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Re: ifconfig(8) - a tale of two states



>          media: IEEE802.11 OFDM54 monitor (OFDM54 mode 11g monitor)
>          status: active
>          inet 192.168.0.1/24 broadcast 192.168.0.255 flags 0x4<DETACHED>

> We claim that the media is active but the address is detached and
> there is no SSID!

> WTF BBQ!

Is this inconsistent?  I don't know enough about 802.11, but it seems
plausible, at least, to me that the radio could be on (media active)
without the interface having an SSID...particularly for passive traffic
snooping.  (I can't comment on the detached address; I have no
experience with that flag and what its semantics may be.  The ordinary
English meaning of "detached" sounds to me more like the address not
being on the interface at all, so it clearly means something else.)

> [...], but MONITOR is just read only.  It cannot send.  As such any
> addresses on the interface are useless.

I disagree.  While receive-only is much rarer than two-way (or,
probably, even than send-only), it does have its uses.  And there are
even a few uses for addresses on interfaces without either sending *or*
receiving.  While most of them are better addressed by making the
address an alias on lo0, I have no trouble imagining a case where
leaving the address on the interface even during a relatively temporary
period of inactivity is more convenient than moving it elsewhere.

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