View definition

(ModifyCacheClusterInput).NumCacheNodes

Defined in github.com/aws/aws-sdk-go/service/elasticache/api.go

Description

The number of cache nodes that the cache cluster should have. If the value for NumCacheNodes is greater than the sum of the number of current cache nodes and the number of cache nodes pending creation (which may be zero), then more nodes will be added. If the value is less than the number of existing cache nodes, then nodes will be removed. If the value is equal to the number of current cache nodes, then any pending add or remove requests are canceled.

If you are removing cache nodes, you must use the CacheNodeIdsToRemove parameter to provide the IDs of the specific cache nodes to remove.

For clusters running Redis, this value must be 1. For clusters running Memcached, this value must be between 1 and 20.

Adding or removing Memcached cache nodes can be applied immediately or

as a pending action. See ApplyImmediately.

A pending action to modify the number of cache nodes in a cluster during its maintenance window, whether by adding or removing nodes in accordance with the scale out architecture, is not queued. The customer's latest request to add or remove nodes to the cluster overrides any previous pending actions to modify the number of cache nodes in the cluster. For example, a request to remove 2 nodes would override a previous pending action to remove 3 nodes. Similarly, a request to add 2 nodes would override a previous pending action to remove 3 nodes and vice versa. As Memcached cache nodes may now be provisioned in different Availability Zones with flexible cache node placement, a request to add nodes does not automatically override a previous pending action to add nodes. The customer can modify the previous pending action to add more nodes or explicitly cancel the pending request and retry the new request. To cancel pending actions to modify the number of cache nodes in a cluster, use the ModifyCacheCluster request and set NumCacheNodes equal to the number of cache nodes currently in the cache cluster.