But it's interesting to note GRE is not included in it. From the EXOS User Guide:
"GRE tunnels are IP tunnels which require L3 Function. L3 features are supported with EDGE license and above. All of the supported platforms' default license is EDGE or above, which include L3 features. In a stack all of the nodes must be GRE capable. For GRE in a stack, all stack nodes must be GRE hardware capable."