clock summer-time
Sets the device clock summer-time and time zone options.
Syntax
Command Default
The default start and end time of day light savings will depend on the longitude of the country. See the Usage Guidelines section for details.
Parameters
- australia australia-time
- Specifies the Australia time zone. The value can be one of the following: cst (UTC+9.5), est (UTC+10), wst (UTC+8).
- europe europe-time
- Specifies the Europe time zone. The value can be one of the following: gmt (UTC), bst (UTC+1), ist (UTC+8), wet (UTC), west (UTC+1), cet (UTC+!), cest (UTC+2), eet (UTC+2), eest (UTC+3), msk (UTC+3), msd (UTC+4).
- gmt gmt-time
- Specifies the GMT time zone. The value can be one of the following: gmt+00 (United Kingdom), gmt+01 (France, Germany), gmt+02 (Eastern Europe, South Africa), gmt+03, gmt+03:30, gmt+04, gmt+04:30, gmt+05, gmt+05:30 (India), gmt+06, gmt+06:30, gmt+07, gmt+08 (China, Hong Kong, Taiwan), gmt+09 (Japan, Korea), gmt+09:30, gmt+10 (Australia), gmt+10:30, gmt+11, gmt+11:30, gmt+12, gmt-01, gmt-02, gmt-03, gmt-03:30, gmt-04, gmt-05, gmt-06, gmt-07, gmt-08, gmt-08:30, gmt-09, gmt-09:30, gmt-10, gmt-11, gmt-12.
- us us-time
- Specifies the US time zone. The value can be one of the following: alaska, aleutian, arizona, central, east-indiana, eastern, hawaii, michigan, mountain, pacific, samoa.
- start mm-dd-yy hh:mm:ss
- Specifies the summer-time start date and time for the local clock time in month, day, and year and hours, minutes, and seconds.
- end mm-dd-yy hh:mm:ss
- Specifies the summer-time end date and time for the local clock time in month, day, and year and hours, minutes, and seconds.
- offset offset-value
- Specifies the summer-time offset, in minutes.
Modes
Global configuration mode
Usage Guidelines
The clock summer-time command without any parameters sets the default daylight savings time for the corresponding time zone. Use this command with specific parameters if you need to manually configure the local clock summer-time and time zones values. Use the clock timezone command to set the device clock time zone with a default daylight savings time.
By default, daylight savings are implemented according to time zone in three sets of dates and times:
- USA—Summer time starts at 2:00am on the second Sunday of March and ends at 2:00am on the first Sunday of November.
- Europe—Summer time starts at 2:00am on the last Sunday of March and ends at 2:00am on the last Sunday of October.
- Rest of the world—Summer time starts at 2:00am on the last Sunday of March and ends at 2:00am on the last Sunday of October, but some countries have different start and end dates depending on the longitude.
When the configured time zone is different from the existing time zone due to a configuration of the time zone using the clock summer-time command, a y/n option appears.
The no form of this command disables daylight savings.
Examples
The following example sets the local device clock that resides in the US Central time zone to the US Mountain standard time zone, and you are reminded of this change with a y/n prompt. The daylight savings times are also different than the default for any US time zone.
device# configure terminal Router(config)# clock summer-time zone us mountain start 10-30-16 02:00:00 end 02-27-17 02:00:00 offset 30 You are about to change the timezone config do you want to continue yes or no (enter 'y' or 'n'): y
The following example removes the daylight savings set for the local device clock.
device# configure terminal device(config)# no clock summer-time
History
| Release version | Command history |
|---|---|
| 8.0.50 | This command was modified to add subsets of time zones specific to Australia and Europe. |