> [mrouted] can't enable multicast routing in kernel (operation not supported)

AFAIK mrouted is independent of whether your routers/backbone support
multicast.  There are protocols for tunneling multicast packets through
non-mbone subnets.  It sounds like the kernel was not compiled to support
multicast and the version of mrouted you have expects it to.  I am very
sure that current BSD stuff is capable of supporting multicast, but it may
not be a standard compile option.

As for whether the network you are on supports multicast, that is another
issue entirely.  I don't think that is so widespread yet.  Router upgrades
cost money.

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