Extreme Networks Summit 300-48 - Manual (Page 52)

52 Summit 300-48 Switch Software User Guide
Managing the Switch
Once enabled, the switch sends out a periodic query to the NTP servers defined later (if configured)
or listens to broadcast NTP updates from the network. The network time information is
automatically saved into the on-board real-time clock.
4 If you would like this switch to use a directed query to the NTP server, configure the switch to use
the NTP server(s). If the switch listens to NTP broadcasts, skip this step. To configure the switch to
use a directed query, use the following command:
config sntp-client [primary | secondary] server [<ip_address> | <hostname>]
NTP queries are first sent to the primary server. If the primary server does not respond within 1
second, or if it is not synchronized, the switch queries the secondary server (if one is configured). If
the switch cannot obtain the time, it restarts the query process. Otherwise, the switch waits for the
sntp-client update interval before querying again.
5 Optionally, the interval for which the SNTP client updates the real-time clock of the switch can be
changed using the following command:
config sntp-client update-interval <seconds>
The default sntp-client update-interval value is 64 seconds.
6 You can verify the configuration using the following commands:
— show sntp-client
This command provides configuration and statistics associated with SNTP and its connectivity to
the NTP server.
— show switch
This command indicates the GMT offset, Daylight Savings Time, and the current local time.
NTP updates are distributed using GMT time. To properly display the local time in logs and other
timestamp information, the switch should be configured with the appropriate offset to GMT based on
geographical location. Table 13 describes GMT offsets.
Table 13: Greenwich Mean Time Offsets
GMT
Offset in
Hours
GMT Offset
in Minutes Common Time Zone
References
Cities
+0:00 +0 GMT - Greenwich Mean
UT or UTC - Universal
(Coordinated)
WET - Western European
London, England; Dublin, Ireland;
Edinburgh, Scotland; Lisbon,
Portugal; Reykjavik, Iceland;
Casablanca, Morocco
-1:00 -60 WAT - West Africa Azores, Cape Verde Islands
-2:00 -120 AT - Azores
-3:00 -180 Brasilia, Brazil; Buenos Aires,
Argentina; Georgetown, Guyana;
-4:00 -240 AST - Atlantic Standard Caracas; La Paz
-5:00 -300 EST - Eastern Standard Bogota, Columbia; Lima, Peru;
New York, NY, Trevor City, MI
USA
-6:00 -360 CST - Central Standard Mexico City, Mexico
-7:00 -420 MST - Mountain Standard Saskatchewan, Canada
-8:00 -480 PST - Pacific Standard Los Angeles, CA, Cupertino, CA,
Seattle, WA USA