[c-nsp] Cross-subnet wake-on-lan (directed broadcast) with 6500s

[Dale W. Carder]

On Dec 5, 2006, at 9:10 AM, Phil Mayers wrote:
[directed broadcasts]
>   You can either have them forwarded in hardware with no filtering, or
> you can have them forwarded in software with filtering

That's my impression, too.  However, I would like to be proved wrong.

>   2. Can people provide concrete details that I can use to argue  
> against
> implementation of either of the directed broadcast options?

Directed broadcasts without packet filtering is a no-go.
Software implementation of ACL's is a no-go.

>   3. Are people aware of any other technical solution which might
> provide this facility? An ability to emit them from the routers via  
> TCL
> perhaps, or some other fiendish way?

If you're going to be forced into this, here's what I think would work
(crappy example off the top of my head, don't try anything like this
without thinking):


int vlan4097
  ip directed-broadcast 153
!
access-list 153 permit udp x.x.x.x y.y.y.255 any eq z
access-list 153 deny udp any any
!
ip access-list extended everythingelse
   permit ip any any
!
class-map match-all wakeonlan
   match access-group 153
class-map match-all default
   match access-group name everythingelse
!
mls qos
!
policy-map control-plane-in
   class wakeonlan
    police cir 32000 bc 32000 be 32000 conform-action transmit exceed- 
action drop violate-action drop
   class default
    police cir 100000000 bc 640000 be 640000 conform-action transmit  
exceed-action drop
!
control-plane
!
service-policy input control-plane-in


Dale

----------------------------------
Dale W. Carder - Network Engineer
University of Wisconsin at Madison
http://net.doit.wisc.edu/~dwcarder