==== 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      280782728     2244.018  100.00% 
Conn:   1 Mbps:     2244.018 Peak Mbps:     2244.018 Avg Mbps:     2244.018
        2001      288181904     2305.455  100.00% 
Conn:   1 Mbps:     2305.455 Peak Mbps:     2305.455 Avg Mbps:     2305.455
        3001      272235568     2177.885  100.00% 
Conn:   1 Mbps:     2177.885 Peak Mbps:     2305.455 Avg Mbps:     2177.885
        4002      288358400     2306.867  100.00% 
Conn:   1 Mbps:     2306.867 Peak Mbps:     2306.867 Avg Mbps:     2306.867
        5002      270958976     2167.672  100.00% 
Conn:   1 Mbps:     2167.672 Peak Mbps:     2306.867 Avg Mbps:     2167.672
--- fc00:0:0:1::20 tcpbench statistics ---
1687326272 bytes sent over 6.002 seconds
bandwidth min/avg/max/std-dev = 2167.672/2240.379/2306.867/59.767 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
      21     32768         0 
DISABLED