Configures the Greenwich Mean Time (GMT) offset and Daylight Saving Time (DST) preference.
|tz_name||Specifies an optional name for this timezone specification. May be up to six alphabetic characters in length. The default is an empty string.|
|GMT_offset||Specifies a Greenwich Mean Time (GMT) offset, in + or - minutes.|
|autodst||Enables automatic Daylight Saving Time.|
|dst-timezone-ID||Specifies an optional name for this DST specification. May be up to six characters in length. The default is an empty string.|
|dst_offset||Specifies an offset from standard time, in minutes. Value is in the range of 1 to 60. Default is 60 minutes.|
Specifies the day, week, and month of the year to begin or end DST each year. Format is: week day month where:
week is specified as [first | second | third | fourth | last] or 1-5. day is specified as [sunday | monday | tuesday | wednesday | thursday | friday | saturday] or 1-7 (where 1 is Sunday). month is specified as [january | february | march | april | may | june | july | august | september | october | november | december] or 1-12.
Default for beginning is second sunday march; default for ending is first sunday november.
Specifies a specific day of a specific year on which to begin or end DST. Format is: month day year where:
month is specified as 1-12. day is specified as 1-31. year is specified as 2003-2035.
The year must be the same for the begin and end dates.
Specifies the time of day to begin or end Daylight Saving Time. May be specified as an hour (0-23) or as hour:minutes. Default is 2:00.
Disables automatic Daylight Saving Time.
Autodst, beginning every second Sunday in March, and ending every first Sunday in November.
Network Time Protocol (NTP) server 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 geographic location.
The GMT_offset is specified in +/- minutes from the GMT time.
Automatic DST changes can be enabled or disabled. The default configuration, where DST begins on the second Sunday in March at 2:00 AM and ends the first Sunday in November at 2:00 AM, applies to most of North America (beginning in 2007), and can be configured with the following syntax: configure timezone GMT_offst autodst.
- Use the every keyword to specify a year-after-year repeating set of dates (for example, the last Sunday in March every year).
- Use the on keyword to specify a non-repeating, specific date for the specified year. If you use this option, you will need to specify the command again every year.
- The begins specification defaults to every second Sunday in March.
- The ends specification defaults to every first sunday november.
- The ends date may occur earlier in the year than the begins date. This will be the case for countries in the Southern Hemisphere.
- If you specify only the starting or ending time (not both) the one you leave unspecified will be reset to its default.
- The time_of_day specification defaults to 2:00.
- The timezone IDs are optional. They are used only in the display of timezone configuration information in the show switch command.
To disable automatic DST changes, re-specify the GMT offset using the noautodst option: configure timezone gmt_offst noautodst.
Greenwich Mean Time offsets
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. configure timezone describes the GMT offsets.
|GMT Offset in Hours||GMT Offset in Minutes||Common Time Zone References||Cities|
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||Cape Verde Islands|
|-2:00||-120||AT - Azores||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|
|-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|
|-9:00||-540||YST - Yukon Standard|
AHST - Alaska-Hawaii Standard
CAT - Central Alaska
HST - Hawaii Standard
|-11:00||-660||NT - Nome|
|-12:00||-720||IDLW - International Date Line West|
CET - Central European
FWT - French Winter
MET - Middle European
MEWT - Middle European Winter
SWT - Swedish Winter
|Paris, France; Berlin, Germany; Amsterdam, The Netherlands; Brussels, Belgium; Vienna, Austria; Madrid, Spain; Rome, Italy; Bern, Switzerland; Stockholm, Sweden; Oslo, Norway|
|+2:00||+120||EET - Eastern European, Russia Zone 1||Athens, Greece; Helsinki, Finland; Istanbul, Turkey; Jerusalem, Israel; Harare, Zimbabwe|
|+3:00||+180||BT - Baghdad, Russia Zone 2||Kuwait; Nairobi, Kenya; Riyadh, Saudi Arabia; Moscow, Russia; Tehran, Iran|
|+4:00||+240||ZP4 - Russia Zone 3||Abu Dhabi, UAE; Muscat; Tblisi; Volgograd; Kabul|
|+5:00||+300||ZP5 - Russia Zone 4|
|+5:30||+330||IST – India Standard Time||New Delhi, Pune, Allahabad, India|
|+6:00||+360||ZP6 - Russia Zone 5|
|+7:00||+420||WAST - West Australian Standard|
|+8:00||+480||CCT - China Coast, Russia Zone 7|
|+9:00||+540||JST - Japan Standard, Russia Zone 8|
EAST - East Australian Standard
GST - Guam Standard
Russia Zone 9
IDLE - International Date Line East
NZST - New Zealand Standard
NZT - New Zealand
|Wellington, New Zealand; Fiji, Marshall Islands|
|+13:00||+780||PHOT-Phoenix Island Time||Kanton Island|
|+14:00||+840||LINT-Line Islands Time||Kiritimati|
For name creation guidelines and a list of reserved names, see Object Names in the Switch Engine 32.2 User Guide .
The following example configures GMT offset for Mexico City, Mexico and disables automatic DST:
# configure timezone -360 noautodst
The following four commands are equivalent, and configure the GMT offset and automatic DST adjustment for the US Eastern timezone, with an optional timezone ID of EST:
3 configure timezone name EST -300 autodst name EDT 60 begins every second sunday march at 2 ends every first sunday november at 2:00 # configure timezone name EST -300 autodst name EDT 60 begins every 1 1 4 at 2:00 ends every 5 1 10 at 2:00 # configure timezone name EST -300 autodst name EDT # configure timezone -300 autodst
The following example configures the GMT offset and automatic DST adjustment for the Middle European timezone, with the optional timezone ID of MET:
# configure timezone name MET 60 autodst name MDT begins every last sunday march at 1 ends every last sunday october at 1
The following command configures the GMT offset and automatic DST adjustment for New Zealand. The ending date must be configured each year because it occurs on the first Sunday on or after March 5:
# configure timezone name NZST 720 autodst name NZDT 60 begins every first sunday october at 2 ends on 3/16/2002 at 2
This command was first available in ExtremeXOS 10.1.
This command is available on ExtremeSwitching 5320, 5420, 5520, and 5720 series switches.