Concept Guide

NOTE:
• Leap Indicator (sys.leap, peer.leap, pkt.leap) — This is a two-bit code warning of an impending leap second to be
inserted in the NTP time scale. The bits are set before 23:59 on the day of insertion and reset after 00:00 on the following day. This
causes the number of seconds (rollover interval) in the day of insertion to be increased or decreased by one. In the case of primary
servers, the bits are set by operator intervention, while in the case of secondary servers, the bits are set by the protocol. The two
bits, bit 0, and bit 1, respectively, are coded as follows:
• Poll Interval — integer indicating the minimum interval between transmitted messages, in seconds as a power of two. For
instance, a value of six indicates a minimum interval of 64 seconds.
• Precision — integer indicating the precision of the various clocks, in seconds to the nearest power of two. The value must be
rounded to the next larger power of two; for instance, a 50 Hz (20 ms) or 60 Hz (16.67ms) power-frequency clock is assigned the
value -5 (31.25 ms), while a 1000 Hz (1 ms) crystal-controlled clock is assigned the value -9 (1.95 ms).
• Root Delay (sys.rootdelay, peer.rootdelay, pkt.rootdelay) — a signed xed-point number indicating the total
round-trip delay to the primary reference source at the root of the synchronization subnet, in seconds. This variable can take on
both positive and negative values, depending on clock precision and skew.
• Root Dispersion (sys.rootdispersion, peer.rootdispersion, pkt.rootdispersion) — a signed xed-point
number indicating the maximum error relative to the primary reference source at the root of the synchronization subnet, in
seconds. Only positive values greater than zero are possible.
• Reference Clock Identier (sys.refid, peer.refid, pkt.refid) — This is a 32-bit code identifying the particular
reference clock. In the case of stratum 0 (unspecied) or stratum 1 (primary reference source), this is a four-octet, left-justied,
zero-padded ASCII string, for example: in the case of stratum 2 and greater (secondary reference) this is the four-octet internet
address of the peer selected for synchronization.
• Reference Timestamp (sys.reftime, peer.reftime, pkt.reftime) — This is the local time, in timestamp format, when
the local clock was last updated. If the local clock has never been synchronized, the value is zero.
• Originate Timestamp: The departure time on the server of its last NTP message. If the server becomes unreachable, the value is
set to zero.
• Receive Timestamp — the arrival time on the client of the last NTP message from the server. If the server becomes unreachable,
the value is set to zero.
• Transmit Timestamp — the departure time on the server of the current NTP message from the sender.
• Filter dispersion — the error in calculating the minimum delay from a set of sample data from a peer.
Conguring NTP control key password
The Network Time Protocal daemon (NTPD) design uses NTPQ to congure NTPD. NTP control key supports encrypted and unencrypted
password options. The ntp control-key- passwd command authenticates NTPQ packets. The default control-key-passwd
authenticates the NTPQ packets until the user changes the control-key using the ntp control-key- passwd command.
To congure NTP control key password, use the following command.
Congure NTP control key password.
CONFIGURATION mode
ntp control-key-passwd [encryption-type] password
Dell Networking OS Time and Date
You can set the time and date using the Dell Networking OS CLI.
Conguration Task List
The following is a conguration task list for conguring the time and date settings.
• Setting the Time and Date for the Switch Software Clock
• Setting the Timezone
System Time and Date
865