# Description A tunnel can be use to encapsulate packets in an IP header for transmitting over IP infrastructure. GRE [RFC2784] is a particular tunnelling protocol supported by Cisco routers which can carry different protocols over IPv4. # Iproute2 Commands These commands will create an GRE tunnel with iproute2. ``` ip tunnel add mode gre local remote ttl <0-255> ip link set up ip address add / dev ```