[Dump] A Babel experiment at funkfeuer.at

Harald Geyer (spam-protected)
Tue Dec 23 15:19:07 CET 2008


>   babel -D -g 33123 -k 20
> 
> I suggest you use port 33123 for the local interface, just like we do, so
> that our tools (see below) can interoperate.

Ok. Perhaps this port should be recommended in the man page also ...
 
> > monitor it via "telnet ::1 2222" - do you recommend something else
> > then telnet?
> 
> Yes.  Log into your OpenWRT box using
> 
>   ssh -L 33123:ip6-localhost:33123 ...
> 
> Then, you can telnet ::1 33123 on the machine from which you logged in,
> which means you can use the nice local telnet rather than the limited
> version included in OpenWRT.

Hmm, I should have thought about this myself...
Anyway: It doesn't work either. On the router I get messages
"channel 3: open failed: connect failed:" whenever I try to start telnet
and telnet says:

| Connected to ip6-localhost.
| Escape character is '^]'.
| Connection closed by foreign host.

This is the same whether I connect to the routers v4 or v6 Address.
(General ssh over v6 works in both directions.)

> The interface is actually not designed for human beings, it's designed for
> a GUI.  Two students of mine have been working on the GUI for the last six
> months, their current version is available by doing
> 
>   darcs get http://www.pps.jussieu.fr/~jch/software/repos/BabelTool
> 
> Yes, the code is a mess, but the algorithms are pretty sweet.  (We'll try
> to clean the codebase up over the next months.) 

Hm, does it work with free java? (ie packages included in lenny-main)

> The port is hard-wired to 33123.
 
Hm, makes it difficult to connect to several routers at the same time...

> > Ok, I used this as a start. Next I'll play with non default
> > metrics. Especially tunnels should be expensive instead of having the
> > same link cost as a cable ... 
> 
> Yep.  I'm thinking of measuring RTT times and doing that automatically, but
> it's pretty low on my TODO list.

Hm, that might be a nice idea. But typically you don't want to use tunnels,
so I'll just give them link costs high enough that they don't get used
unless there is no other alternative...

> > So far I have only played with sit tunnels, which works fine.
> 
> That's a bad idea, since SIT cannot carry IPv4, so it means that all the
> infrastructure will need changing if you ever decide to switch to hybrid
> routing.  I strongly recommend GRE, which is portable and able to carry
> multiple protocols.

I'll keep that in mind. But if we ever use babel to route real traffic
(ideas which already brought some heated mails into my inbox) then the
tunnels need to go away: routing babel over tunnel over olsr would
make a complete mess - there is no way to get compatible link costs
for the tunnels. Building tunnels within one mesh to build an other
mesh is a hack not infratructure.

> > I suggest that we start with two tunnels between your site and Vienna.
> 
> No can do -- we're using OpenVPN (negotiated with our sysadmin), and
> I really don't feel like going through the negotiations again.  I'll get in
> touch with you through private mail.

I see. openvpn should be ok. Perhaps keep the people that are on personal
CC now involved in our tunnel negotiation ...

Thanks for your help,
Harald






More information about the Dump mailing list