setting up vcan (virtual can interface - loopback) in wheezy

README.vcan

# in /etc/modules add
vcan

so the vcan module is loaded at boot

# in /etc/rc.local, add

ip link add dev vcan0 type vcan
ip link set up vcan0

# reboot, ifconfig vcan0 should show:
mah@nwheezy:/etc/udev/rules.d$ /sbin/ifconfig vcan0
vcan0     Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  
          UP RUNNING NOARP  MTU:16  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)