Amazon ElastiCache
User Guide (API Version 2012-11-15)
« PreviousNext »
View the PDF for this guide.Go to the AWS Discussion Forum for this product.Go to the Kindle Store to download this guide in Kindle format.Did this page help you?  Yes | No |  Tell us about it...

Cache Engine Version Management

You can control if and when the Memcached protocol-compliant software powering your cache cluster is upgraded to new versions that are supported by ElastiCache. This enables you to maintain compatibility with specific Memcached versions, test new versions with your application before deploying in production, and perform version upgrades on your own terms and timelines.

Since major version upgrades involve some compatibility risk, they will not occur automatically and must be initiated by you. Automatic patching works only for minor upgrades; for example, from version 1.4.5 to 1.4.6. Automatic patching will not work for major upgrades (for example, from version 1.4.x to 1.5.x). You can manually initiate major version upgrades to your cache cluster by modifying the cache cluster and specifying a new engine version.

Note

While Cache Engine Version Management functionality is intended to give you as much control as possible over how patching occurs, ElastiCache reserves the right to patch your cache cluster on your behalf in the event of a critical security vulnerability in the system or cache software.

Automatic patching will occur during the scheduled maintenance window for your cache clusters, and will be announced on the ElastiCache discussion forum in advance. Automatic version upgrades are enabled by default on new cache clusters; if you wish to turn off automatic version upgrades, you can do so by selecting the “Auto Minor Version Upgrade” for your cache cluster to “No”.