"ifconfig inet 0" vs. DHCP

Chip Salzenberg (chip@perl.org)
Mon, 10 Aug 1998 11:33:55 -0400

A difference between 2.0.x and 2.1.x is that setting a network
interface IP address to 0.0.0.0 actually has the effect of setting it
to _no_ address, i.e. disabling IP.

Now that seems reasonable on the face of it, but I spent a few hours
last night working around it -- because even though you can send DHCP
requests over such an interface, absolutely _no_ incoming packets are
processed, even if the packets are hardware broadcasts and there's an
existing UDP socket ready and waiting.

Now, you may say that you're supposed to set a _real_ IP address for
an interface before you use it, and that's usually true -- but there's
no way to do that here, because the whole point of DHCP is to *get*
the IP address, because you don't know what it is yet.

So, is "0.0.0.0" meaning "no IP" a bug or a feature?

-- 
Chip Salzenberg               - a.k.a. -              <chip@perlsupport.com>
  "Take it to the bridge, Sinbad!  ... drop it in the water ..."  //MST3K


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