WESM zl Management and Configuration Guide WT.01.28 and greater

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Configuring the ProCurve Wireless Edge Services zl Module
Enabling Secure Network Time Protocol (NTP)
■ Peer Poll—the maximum interval between successive messages, in seconds
(always a power of 2 value, such as 8 or 64).
■ Reach—the status of the last eight NTP messages displayed in octal format.
If an NTP packet reaches the resource successfully, the packet is assigned the
value of 1. Otherwise, it is assigned a value of 0. The results for eight packets
make up an eight-digit binary number. That number, expressed in octal format,
is the reach status.
You hope to see 377 for the reach status. This value indicates that all of the last
eight messages have reached the remote NTP device successfully, producing this
binary number: 11111111, which in octal is 377. If the most recent NTP packet
were lost, but the previous seven successful, the reach status would be 376
(11111110).
The lost packet continues to be tracked over the next eight NTP messages. In
this example, if the next three packets were successful, the reach status would
become 370 (11110111). However, if the next three packets were to fail as well,
the reach status would become 360 (11110000).
Note that, as the 0 indicating the lost packet shifts, the reach status decreases no
matter the success of the following packets. Therefore a decreasing value in the
Reach column does not necessary indicate that packets are no longer reaching
the remote resource. For example, just before the status returns to 377, it would
read 177 (01111111).
■ Delay (sec)—the round-trip delay (in seconds) for NTP broadcasts between the
NTP resource and the module
■ Offset (sec)—the calculated offset (in seconds) between the clock on the module
and the NTP resource. The module adjusts its clock to match the server’s time
value. The offset gravitates toward zero over time, but never completely reduces
its offset to zero.
■ Dispersion (sec)—how scattered the time offsets are (in seconds) from an Secure
NTP time server.
To view more detailed information about a particular NTP association, select the
association and click the Details button. The Details screen is displayed. (See
Figure 2-99.)