May be someone can help
me find more about GRE keepalive.
i have linux that can work with GRE tunnel. this days i need this linux
to support GRE keepavlive. i cant find any RFC or Cisco document that
have details about the keepalive packet/header format, can any one
knows where can i find more about this issue.
i know the Cisco docs about how to configure the GRE keepavlive
but in this docs no packet format is presented.