The time zones feature of Redwood Server makes it easy to manage scheduler environments that span multiple time zones. For example, assume there is an office in London. High-load processes need to be scheduled to run on the server in New York. These processes run in the night in New York so that the extra server load does not affect the people in the New York office. The process can be submitted to start at 01:00 (for example 1 AM) in the New York time zone and the time offset of London to New York does not need to be calculated. Daylight saving times can be hard to remember, especially when you have to manage multiple time zones on different parts of the globe. Redwood Server now displays Daylight saving time alongside the offset to help you understand the current offset.

The time zone of a process is the one you specified in the submit wizard. When the process was submitted without a specific time zone, from RedwoodScript for example, the central Redwood Server time zone is used for the time zone.

note

The central Redwood Server uses the time zone information from the JVM. This data needs to be kept up-to-date for all time zones you use. This is especially true for Daylight Saving Times, which have been changed in various countries in the last years.

Olson Time Zones

Redwood Server uses the Olson time zone format. All time and date calculations are done in the context of a time zone. In most cases this time zone is either simply the session time zone or an explicitly provided time zone.

Arthur Olson started the "America/New York" style time zone definitions that were first put into BSD 4.3. Most if not all Unices now support this style. The official term for them is the "tz" database. The time zones are publicly stored at ftp.iana.org/tz/ and regularly updated. The Olson time zone definitions are a standard reference on what times were historically, for the last hundred years.

Time zones are part of the Environment section in the navigation bar. The time zones available are loaded directly from the Java Time Zone database when Redwood Server is installed.

Daylight Saving Time (DST)

Many countries have implemented Daylight Savings Time (DST). Under DST the sun rises an hour earlier, and sets an hour earlier, according to the clock. During the changeover from normal time to DST, the clock is moved forward an hour, and when leaving DST the clock is moved back an hour. For computer systems this means an hour of the day occurs twice or is skipped. Redwood Server has no issues with time switches. If systems in your data-center run Redwood Server processes and need to be shut-down over the switch period (usually SAP systems), ensure you have held all of the affected queues before shutting down the SAP systems, as you do not want new processes to start. Please wait until all processes have reached a final state before shutting SAP systems down. Avoid releasing all queues simultaneously, or the SAP systems might get overloaded as soon as they become available. You can also use time windows to achieve the above without human intervention at the time of the date-change.

Etc/GMT Offsets

The etcetera timezone definitions were added to the Olson timezone database to cater for POSIX notation. These timezone definitions do not take DST changes into account. The offset specifies the time value you must add to the local time to get a Coordinated Universal Time value; so Paris, France, would be Etc/GMT-1 which is reversed from what you would expect. There is no equivalent for the GMT+1 notation in the Olson timezone database.

When Redwood Server encounters a time expression with an offset instead of an Olson timezone name, the date will be displayed using the POSIX notation because it is the only notation available that supports offsets. Note that there are multiple Olson timezone names for any given offset.

Deprecated Time Zones

The following time zones have been deprecated in Java and should not longer be used:

ACT, AET, AGT, ART, AST, BET, BST, CAT, CNT, CST, CTT, EAT, ECT, EST, HST, IET, IST, JST, MIT, MST, NET, NST, PLT, PNT, PRT, PST, SST, and VST.

If you use any of these, you should change it to a supported time zone for your region, navigate to Environment > Time Zones and select an appropriate time zone with the name <continent>/<city>.

Context-Menu

Time zones support the following context-menu actions:

Action	Description
Edit	Edit the time zone
Hide in timezone lists	Hide the current time zone in timezone lists
Show in timezone lists	Show the current time zone in timezone lists
Show permalinks	Show links that can be used from third party applications to link to the object
Add to navigation bar	Add the current object to the navigation bar
Filter > New Filter	Create a new time zone filter
Filter > Edit Filter	Edit current time zone filter
Filter > Delete	Delete current time zone filter
Filter > Duplicate Filter	Create a copy of the filter
Filter > Export Filter	Export the filter into a CAR file
Filter > Add to navigation bar	Add the filter to a navigation bar
Filter > Create filter from search	Create a filter from the current IntelliSearch query

It is only possible to edit the description of a time zone (which is used in preference to the name for display purposes). It is not possible to edit any of the other attributes.

Finding Time Zones

You can search for time zones using filters and the Search Time Zones box on the Time Zones tab. This box is known as the IntelliSearch box and located under your username on the top right-hand side of the user interface. Filters allow you to specify a list of objects with static criteria. IntelliSearch allows you to specify complex queries in a simple way using prefixes. Prefixes are used to specify which property you are searching in and have short as well as long syntaxes. For example, if you want to display all time zones with the term import in the comment, you would use the search criteria as follows:

c:import

You can search more than one property, as follows:

c:import n:Bi

note

No spaces should be entered before or after the colon (: ).

See the Advanced Object Search for more information.

The following table illustrates the available prefixes for time zones:

Prefixes	Description
n, name	searches the name property
c, com, comment	searches the documentation property
d, desc, description	searches the description property

Procedure

Choose "Environment > Time Zones" and choose a time zone.
From the context-menu, choose Edit.
Enter a description and comment.
Choose Save and Close to save the time zone.

Time Zone Tab

Name - The name of the time zone.
Description - The description of the time zone.

Documentation Tab

Documentation - A comment about the time zone.

Example

Choose "Environment > Time Zones" and select the Europe/Berlin time zone.
From the context-menu, choose Edit.
Enter Europe/Walldorf as description.
Choose Save and Close to save the time zone.

time zone timezone DST Olson Offsets clock date