meant too many individual OUI values to register).