[tor-relays] About relay size

[teor]

>>>> A related question is can a relay with only an IPv4 address
>>>> published currently set an IPv6 OutboundBindAddress?
>>> 
>>> Yes. This is useful for IPv6 exits without a fixed IPv6 ORPort address.
>>> 
>>     That's okay, but what if the node is an entry-and-middle node only?
>> 
>     Hmm.  On second thought, it's *not* okay because it means that such a
> node cannot be a middle node because it could only connect to the IPv6
> universe.  Or the man page is wrong about OutboundBindAddress.  Or there
> is something else amiss.

"This option may be used twice, once with an IPv4 address and once with
an IPv6 address"

T