Cisco >224.0/3 problems..

Mon Feb 1 19:07:06 UTC 1999

Hello all,

  Ran into a problem, thought maybe someone else has run into this and
knows of a "fix", if this is intentional or what not.

  It seems that Cisco IOS has a problem dealing with addresses above
224.0.0.0/3.

  This came up in an e-mail with Paul Vixie about MAPS RBL, where I asked
him why 224+ wasn't filtered.  The reply was: IOS ignores it.  GateD likes
it, IOS doesn't.

  I'm finding that IOS isn't propagating routes, etc., (nor will it even
seem to *recognize*) address space above 224.

  To wit:

As a /3:
bordercore1.chi(config)#ip route 224.0.0.0 224.0.0.0 Null0
%Invalid destination prefix

/8, close to the end of address space:
bordercore1.chi(config)#ip route 252.0.0.0 255.0.0.0 null0
%Invalid destination prefix

As a /24:
bordercore1.chi(config)#ip route 225.0.0.0 255.255.255.0 Null0
%Invalid destination prefix

bordercore1.chi(config)#ip route 230.0.0.0 255.255.255.0 Null0
%Invalid destination prefix

It's not Null0:

bordercore1.chi(config)#ip route 234.128.230.123 255.255.255.255 h9/0
%Invalid destination prefix

bordercore1.chi(config)#ip route 241.102.34.93 255.255.255.255 atm4/0  
%Invalid destination prefix

I know this is all "multicast" space, but considering classless routing
and CIDR, shouldn't this space be usable and able to be manipulated ?

-jamie
-- 
jamie rishaw (efnet:gavroche) @ AIS / Exodus
"I want peace on earth and goodwill towards men."
"We are the United States Government.  We don't do that sort of thing."
  --sneakers