# modprobe ip_gre
 # ip tu ad gretun mode gre local 10.5.5.5 remote 10.6.6.6 ttl 64 dev eth0
 # ip ad ad dev gretun 10.0.0.3 peer 10.0.0.4/32
 # ip li se dev gretun up
 # ip ro ad 10.6.10.0/24 via 10.0.0.4
 # ip ro ad 10.6.20.0/24 via 10.0.0.4

Line nomor 2: local address interface fisik dan remote address interface fisik

Line nomor 3: interface tunnel address local dan interface tunnel address remote