[mpls-linux-general] Help : mpls routing examples/pointers

[Murthy S. A. <msa...@cs...>]

I am trying to come up with various LSPs between machines 
A(LER),B(LSR),C(LSR), D(LER) in my lab. i.e. 
A-D, A-B-D, A-C-D,A-B-C-D,A-C-B-D etc.
I have looked through the examples in mpls-linux-1.1/utils/README and
some other  docs on the web, but still cannot figure out how to setup the 
commands. 

My problem is, on an LSR , How to associate a different outgoing 
label with each incoming label ? i.e. if machine C receives packets with 
label 'LA' from A and 'LB' from B, how to replace 'LA' with 'LA2'(say) and 
'LB' with 'LB2'(say) on their way out to D. (None of the examples i 
came across, as I understand them, seem to address this particular issue)

some background : I have successfully setup an LSP between two machines
using mplsadm. However, all that happens here is that a label is 'push'ed 
on one machine and is 'pop'ped on the other. there is no 'swapping' of 
labels. now, I am trying to extend this into a 4-machine network with 
various paths as mentioned above. 

any examples/help will be greatly appreciated.

Thanks in advance
Murthy Andukuri