to Markus Stumpf <>
  > > Btw: There is another solution to this problem.
  > > ifconfig supports on most platforms (at least with some minor patches)
  > > "alias names". Thus your host can have more than one IP address
  > > and you can start different httpds for different aliases.

you answered
  > This is not an acceptable solution.  
  > Assigning more than one IP address to hosts (which are not gateways
  > or routers between different physical networks) is an irresponsible
  > use of a consumable resource. IMHO.

I appreciate the concern very much (and while running a local registry
I worked a lot to help avoid wasting of both address space and routing table
size), but there are cases in which assigning multiple addresses are 
perfectly OK;  for example

- if you actually would otherwise pay the price to run an additional interface
  or box (well, first of all I would think that multi-homed hosts OK even
  if they don't forward packets between different physical networks)

- if someone is using private address space (RFC 1597 - do I need my asbestos
  suit?) and adds unique addresses for hosts that are externally visible
  (in particular if the consumed unique address space is densely populated,
  which can be achieved e.g. by distributing host routes to all routers
  on the internal paths to the public network)

- if the address space used for secondary addresses is densely populated
  and routes aggregate well

- temporarily (e.g. to help while renumbering... - and note: if only a small
  percentage of all your hosts gets external connectivety, renumbering the
  externally visible secondary addresses can hurt much less than the traditional
  renumber all of the primary addresses game)

I apologize for abusing the URI and HTTP lists with off-topic traffic;
however I think the question raised by Rob is important enough to have
a reply distributed to the same lists.
For discussing this matter in more detail follow up is suggested to
the CIDRD list (whatever it's today).


Ruediger Volk
Universitaet Dortmund, Informatik IRB
D-44221 Dortmund, Germany

E-Mail: rv@Informatik.Uni-Dortmund.DE
Phone:  +49 231 755 4760                 Fax:  +49 231 755 2386

Received on Saturday, 11 February 1995 14:34:59 UTC