==== run-tcpbench6-3-1 ====
rm -f nc.log
nc -6 -v -l -V 20 fc00:0:0:1::20 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::20 12345
# Test that path MTU dicovery is working.
tcpbench -6 -t 5 -V 22 -b fc00::22 fc00:0:0:1::20
  elapsed_ms          bytes         mbps   bwidth 
        1001      158660880     1268.019  100.00% 
Conn:   1 Mbps:     1268.019 Peak Mbps:     1268.019 Avg Mbps:     1268.019
        2001      159026136     1272.209  100.00% 
Conn:   1 Mbps:     1272.209 Peak Mbps:     1272.209 Avg Mbps:     1272.209
        3001      163295800     1306.366  100.00% 
Conn:   1 Mbps:     1306.366 Peak Mbps:     1306.366 Avg Mbps:     1306.366
        4001      154656248     1238.488  100.00% 
Conn:   1 Mbps:     1238.488 Peak Mbps:     1306.366 Avg Mbps:     1238.488
        5006      156617928     1246.710  100.00% 
Conn:   1 Mbps:     1246.710 Peak Mbps:     1306.366 Avg Mbps:     1246.710
--- fc00:0:0:1::20 tcpbench statistics ---
946109472 bytes sent over 5.999 seconds
bandwidth min/avg/max/std-dev = 1238.488/1266.359/1306.366/23.666 Mbps
# path MTU discovery in other rtable does not work in ip6_output()
/sbin/route -T 22 -n get -host -inet6 fc00:0:0:1::20
   route to: fc00:0:0:1::20
destination: fc00::
       mask: ffff:ffff:ffff::
    gateway: ::1
  interface: lo22
 if address: ::1
   priority: 8 (static)
      flags: <UP,GATEWAY,DONE,STATIC>
     use       mtu    expire
      18     32768         0 
DISABLED