==== 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 
        1004      195473800     1557.560  100.00% 
Conn:   1 Mbps:     1557.560 Peak Mbps:     1557.560 Avg Mbps:     1557.560
        2001      189751176     1524.106  100.00% 
Conn:   1 Mbps:     1524.106 Peak Mbps:     1557.560 Avg Mbps:     1524.106
        3002      191653192     1531.694  100.00% 
Conn:   1 Mbps:     1531.694 Peak Mbps:     1557.560 Avg Mbps:     1531.694
        4002      212920976     1703.368  100.00% 
Conn:   1 Mbps:     1703.368 Peak Mbps:     1703.368 Avg Mbps:     1703.368
        5003      202944616     1623.557  100.00% 
Conn:   1 Mbps:     1623.557 Peak Mbps:     1703.368 Avg Mbps:     1623.557
--- fc00:0:0:1::41 tcpbench statistics ---
1187270912 bytes sent over 6.001 seconds
bandwidth min/avg/max/std-dev = 1524.106/1588.057/1703.368/67.459 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
      46     32768         0 
DISABLED