In message <29627.1102368412@munnari.OZ.AU>Robert Elz writes
>No, you're debating a different question.


I don't think so. I'm not even sure if multiple-loopback devices was a
deliberate design decision, or if it predates the functional/semantic
 split of`needs-count' vs. ``needs-flag''.

I've also seen no rationale for multiple loopback devices, given that
a single loopback device can support multiple addresses for a given
family.  Christos guessed at a couple of possible uses, but they make
no technical sense. (Link aggregation, for example, requires so much
additional effort that it makes no sense at all to lump it in with a
loopback device).

The only halfway-legitimate reason I can think of is multiple distinct
MTUs on loopback interfaces; and I'm not even sure that works.  And I
know the dynamic MTU-adjustment has some hairy gotchas.