The easiest way to setup NTP servers is through Cisco ASDM console:
and to Verify that is is working – ssh to your ASA and issue:
ciscoasa# show ntp status – Displays the NTP clock information.
Clock is synchronized, stratum 2, reference is 129.6.15.30 nominal freq is 99.9984 Hz, actual freq is 99.9984 Hz, precision is 2**6 reference time is d97cb143.709fb402 (20:15:15.439 GMT/BDT Mon Aug 17 2015) clock offset is 10.3378 msec, root delay is 85.92 msec root dispersion is 7902.33 msec, peer dispersion is 7892.00 msec
ciscoasa# show ntp associations detail – Displays the configured network time server associations.
192.5.41.41 configured, insane, invalid, unsynced, stratum 16 ref ID 0.0.0.0, time 00000000.00000000 (06:28:16.000 GMT/BST Thu Feb 7 2036) our mode client, peer mode unspec, our poll intvl 64, peer poll intvl 64 root delay 0.00 msec, root disp 0.00, reach 0, sync dist 4302.902 delay 0.00 msec, offset 0.0000 msec, dispersion 16000.00 precision 2**5, version 3 org time 00000000.00000000 (06:28:16.000 GMT/BST Thu Feb 7 2036) rcv time 00000000.00000000 (06:28:16.000 GMT/BST Thu Feb 7 2036) xmt time d97cb2ab.6554faf6 (20:21:15.395 GMT/BDT Mon Aug 17 2015) filtdelay = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 filtoffset = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 filterror = 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 16000.0 129.6.15.30 configured, our_master, sane, valid, stratum 1 ref ID .ACTS., time d97cb28c.1ea28b1a (20:20:44.119 GMT/BDT Mon Aug 17 2015) our mode client, peer mode server, our poll intvl 128, peer poll intvl 128 root delay 0.00 msec, root disp 0.00, reach 377, sync dist 59.219 delay 85.94 msec, offset 11.2877 msec, dispersion 16.25 precision 2**29, version 3 org time d97cb2a3.732dc501 (20:21:07.449 GMT/BDT Mon Aug 17 2015) rcv time d97cb2a3.7b4a5349 (20:21:07.481 GMT/BDT Mon Aug 17 2015) xmt time d97cb2a3.654933bf (20:21:07.395 GMT/BDT Mon Aug 17 2015) filtdelay = 85.94 85.75 85.10 85.17 85.04 85.88 85.92 85.27 filtoffset = 11.29 11.54 12.31 12.24 12.44 11.41 10.34 7.60 filterror = 15.63 16.11 17.09 18.07 19.04 20.02 21.00 21.97
