[ 1563.996182][T18720] gre: GRE over IPv4 demultiplexer driver
[ 1564.486710][T18743] ip_gre: GRE over IPv4 tunneling driver
[ 1580.266312][T19314] ip6_gre: GRE over IPv6 tunneling driver
[ 1585.811469][T19563] ping (19563) used greatest stack depth: 23072 bytes left
[ 1590.697582][    C3] ip6_tunnel: tep0 xmit: Local address not yet configured!
[ 1592.680506][    C2] ip6_tunnel: tep0 xmit: Local address not yet configured!
[ 1594.537514][    C2] ip6_tunnel: tep0 xmit: Local address not yet configured!
[ 1596.520512][    C3] ip6_tunnel: tep0 xmit: Local address not yet configured!