You still only need the ntp server command. Lets say the requirement was to sync the HQ router with the PSTN router and then all other devices sync NTP with the HQ router. On the HQ rtr the only command needed is "ntp server 10.10.100.2". The rest would point to the HQ rtr ip "ntp server 10.10.200.3"
Jason ----- Original Message ----- From: Bill Sent: 06/08/12 04:17 PM To: Jason Murray Subject: Re: [OSL | CCIE_Voice] NTP Master Dilemm Let us say they want the local router to be ntp server or back up Then y Bill On Jun 8, 2012, at 2:56 PM, "Jason Murray" < murr...@usa.com > wrote: Do not use ntp master on any of your routers. The only command that is needed is the ntp server command. Even if you want one of your routers to be the NTP server you dont need the ntp master command. Jason ----- Original Message ----- From: Mann Chaddha Sent: 06/08/12 12:19 PM To: ccie_voice@onlinestudylist.com Subject: [OSL | CCIE_Voice] NTP Master Dilemma Hi Experts I am due for my next Lab attempt in 5 days time. I so far have never been able to get marks for NTP section. So I ask this question to the forum that if someone has ever scored 100% in the Infra Section (without breaking the NDA of course) , can they lend some light on this innocuous looking command, ntp master. Here are some finding from my POD: [10.10.100.1 = PSTN RTR & 10.10.110.1=HQ RTR] 1. With NTP Master Command R1: ntp source Loopback0 ntp master 10 ntp server 10.10.100.1 source Loopback0 ! clock timezone PST -8 clock summer-time PDT recurring R2: ntp server 10.10.110.1 Show commands: R1: HQ-R1#sh ntp status Clock is unsynchronized, stratum 16, no reference clock nominal freq is 250.0000 Hz, actual freq is 250.0008 Hz, precision is 2**24 reference time is D37C1C18.AAB00668 (23:37:12.666 PDT Thu Jun 7 2012) clock offset is 0.0000 msec, root delay is 0.00 msec root dispersion is 0.00 msec, peer dispersion is 0.00 msec loopfilter state is 'CTRL' (Normal Controlled Loop), drift is -0.000003145 s/s system poll interval is 64, last update was 384 sec ago. HQ-R1# HQ-R1# HQ-R1#sh ntp ass HQ-R1#sh ntp associations address ref clock st when poll reach delay offset disp x~127.127.1.1 .LOCL. 9 16 16 377 0.000 0.000 0.240 x~10.10.100.1 .LOCL. 1 50 64 377 0.000 13194.1 3.293 * sys.peer, # selected, + candidate, - outlyer, x falseticker, ~ configured R2: BR1-R2#sh ntp status Clock is unsynchronized, stratum 16, no reference clock nominal freq is 250.0000 Hz, actual freq is 249.9990 Hz, precision is 2**24 reference time is 00000000.00000000 (16:00:00.000 PST Wed Dec 31 1899) clock offset is 0.0000 msec, root delay is 0.00 msec root dispersion is 0.01 msec, peer dispersion is 0.00 msec loopfilter state is 'CTRL' (Normal Controlled Loop), drift is 0.000003885 s/s system poll interval is 64, never updated. BR1-R2# BR1-R2#sh ntp ass address ref clock st when poll reach delay offset disp ~10.10.110.1 73.78.73.84 16 55 64 300 0.000 1325166 944.35 * sys.peer, # selected, + candidate, - outlyer, x falseticker, ~ configured CUCM: admin:utils ntp status ntpd (pid 6322) is running... remote refid st t when poll reach delay offset jitter ============================================================================== *127.127.1.0 LOCAL(0) 10 l 63 64 377 0.000 0.000 0.001 10.10.110.1 .INIT. 16 u 64 128 370 1.897 -2.990 1087693 synchronised to local net at stratum 11 time correct to within 12 ms polling server every 512 s Current time in UTC is : Fri Jun 8 06:22:22 UTC 2012 Current time in America/Los_Angeles is : Thu Jun 7 23:22:22 PDT 2012 ------------------------------------------------------------------------------ Scenario 2: Without NTP Master Command. ------------------------------------------------------------------------------ R1: ntp source Loopback0 ntp server 10.10.100.1 source Loopback0 ! clock timezone PST -8 clock summer-time PDT recurring R2: BR1-R2#r | s ntp ntp server 10.10.110.1 Show Commands: HQ-R1#sh ntp status Clock is synchronized, stratum 2, reference is 10.10.100.1 nominal freq is 250.0000 Hz, actual freq is 250.0008 Hz, precision is 2**24 reference time is D37C21AB.D80D6753 (00:00:59.843 PDT Fri Jun 8 2012) clock offset is -0.0078 msec, root delay is 0.00 msec root dispersion is 0.01 msec, peer dispersion is 0.00 msec loopfilter state is 'CTRL' (Normal Controlled Loop), drift is -0.000003182 s/s system poll interval is 64, last update was 264 sec ago. HQ-R1# HQ-R1#sh ntp ass address ref clock st when poll reach delay offset disp *~10.10.100.1 .LOCL. 1 11 64 377 0.000 -7.866 2.813 * sys.peer, # selected, + candidate, - outlyer, x falseticker, ~ configured HQ-R1#sh ntp ass d 10.10.100.1 configured, our_master, sane, valid, stratum 1 ref ID .LOCL., time D37C229E.73B36D17 (00:05:02.451 PDT Fri Jun 8 2012) our mode client, peer mode server, our poll intvl 64, peer poll intvl 64 root delay 0.00 msec, root disp 0.47, reach 377, sync dist 0.00 delay 0.00 msec, offset -7.8662 msec, dispersion 2.81 precision 2**24, version 4 org time D37C22AE.D47DF91B (00:05:18.830 PDT Fri Jun 8 2012) rec time D37C22AE.D7653258 (00:05:18.841 PDT Fri Jun 8 2012) xmt time D37C22AE.D6E2248F (00:05:18.839 PDT Fri Jun 8 2012) filtdelay = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 filtoffset = -0.01 -0.00 -0.00 -0.00 -0.00 -0.00 -0.00 -0.00 filterror = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 minpoll = 6, maxpoll = 10 BR1-R2#sh ntp s Clock is synchronized, stratum 3, reference is 10.10.110.1 nominal freq is 250.0000 Hz, actual freq is 249.9990 Hz, precision is 2**24 reference time is D37C2310.A8751D42 (00:06:56.658 PDT Fri Jun 8 2012) clock offset is 0.0034 msec, root delay is 0.00 msec root dispersion is 0.96 msec, peer dispersion is 0.93 msec loopfilter state is 'CTRL' (Normal Controlled Loop), drift is 0.000003898 s/s system poll interval is 64, last update was 7 sec ago. BR1-R2# BR1-R2# BR1-R2# BR1-R2#sh ntp ass address ref clock st when poll reach delay offset disp *~10.10.110.1 10.10.100.1 2 11 64 17 0.000 3.472 939.41 * sys.peer, # selected, + candidate, - outlyer, x falseticker, ~ configured admin:utils ntp status ntpd (pid 13103) is running... remote refid st t when poll reach delay offset jitter ============================================================================== 127.127.1.0 LOCAL(0) 10 l 60 64 377 0.000 0.000 0.001 *10.10.110.1 10.10.100.1 2 u 57 64 377 1.718 1.677 5.437 synchronised to NTP server (10.10.110.1) at stratum 3 time correct to within 29 ms polling server every 64 s Current time in UTC is : Fri Jun 8 07:07:22 UTC 2012 Current time in America/Los_Angeles is : Fri Jun 8 00:07:22 PDT 2012 admin: As soon as I apply NTP master command, it breaks my NTP Sync. Am I missing something stupid in here. Please chime in. Thanks Mann _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit http://www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out http://www.PlatinumPlacement.com
_______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com
