DistributedDirector Cache Auto Refresh
Note
Effective with Cisco IOS Release 12.4(24)T, this feature is not available in Cisco IOS software.
Feature History
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12.2(8)T |
This feature was introduced. |
12.4(24)T |
This feature was removed. |
This document describes the DistributedDirector Cache Auto Refresh feature in Cisco IOS Release 12.2(8)T. It includes the following sections:
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Feature Overview
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Finding Feature Information
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Supported Standards, MIBs, and RFCs
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Prerequisites
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Configuration Tasks
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Configuration Examples
Feature Overview
The DistributedDirector Cache Auto Refresh feature works in the background to continuously update all entries in the DistributedDirector cache. Once this background refresh feature is initiated, DistributedDirector periodically updates all expired cache entries. The DistributedDirector cache saves the latest answers to all past Domain Name System (DNS) queries received since cache auto refresh was initiated, and any repeat request is served directly from the cache when caching is enabled.
The new ip director cache refresh command enables the automatic background refresh feature for the DistributedDirector cache.
Benefits
Once the cache auto refresh feature is enabled, the cache will actively and continuously update every expired entry. This feature allows DistributedDirector to return answers to queries according to the latest and most accurate network information.
Related Technologies
DistributedDirector Configurable Cache
Related Documents
DistributedDirector Configurable Cache, Cisco IOS Release 12.2(8)T feature module
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Supported Standards, MIBs, and RFCs
Standards
No new standards are supported by this feature.
MIBs
No new MIBs are supported by this feature.
To obtain lists of supported MIBs by platform and Cisco IOS release, and to download MIB modules, go to the Cisco MIB website on Cisco.com at the following URL:
http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml
RFCs
No new RFCs are supported by this feature.
Prerequisites
The sorting cache must be enabled on DistributedDirector. To enable the sorting cache, use the ip director cache command.
Configuration Tasks
See the following section for configuration tasks for cache auto refresh. Each task in the list is identified as either required or optional.
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Enabling Cache Auto Refresh (required)
Enabling Cache Auto Refresh
To enable cache auto refresh for DistributedDirector, use the ip director cache refresh command.
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Step 1 |
Router(config)# ip director cache |
Enables the sorting cache on DistributedDirector. |
Step 2 |
Router(config)# ip director cache refresh |
Enables the DistributedDirector Cache Auto Refresh feature. |
To turn off cache auto refresh, use the no ip director cache refresh command.
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Step 1 |
Router(config)# no ip director cache refresh |
Disables the DistributedDirector Cache Auto Refresh feature. |
Verifying the Cache Auto Refresh Feature
To verify that the DistributedDirector Cache Auto Refresh feature is configured, enter the show running-config command.
Router(config)# ip director cache
Router(config)# ip director cache refresh
Router# show running-config
ip host myhost 172.22.2.10 172.22.2.20 172.22.2.30
ip director cache refresh
Configuration Examples
This section provides the following configuration example:
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Enabling the Cache Auto Refresh Feature Example
Enabling the Cache Auto Refresh Feature Example
In the following example, the cache auto refresh background feature for DistributedDirector is enabled:
Router(config)# ip director cache
Router(config)# ip director cache refresh
Router# show running-config
ip host myhost 172.22.2.10 172.22.2.20 172.22.2.30
ip director cache refresh
Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.
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