[Click] Not routing via Click

[Bow-Nan Cheng]

Hi Douglas,

Thanks for your quick response. I tried running tcpdump on my wireless 
interface on all the machines (tcpdump -i eth1). Then I try pinging again 
from A to D

On all the nodes that A sees (B and C), its dumping an:

> arp who-has D tell A

with D and A replaced with their actual IP addresses. 

There's also random grid packets (0x7fff) being broadcasted from time to 
time. 

Does thie mean that its not actually following the DSDVRouteTable ? Do I 
need to set forwarding on any of the nodes to "1" 
(/proc/sys/net/ipv4/ip_forward) ?

Thanks again

-Bow-Nan

On Wed, 3 Mar 2004, Douglas S. J. De Couto wrote:

> Your tun/tap setup is probably fine, since adjacent nodes have routes 
> to each other.  That means userlevel click is able to send and receive 
> packets to and from the interface.
> 
> When you ping from A to D over the two-hop route, e.g. A-C-D, can you 
> verify the following by using tcpdump on the actual interface (eth0 or 
> whatever)?:
> 
> - A is actually transmitting the outgoing ping packet, with C's 
> ethernet address as the destination
> - C receives the outgoing ping packet
> - C transmits the outgoing ping packet, with D's ethernet address as 
> the destination
> - D receives the outgoing ping packet
> 
> also, do the same for the ping responses from D to A.  The key is to 
> see where the packet is lost.  It may not be getting routed, or D may 
> not be sending the incoming ping to the kernel, therefore no ping 
> response.  Or, the ping response might be getting lost.
> 
> d
> 
> 
> > I'm currently running Click in USERLEVEL with the GRID extensions. I 
> > setup
> > the DSDVroute table as it says on the webpage:
> >
> > http://www.pdos.lcs.mit.edu/grid/software.html
> >
> > and the nodes seem to be finding each other. The actual routing table
> > itself is setting up quite nicely with no problems.
> >
> > However, it doesn't seem like Click is really doing any of the 
> > forwarding.
> >
> > For example, we have 4 nodes: A, B, C, D
> >
> > General Setup:
> > Node A can ping B and C, but NOT D
> > Nodes B and C both can ping D AND A
> >
> > After setting DSDV up utilizing the perl script 
> > /conf/make-dsdv-config.pl:
> >
> > The route table for A says it can reach B and C in 1 hop and D in 2 
> > hops.
> > Looks good so far.
> >
> > However, when I try pinging D from A, it still says the host is
> > "unreachable".
> >
> --
> Douglas S. J. De Couto    <decouto at csail.mit.edu>
> 

-- 
Bow-Nan Cheng
Senior Web Developer
Nanwob Solutions
Email: bcheng at nanwob.net
Mobile: (201) 563-3875
http://www.nanwob.net