==== run-tcpbench6-3-1 ====
rm -f nc.log
nc -6 -v -l -V 41 fc00:0:0:1::41 12345 >/dev/null 2>nc.log &
# Wait until nc is listening.
for  i in `jot 30`; do if fgrep -q Listening nc.log; then break; fi; sleep .1; done
fgrep Listening nc.log
Listening on fc00:0:0:1::41 12345
# Test that path MTU dicovery is working.
tcpbench -6 -t 5 -V 43 -b fc00::43 fc00:0:0:1::41
  elapsed_ms          bytes         mbps   bwidth 
        1000      317103096     2536.825  100.00% 
Conn:   1 Mbps:     2536.825 Peak Mbps:     2536.825 Avg Mbps:     2536.825
        2001      310478632     2483.829  100.00% 
Conn:   1 Mbps:     2483.829 Peak Mbps:     2536.825 Avg Mbps:     2483.829
        3002      329019520     2629.527  100.00% 
Conn:   1 Mbps:     2629.527 Peak Mbps:     2629.527 Avg Mbps:     2629.527
        4003      237243160     1897.945  100.00% 
Conn:   1 Mbps:     1897.945 Peak Mbps:     2629.527 Avg Mbps:     1897.945
        5004      196506640     1570.483  100.00% 
Conn:   1 Mbps:     1570.483 Peak Mbps:     2629.527 Avg Mbps:     1570.483
--- fc00:0:0:1::41 tcpbench statistics ---
1588307072 bytes sent over 6.000 seconds
bandwidth min/avg/max/std-dev = 1570.483/2223.722/2629.527/415.504 Mbps
# path MTU discovery in other rtable does not work in ip6_output()
/sbin/route -T 43 -n get -host -inet6 fc00:0:0:1::41
   route to: fc00:0:0:1::41
destination: fc00::
       mask: ffff:ffff:ffff::
    gateway: ::1
  interface: lo43
 if address: ::1
   priority: 8 (static)
      flags: <UP,GATEWAY,DONE,STATIC>
     use       mtu    expire
      62     32768         0 
DISABLED