Check the show ntp peer to see if there's any communication in/out between the two
(beta-7200-controller) #show ntp peer 10.2.2.1
remote 10.63.250.21, local 10.10.10.1
hmode client, pmode mode#255, stratum 3, precision -24
leap 00, refid [18.26.4.105], rootdistance 0.00789, rootdispersion 0.04784
ppoll 10, hpoll 10, keyid 0, version 4, association 6572
reach 377, unreach 0, flash 0x0000, boffset 0.00400, ttl/mode 0
timer 14s, flags system_peer, config, bclient
reference time: d64b5132.5eefbcaa Thu, Dec 5 2013 14:23:30.370
originate timestamp: d64b5794.e6e6ae41 Thu, Dec 5 2013 14:50:44.901
receive timestamp: d64b5794.e71e7d99 Thu, Dec 5 2013 14:50:44.902
transmit timestamp: d64b5794.e6f294dd Thu, Dec 5 2013 14:50:44.902
filter delay: 0.00058 0.00061 0.00055 0.00075
0.00060 0.00069 0.00055 0.00064
filter offset: -0.00055 -0.00054 -0.00043 -0.00043
-0.00038 -0.00016 -0.00026 -0.00028
filter order: 0 1 2 3
4 5 6 7
offset -0.000556, delay 0.00058, error bound 0.12175, filter error 0.00000
time last received: 789s
time until next send: 235s
reachability change: 3174455s
packets sent: 3737
packets received: 3736
bad authentication: 0
bogus origin: 0
duplicate: 0
bad dispersion: 0
bad reference time: 0
candidate order: 6