Cisco AON Software

Table Of Contents

Impact of U.S. Daylight Saving Time Changes on Cisco Application-Oriented Networking

Overview of Impact and Remedies

Impact of Daylight Saving Time on AON Nodes

Mitigating the Impact of Daylight Saving Time

AON Release 2.4 and Indiana Time Zones

Related Documentation

Obtaining Documentation, Obtaining Support, and Security Guidelines

Impact of U.S. Daylight Saving Time Changes on Cisco Application-Oriented Networking

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March 15, 2007

Most Cisco AON software releases do not include appropriate settings for areas that comply with the Daylight Saving Time (DST) changes specified by the U.S. Energy Policy Act of 2005.

AON Management Console and AON Development Studio are not affected by this issue. These applications derive the time from their host operating systems. Users should be sure to install the appropriate patches from Red Hat and Microsoft.

AON nodes, however, will adjust the time based on the pre-2007 settings, meaning that timestamps and other time-based information are incorrect after March 11, 2007.

Cisco AON Release 2.4 corrects this issue, and all customers are strongly encouraged to upgrade their AON environments. In the mean time, this document describes the impact you can expect following the switch to DST and the actions you should take to mitigate this issue.

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Note This document will be updated and republished as additional information becomes available.

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This document includes the following sections:

•Overview of Impact and Remedies

•Impact of Daylight Saving Time on AON Nodes

•Mitigating the Impact of Daylight Saving Time

•AON Release 2.4 and Indiana Time Zones

•Related Documentation

•Obtaining Documentation, Obtaining Support, and Security Guidelines

Overview of Impact and Remedies

Table 1 lists the impacts expected and the appropriate remedy for each device in an AON environment.

Table 1 Daylight Saving Time Impacts and Remedies

Device	Impact	Remedy
AMC	None. AMC derives the time from the host operating system.	Obtain appropriate patch from Red Hat: http://kbase.redhat.com/faq/FAQ_85_9951
ADS	None. ADS derives the time from the host operating system.	Obtain appropriate patch from Microsoft: http://support.microsoft.com/gp/cp_dst
AON nodes	Timestamps may be off by 1 to 2 hours depending on your locale.	See the "Mitigating the Impact of Daylight Saving Time" section.

Impact of Daylight Saving Time on AON Nodes

The AON software that runs on individual nodes includes its own time zone settings. Because of this, users of nodes located in an area that began Daylight Saving Time on March 11, 2007, can expect the time change to impact the following areas:

•syslog—messages.log, messages.log.prev, and console log messages.

•fastpath—aon-fastpath.log and any code that uses fastpath APIs.

•developer kit.

•cache server—CacheMgr*.log.

•trace debug diagnostics—output from the show trace command and atrace.log.

•Any native software program that relies on the AON operating system date and time zone data.

Furthermore, should you manually correct the time on your AON node after March 11, the node will incorrectly adjust the time on April 1, 2007, the date specified for DST prior to the Energy Policy Act of 2005.

Mitigating the Impact of Daylight Saving Time

The best course of action to mitigate the effects of Daylight Saving Time is to upgrade to Cisco AON Release 2.4. Until you upgrade, you can take the following actions to prevent and correct erroneous time on your pre-2.4 AON node:

•Change the time zone used by the node to Greenwich Mean Time (GMT), which is not affected by DST changes.

•Configure the node to obtain time from a network time protocol (NTP) server that has been patched with correct 2007 DST settings.

To configure your node, perform the following steps:

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Step 1 Establish a session to the node and enter configuration terminal mode

aon-nm> configure terminal

Enter configuration commands, one per line.  End with exit.

Step 2 Configure the node to use GMT

aon-nm(config)> clock timezone GMT

Step 3 Specify a network time protocol (NTP) server that the node can use to maintain accurate time.

aon-nm (config)# ntp server 10.1.1.10

Step 4 Exit configuration terminal mode and save your configuration.

aon-nm(config)> exit

aon-nm> write memory

Step 5 Reload the node.

aon-nm> reload

Are you sure you want to reload?

Doing a reload will cause any unsaved configuration data to be lost.

Continue[y/n]? : y

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AON Release 2.4 and Indiana Time Zones

Cisco AON Release 2.4 includes incorrect time zone information for some areas of the U.S. state of Indiana. To ensure that AON nodes keep the correct time, you must adjust the time zone to one that will generate the correct time for your locale. Table 2 lists time zones for Indiana, along with the configuration terminal command to make the appropriate adjustment.

Table 2 Indiana Time Zone Corrections

Indiana Time Zone	Command to Correct the Time
America/Indiana/Indianapolis	clock timezone EST5EDT
America/Indiana/Marengo	clock timezone EST5EDT
America/Indiana/Vevay	clock timezone EST5EDT
America/Indiana/Knox	clock timezone CST6CDT
America/Indiana/Petersburg	clock timezone CST6CDT
America/Indiana/Vincennes	clock timezone CST6CDT
America/Indiana/Winamac	clock timezone EST5EDT

Related Documentation

The AON documentation set includes the following guides:

•AON Installation and Upgrade Guide—Covers the installation and upgrade of the AON environment.

•AON Administration Guide—Covers the administration of AMC and AON nodes.

•AON Development Studio User Guide—Covers ADS, bladelets, and PEP creation.

•AON Programming Guide—Covers the development of custom bladelets, custom adapters, and other features related to extending AON functionality.

Obtaining Documentation, Obtaining Support, and Security Guidelines

For information on obtaining documentation, obtaining support, providing documentation feedback, security guidelines, and also recommended aliases and general Cisco documents, see the monthly What's New in Cisco Product Documentation, which also lists all new and revised Cisco technical documentation, at:

http://www.cisco.com/en/US/docs/general/whatsnew/whatsnew.html

© 2007 Cisco Systems, Inc. All rights reserved.