I am trying to adjust my clock with daylight savings time and realized that it was time to set up ntp on my home lan. LAN is a 192.168.2.x network behind a masquerading firewall that is connected to Time Warner cable network. On the network there are 5 machines (4 of them Red Hat Linux 7.0 and 1 with RHL7.1-qa0328 on it. On the 7.0 machines I get the following: root:{smooge}# ntpdate ntp2.usno.navy.mil 1 Apr 15:19:05 ntpdate[6342]: adjust time server 192.5.41.209 offset 0.093178 sec root:{smooge}# ntpdate -d -v ntp2.usno.navy.mil 1 Apr 15:22:26 ntpdate[6346]: ntpdate 4.0.99j Wed Aug 23 13:11:25 EDT 2000 (1) transmit(192.5.41.209) receive(192.5.41.209) transmit(192.5.41.209) receive(192.5.41.209) transmit(192.5.41.209) receive(192.5.41.209) transmit(192.5.41.209) receive(192.5.41.209) transmit(192.5.41.209) server 192.5.41.209, port 123 stratum 1, precision -17, leap 00, trust 000 refid [USNO], delay 0.12823, dispersion 0.00041 transmitted 4, in filter 4 reference time: be71fe72.a6589000 Sun, Apr 1 2001 15:22:26.649 originate timestamp: be71fe72.b085b000 Sun, Apr 1 2001 15:22:26.689 transmit timestamp: be71fe72.a43d9a95 Sun, Apr 1 2001 15:22:26.641 filter delay: 0.12880 0.12936 0.12823 0.12834 0.00000 0.00000 0.00000 0.00000 filter offset: -0.00444 -0.00309 -0.00409 -0.00367 0.000000 0.000000 0.000000 0.000000 delay 0.12823, dispersion 0.00041 offset -0.004094 1 Apr 15:22:26 ntpdate[6346]: adjust time server 192.5.41.209 offset -0.004094 sec However on the 7.1 box I get the following: root:{RPMS}# ntpdate -v -v ntp2.usno.navy.mil 1 Apr 15:14:25 ntpdate[1461]: ntpdate 4.0.99k Mon Mar 5 12:08:05 EST 2001 (1) 1 Apr 15:14:29 ntpdate[1461]: no server suitable for synchronization found HOWEVER on the 7.1 box if I go into debug mode it seems to work root:{RPMS}# ntpdate -d -v ntp2.usno.navy.mil 1 Apr 15:17:41 ntpdate[1489]: ntpdate 4.0.99k Mon Mar 5 12:08:05 EST 2001 (1) transmit(192.5.41.209) receive(192.5.41.209) transmit(192.5.41.209) receive(192.5.41.209) transmit(192.5.41.209) receive(192.5.41.209) transmit(192.5.41.209) receive(192.5.41.209) transmit(192.5.41.209) server 192.5.41.209, port 123 stratum 1, precision -16, leap 00, trust 000 refid [USNO], delay 0.13148, dispersion 0.00220 transmitted 4, in filter 4 reference time: be71fe87.4f835000 Sun, Apr 1 2001 15:22:47.310 originate timestamp: be71fe93.50b0d000 Sun, Apr 1 2001 15:22:59.315 transmit timestamp: be71fd55.f1ed4a1a Sun, Apr 1 2001 15:17:41.945 filter delay: 0.13364 0.13412 0.13148 0.13965 0.00000 0.00000 0.00000 0.00000 filter offset: 317.3146 317.3154 317.3171 317.3129 0.000000 0.000000 0.000000 0.000000 delay 0.13148, dispersion 0.00220 offset 317.317177 1 Apr 15:17:42 ntpdate[1489]: step time server 192.5.41.209 offset 317.317177 sec
This defect considered MUST-FIX for Florence Gold
I don't think we have really identified the problem: [pbrown@dionysus pbrown]$ sudo ntpdate -d ntp2.usno.navy.mil 2 Apr 10:07:16 ntpdate[20497]: ntpdate 4.0.99k Mon Mar 5 12:08:05 EST 2001 (1)transmit(192.5.41.209) transmit(192.5.41.209) transmit(192.5.41.209) transmit(192.5.41.209) transmit(192.5.41.209) server 192.5.41.209, port 123 stratum 0, precision 0, leap 00, trust 000 refid [0.0.0.0], delay 0.00000, dispersion 64.00000 transmitted 4, in filter 4 reference time: 00000000.00000000 Thu, Feb 7 2036 1:28:16.000 originate timestamp: 00000000.00000000 Thu, Feb 7 2036 1:28:16.000 transmit timestamp: be730617.c38af3e4 Mon, Apr 2 2001 10:07:19.763 filter delay: 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 filter offset: 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 delay 0.00000, dispersion 64.00000 offset 0.000000 2 Apr 10:07:20 ntpdate[20497]: no server suitable for synchronization found I believe this is a firewall issue.
notice the lack of receives. They are getting filtered/firewalled.
now note something definitely not firewalled off: [pbrown@dionysus pbrown]$ sudo ntpdate -d clock.corp.redhat.com 2 Apr 10:25:25 ntpdate[20965]: ntpdate 4.0.99k Mon Mar 5 12:08:05 EST 2001 (1)transmit(207.175.43.182) receive(207.175.43.182) transmit(207.175.43.182) receive(207.175.43.182) transmit(207.175.43.182) receive(207.175.43.182) transmit(207.175.43.182) receive(207.175.43.182) transmit(207.175.43.182) server 207.175.43.182, port 123 stratum 3, precision -17, leap 00, trust 000 refid [152.2.21.1], delay 0.02582, dispersion 0.00000 transmitted 4, in filter 4 reference time: be7309b5.e20f3cb3 Mon, Apr 2 2001 10:22:45.883 originate timestamp: be730a55.93ea704b Mon, Apr 2 2001 10:25:25.577 transmit timestamp: be730a55.945a5fc7 Mon, Apr 2 2001 10:25:25.579 filter delay: 0.02588 0.02583 0.02582 0.02582 0.00000 0.00000 0.00000 0.00000 filter offset: -0.00183 -0.00184 -0.00184 -0.00184 0.000000 0.000000 0.000000 0.000000 delay 0.02582, dispersion 0.00000 offset -0.001841 2 Apr 10:25:25 ntpdate[20965]: adjust time server 207.175.43.182 offset -0.001841 sec Are you sure you have no firewall settings in effect on the 7.1 box at home?