Basically, in the "route add" command, you want to specify the _next
hop_ as the address of your nearest neighbor;  you do not want to
specify one of your own addresses.  If you do send the packet to
yourself, you'll receive it, look at the destination address, decide to
send it to yourself as the next hop, and keep on doing this until the
TTL gets to zero!  :)

The "ping -I" command identifies the outgoing interface, which means
you _do_ want to specify your own interface in that case.

You want to find the address of the next hop router, and use that in
your "route add" command.  (You can use traceroute to find the next hop
address.)


On Tue, 25 May 1999, Paul Newhouse wrote:

> On Tue, 25 May 1999 Paul Goyette writes:
> >So, why would you tell your machine that "the next hop to ftp.netbsd.org
> >is reached via my loopback interface?"  You've just told it to send all
> >packets out the lo0, which of course won't do anything at all!
> >
> >On Tue, 25 May 1999, Paul Newhouse wrote:
> >
> >> Sorry, I probably should have included the output from netstat -nr:
> >> 
> >>     Internet:
> >>     Destination        Gateway            Flags     Refs     Use    Mtu  Interface
> >>     default            205.219.89.41      UGS        10   299865      -  de1
> >>     24                 24.1.4.202         UGS         0     3074      -  ne0
> >>     24.1.4.192/27      link#3             UC          0        0      -  ne0
> >>     24.1.4.193         24.1.4.202         UGHS        0        0      -  ne0
> >>     24.1.4.202         00:c0:26:38:80:71  UHL         2        0      -  lo0
> 
> Well, I'm not sure why this looks like this.  Why does:
> 
>   ping -I 24.1.4.202 204.152.184.75
> 
> work?
> 
> >>     127.0.0.1          127.0.0.1          UH          1      198      -  lo0
> >>     172.16.89.40/29    link#1             UC          0        0      -  de0
> >>     172.16.89.42       00:40:05:a0:4e:b2  UHL        19  3233955      -  de0
> >>     204.152.184.75     24.1.4.202         UGHS        0        0      -  ne0
> 
> The system seems to know this is on ne0, guess I'm still mis-understanding something
> about this.
> 
> TIA,
> Paul
> 

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