Time Management
Time Management
1. Function Overview
This product provides the functions shown below for managing the date and time.
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Manual (user-configured) date/time information setting function
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Automatic date/time setting information function via network
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Time zone setting function
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Function for setting “daylight saving time” (DST or “daylight time”) settings
2. Definition of Terms Used
UTC(Coordinated Universal Time)
This is an official time used when recording worldwide times.
UTC is used as a basis to determine standard time in all countries around the world.
For instance, Japan (JST, or Japan standard time) is nine hours ahead of Coordinated Universal Time, and is thus shown as “+0900 (JST)”.
SNTP(Simple Network Time Protocol)
This is a simple protocol to correct clocks by using SNTP packets.
This protocol is defined in RFC4330.
3. Function Details
3.1. Manually setting the date and time
Use the clock set command to directly enter clock setting values.
3.2. Automatically setting the date and time
Date and time information is collected from a specified time server, and set in this product.
Defined in RFC4330, SNTP (Simple Network Time Protocol) is used as a communication protocol.
Up to two time servers can be specified using an IPv4 address, IPv6 address, or fully qualified domain name (FQDN).
Port number 123 is used for the SNTP client. (This setting cannot be changed by the user.)
The ntpdate command can be used to select one of two methods for automatically setting date and time settings.
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One-shot update (a function to update when a command is inputted)
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Interval update (a function to update in a 1–24-hour cycle from command input)
If clock settings are synchronized with two time servers specified, queries are processed in the order they are displayed by the show ntpdate command, which is NTP server 1 and then NTP server 2.
Queries to NTP server 2 are only processed if synchronization with NTP server 1 fails.
Given default settings, one hour is specified as the interval update cycle.
However, when the default time cannot be set right after booting up the system, the time server will be queried in a one-minute cycle, regardless of the interval cycle time.
Synchronization with the time server operates with one sampling (the frequency of replies from the server) and with a timeout of 1 second.
Synchronization is blocked during command execution, and an error message is outputted if a timeout occurs.
3.3. Time zone setting
In order to manage the time for the region considered as the “base of daily life”, the “clock timezone” command is used to manage the time zone of the users, and reflect this into the time.
The time zone can be set in ±1 hour increments for Coordinated Universal Time (UTC), from -12 hours to +13 hours.
The default time zone value for this product is +9.0.
3.4. Daylight saving time setting
Users can set “daylight saving time” (DST or “daylight time”) settings using the clock summer-time command.
The following parameter settings are specified.
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Time zone name
The time zone name is displayed when daylight saving time is in effect. -
Start and end times of daylight saving time
You can specify the time in one of two ways:-
Recurring
If daylight saving time occurs every year for the same period, then this specifies the week and day of the month it occurs. -
Specific dates
This specifies the specific dates daylight saving time is applied.
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Offset
This specifies how long (minutes) to extend the daylight saving time period.
The setting range is from 1 to 1440 minutes. The setting value is 60 minutes unless specified otherwise.
Overlapping daylight saving time periods cannot be specified.
Daylight saving time settings can be checked using the show clock detail command.
4. Related Commands
Related commands are indicated below.
For details, refer to the Command Reference.
Operations | Operating commands |
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Set clock manually |
clock set |
Time zone setting |
clock timezone |
Set daylight saving time settings (recurring) |
clock summer-time recurring |
Set daylight saving time settings (specific date) |
clock summer-time date |
Show current time |
show clock |
Set NTP server |
ntpdate server |
Synchronize time from NTP server (one-shot update) |
ntpdate oneshot |
Synchronize time from NTP server (update interval) |
ntpdate interval |
Show NTP server time synchronization settings |
show ntpdate |
5. Examples of Command Execution
5.1. Set clock manually
In this example, the time zone is set to JST and the current time is set to 2014.01.21 15:50:59.
Yamaha#configure terminal Yamaha(config)#clock timezone JST (1) Yamaha(config)#exit Yamaha#clock set 15:50:59 Jan 21 2014 (2) Yamaha#show clock (3) 15:50:59 JST Tue Jan 21 2014
1 | Time zone setting |
2 | Time settings |
3 | Show current time |
5.2. Automatically setting the time
In this example, the time zone is set to +9.00 and the local address 192.168.1.1 and ntp.nict.jp are specified as the NTP servers.
Also, the NTP server update cycle is changed to once every 24 hours.
Yamaha#configure terminal Yamaha(config)#clock timezone +9:00 (1) Yamaha(config)#ntpdate server ipv4 192.168.1.1 (2) Yamaha(config)#ntpdate server name ntp.nict.jp (3) Yamaha(config)#ntpdate interval 24 (4) Yamaha(config)#exit Yamaha#show clock (5) 10:03:20 +9:00 Mon Dec 12 2016 Yamaha#show ntpdate (6) NTP server 1 : 192.168.100.1 NTP server 2 : ntp.nict.jp adjust time : Mon Dec 12 10:03:15 2016 + interval 24 hours sync server : 192.168.100.1
1 | Time zone setting |
2 | Set NTP server |
3 | Set NTP server |
4 | Set NTP server update cycle to 24 hours |
5 | Show current time |
6 | Show NTP time synchronization settings |
5.3. Daylight saving time setting
5.3.1. Recurring
In this example, daylight saving time is set to occur every year starting from 2 AM on the second Sunday of March to 2 AM on the first Sunday of November.
Yamaha#configure terminal Yamaha(config)#clock summer-time JDT recurring 2 Sun Mar 2:00 1 Sun Nov 2:00 (1) Yamaha(config)#exit Yamaha#show clock detail (2) Fri Jan 1 00:00:20 JST 2021 Summer Time Type : Recurring Offset : 60 (min) From : Sun Mar 14 02:00:00 JST 2021 (3) To : Sun Nov 7 02:00:00 JDT 2021
1 | Daylight saving time setting |
2 | Check the daylight saving time settings |
3 | Show the actual dates of the next (or currently in effect) daylight saving time period |
5.3.2. Specific dates
In this example, the settings specify starting daylight saving time at 2 AM on March 14, 2021, and ending it on November 7, 2021.
Yamaha#configure terminal Yamaha(config)#clock summer-time JDT date Mar 14 2021 2:00 Nov 7 2021 2:00 (1) Yamaha(config)#exit Yamaha#show clock detail (2) Fri Jan 1 00:02:54 JST 2021 Summer Time Type : Date Offset : 60 (min) From : Sun Mar 14 02:00:00 JST 2021 To : Sun Nov 7 02:00:00 JDT 2021
1 | Daylight saving time setting |
2 | Check the daylight saving time settings |
6. Points of Caution
None