Question : ntp synchronization

Headquater router 2811 using PST and branch router 2811 using EST. I configured to synchronize time and pc and phones will use PST time from HQ. Here is my configuration. How could I verify branch router get PST? PC connected branch router still EST.

HQ
scheduler allocate 20000 1000
ntp master 2
ntp peer 10.10.11.40
ntp peer 10.10.11.20

HQ#sh ntp status
Clock is synchronized, stratum 2, reference is 127.127.7.1
nominal freq is 250.0000 Hz, actual freq is 250.0000 Hz, precision is 2**18
reference time is CFD9EB82.4A2B5B03 (10:01:54.289 PDT Sat Jul 3 2010)
clock offset is 0.0000 msec, root delay is 0.00 msec
root dispersion is 0.02 msec, peer dispersion is 0.02 msec

HQ#sh ntp associations
      address         ref clock     st  when  poll reach  delay  offset    disp
 ~10.10.11.40      0.0.0.0          16     -  1024    0     0.0    0.00  16000.
*~127.127.7.1      .LOCL.            1     3    64  377     0.0    0.00     0.0
 ~10.10.11.20      10.10.30.1        3  8773  1024    0     8.7    0.06  16000.
 * master (synced), # master (unsynced), + selected, - candidate, ~ configured

Branch Router
scheduler allocate 20000 1000
ntp clock-period 17179963
ntp peer 10.10.11.40
ntp server 10.10.30.1
ntp peer 10.10.11.20

SRST-BR1#sh ntp status
Clock is unsynchronized, stratum 16, no reference clock
nominal freq is 250.0000 Hz, actual freq is 249.9986 Hz, precision is 2**18
reference time is CFD9C8E5.183BBE1A (10:34:13.094 EDT Sat Jul 3 2010)
clock offset is 0.0000 msec, root delay is 8.83 msec
root dispersion is 0.11 msec, peer dispersion is 0.06 msec
SRST-BR1#

SRST-BR1#show ntp associations

      address         ref clock     st  when  poll reach  delay  offset    disp
 ~10.10.11.40      127.127.7.1       2  8983    64    0     8.7    0.00  16000.
 ~10.10.30.1       127.127.7.1       2  9181    64    0     8.8   -0.01  16000.
 ~10.10.11.20      0.0.0.0          16     -    64    0     0.0    0.00  16000.
 * master (synced), # master (unsynced), + selected, - candidate, ~ configured
SRST-BR1#

Answer : ntp synchronization

rfc1180 is right:  You will need to configure the timezone for each router (and also the timezone for each PC and phone) to ensure it displays correctly.

NTP distribute a time-code relative to UTC (previously known as GMT), and does not transmit time zone or daylight savings time information.

One thing I noticed:  You have three NTP peers: HQ is one, and 10.10.11.20 and 10.10.11.40 are the two others.  However, you also configured the last two as peers to the branch router.  But is seems that there is clock-discrepancies between the devices, and therefore not one of them is acceptable to the branch router.

If you cannot source your clock from a valid source (such as a GPS time receiver or an Internet based server) I'd suggest that you choose one source as the master, and sync all others to that device.  For redundancy, you can implement a second server, but just ensure that the second server also sync from the master, and when the master falls away, that it have a less-preferable stratum than the master, but higher than 15. ('ntp master 5' or so should work).
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