//
// enforce strict segment checking (and turn off gso) to measure probe length
--strict_segments
--ip_version=ipv6
--local_ip=fd::1
--gateway_ip=fd::2
--remote_ip=fd::3


`../common/defaults.sh
 ip -6 route change fd::3 via fd::2 dev tun0 advmss 1000 mtu lock 1460 initcwnd 4
 ethtool -K tun0 gso off tso off
 ../common/set_sysctls.py /proc/sys/net/ipv4/tcp_timestamps=0 \
    /proc/sys/net/ipv4/tcp_syn_retries=3 \
    /proc/sys/net/ipv4/tcp_synack_retries=3 \
    /proc/sys/net/ipv4/tcp_sack=0 \
    /proc/sys/net/ipv4/tcp_dsack=0 \
    /proc/sys/net/ipv4/tcp_frto=0 \
    /proc/sys/net/ipv4/tcp_reordering=3 \
    /proc/sys/net/ipv4/tcp_congestion_control=reno \
    /proc/sys/net/ipv4/tcp_slow_start_after_idle=1 \
    /proc/sys/net/ipv4/tcp_early_retrans=0 \
    /proc/sys/net/ipv4/tcp_recovery=0 \
    /proc/sys/net/ipv4/tcp_ecn=0 \
    /proc/sys/net/ipv4/tcp_fastopen=0 \
    /proc/sys/net/ipv4/tcp_window_scaling=0 \
    /proc/sys/net/ipv4/tcp_rmem="64000 64000 64000" \
    /proc/sys/net/ipv4/tcp_wmem="64000 64000 64000" \
    /proc/sys/net/ipv4/tcp_retries1=3 \
    /proc/sys/net/ipv4/tcp_retries2=3  \
` 

0   socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
+0  setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
+0  bind(3, ..., ...) = 0
+0  listen(3, 1) = 0

//TCP three-way handshake
+0  < S 0:0(0) win 4000 <mss 1000>
+0  > S. 0:0(0) ack 1 <...>

+.1 < . 1:1(0) ack 1 win 4000
+0  accept(3, ..., ...) = 4

// write ten bytes
+0 write(4, ..., 10)=10
+0 > P. 1:11(10) ack 1
+.1 < . 1:1(0) ack 11 win 4000

// read two bytes
+.1 < P. 1:3(2) ack 11 win 4000
+0 > . 11:11(0) ack 3
+.2 read(4,...,1000)=2

//Packetdrill closes connection gracefully
+0 < F. 3:3(0) ack 11 win 4000
+0 > . 11:11(0) ack 4

//Kernel closes connection gracefully
+0 close(4) = 0
+0 > F. 11:11(0) ack 4
+0 < . 4:4(0) ack 12 win 4000