Administrator Guide

Configure the Network Time Protocol
Configuring NTP is a one-step process.
• Enabling NTP
Related Configuration Tasks
• Configuring NTP Broadcasts
• Setting the Hardware Clock with the Time Derived from NTP
• Disabling NTP on an Interface
• Configuring a Source IP Address for NTP Packets (optional)
Enabling NTP
NTP is disabled by default.
To enable NTP, specify an NTP server to which the Dell Networking system synchronizes. To specify
multiple servers, enter the command multiple times. You may specify an unlimited number of servers at
the expense of CPU resources.
• Specify the NTP server to which the Dell Networking system synchronizes.
CONFIGURATION mode
ntp server ip-address
Examples of Viewing System Clock
To display the system clock state with respect to NTP, use the show ntp status command from EXEC
Privilege mode.
R6_E300(conf)#do show ntp status
Clock is synchronized, stratum 2, reference is 192.168.1.1
frequency is -369.623 ppm, stability is 53.319 ppm, precision is 4294967279
reference time is CD63BCC2.0CBBD000 (16:54:26.049 UTC Thu Mar 12 2009)
clock offset is 997.529984 msec, root delay is 0.00098 sec
root dispersion is 10.04271 sec, peer dispersion is 10032.715 msec
peer mode is client
To display the calculated NTP synchronization variables received from the server that the system uses to
synchronize its clock, use the show ntp associations command from EXEC Privilege mode.
R6_E300(conf)#do show ntp associations
remote ref clock st when poll reach delay offset disp
==========================================================
#192.168.1.1 .LOCL. 1 16 16 76 0.98 -2.470 879.23
* master (synced), # master (unsynced), + selected, - candidate
Setting the Hardware Clock with the Time Derived from NTP
To set the hardware clock, use the following command.
• Periodically update the system hardware clock with the time value derived from NTP.
CONFIGURATION mode
ntp update-calendar
System Time and Date
805