Hello,
There is a tool to emulate lots of machines in a network based on either
uml, kvm or lxc container techno, this tool is called cloonix and used by
the quagga team (and olsr people).

The version 10 is availlable and may be usefull to test batman big
topologies.

The default machine for the tool is the openwrt but buildroot and debian
machines are very easy to create with a script included in the tool.

See all this at clownix.net.

Vincent Perrier