Event Notifications and Amazon SNS - Amazon ElastiCache for Redis

Event Notifications and Amazon SNS

ElastiCache can publish messages using Amazon Simple Notification Service (SNS) when significant events happen on a cache cluster. This feature can be used to refresh the server-lists on client machines connected to individual cache node endpoints of a cache cluster.

Note

For more information on Amazon Simple Notification Service (SNS), including information on pricing and links to the Amazon SNS documentation, see the Amazon SNS product page.

Notifications are published to a specified Amazon SNS topic. The following are requirements for notifications:

  • Only one topic can be configured for ElastiCache notifications.

  • The AWS account that owns the Amazon SNS topic must be the same account that owns the cache cluster on which notifications are enabled.

  • The Amazon SNS topic you are publishing to cannot be encrypted.

Example ElastiCache SNS Notification

ElastiCache Events

The following ElastiCache events trigger Amazon SNS notifications. For information on event details, see Viewing ElastiCache Events.

Event Name Message Description

ElastiCache:AddCacheNodeComplete

ElastiCache:AddCacheNodeComplete : cache-cluster

A cache node has been added to the cache cluster and is ready for use.

ElastiCache:AddCacheNodeFailed due to insufficient free IP addresses

ElastiCache:AddCacheNodeFailed : cluster-name

A cache node could not be added because there are not enough available IP addresses.

ElastiCache:CacheClusterParametersChanged

ElastiCache:CacheClusterParametersChanged : cluster-name

One or more cache cluster parameters have been changed.

ElastiCache:CacheClusterProvisioningComplete

ElastiCache:CacheClusterProvisioningComplete cluster-name-0001-005

The provisioning of a cache cluster is completed, and the cache nodes in the cache cluster are ready to use.

ElastiCache:CacheClusterProvisioningFailed due to incompatible network state

ElastiCache:CacheClusterProvisioningFailed : cluster-name

An attempt was made to launch a new cache cluster into a nonexistent virtual private cloud (VPC).

ElastiCache:CacheClusterScalingComplete

CacheClusterScalingComplete : cluster-name

Scaling for cache-cluster completed successfully.

ElastiCache:CacheClusterScalingFailed

ElastiCache:CacheClusterScalingFailed : cluster-name

Scale-up operation on cache-cluster failed.

ElastiCache:CacheClusterSecurityGroupModified

ElastiCache:CacheClusterSecurityGroupModified : cluster-name

One of the following events has occurred:

  • The list of cache security groups authorized for the cache cluster has been modified.

  • One or more new EC2 security groups have been authorized on any of the cache security groups associated with the cache cluster.

  • One or more EC2 security groups have been revoked from any of the cache security groups associated with the cache cluster.

ElastiCache:CacheNodeReplaceStarted

ElastiCache:CacheNodeReplaceStarted : cluster-name

ElastiCache has detected that the host running a cache node is degraded or unreachable and has started replacing the cache node.

Note

The DNS entry for the replaced cache node is not changed.

In most instances, you do not need to refresh the server-list for your clients when this event occurs. However, some cache client libraries may stop using the cache node even after ElastiCache has replaced the cache node; in this case, the application should refresh the server-list when this event occurs.

ElastiCache:CacheNodeReplaceComplete

ElastiCache:CacheNodeReplaceComplete : cluster-name

ElastiCache has detected that the host running a cache node is degraded or unreachable and has completed replacing the cache node.

Note

The DNS entry for the replaced cache node is not changed.

In most instances, you do not need to refresh the server-list for your clients when this event occurs. However, some cache client libraries may stop using the cache node even after ElastiCache has replaced the cache node; in this case, the application should refresh the server-list when this event occurs.

ElastiCache:CacheNodesRebooted

ElastiCache:CacheNodesRebooted : cluster-name

One or more cache nodes has been rebooted.

Message (Memcached): "Cache node %s shutdown" Then a second message: "Cache node %s restarted"

ElastiCache:CertificateRenewalComplete (Redis only)

ElastiCache:CertificateRenewalComplete

The Amazon CA certificate was successfully renewed.

ElastiCache:CreateReplicationGroupComplete

ElastiCache:CreateReplicationGroupComplete : cluster-name

The replication group was successfully created.

ElastiCache:DeleteCacheClusterComplete

ElastiCache:DeleteCacheClusterComplete : cluster-name

The deletion of a cache cluster and all associated cache nodes has completed.

ElastiCache:FailoverComplete (Redis only)

ElastiCache:FailoverComplete : mycluster

Failover over to a replica node was successful.

ElastiCache:ReplicationGroupIncreaseReplicaCountFinished

ElastiCache:ReplicationGroupIncreaseReplicaCountFinished : cluster-name-0001-005

The number of replicas in the cluster has been increased.

ElastiCache:ReplicationGroupIncreaseReplicaCountStarted

ElastiCache:ReplicationGroupIncreaseReplicaCountStarted : cluster-name-0003-004

The process of adding replicas to your cluster has begun.

ElastiCache:NodeReplacementCanceled

ElastiCache:NodeReplacementCanceled : cluster-name

A node in your cluster that was scheduled for replacement is no longer scheduled for replacement.

ElastiCache:NodeReplacementRescheduled

ElastiCache:NodeReplacementRescheduled : cluster-name

A node in your cluster previously scheduled for replacement has been rescheduled for replacement during the new window described in the notification.

For information on what actions you can take, see Replacing Nodes.

ElastiCache:NodeReplacementScheduled

ElastiCache:NodeReplacementScheduled : cluster-name

A node in your cluster is scheduled for replacement during the window described in the notification.

For information on what actions you can take, see Replacing Nodes.

ElastiCache:RemoveCacheNodeComplete

ElastiCache:RemoveCacheNodeComplete : cluster-name

A cache node has been removed from the cache cluster.

ElastiCache:ReplicationGroupScalingComplete

ElastiCache:ReplicationGroupScalingComplete : cluster-name

Scale-up operation on replication group completed successfully.

ElastiCache:ReplicationGroupScalingFailed

"Failed applying modification to cache node type to %s."

Scale-up operation on replication group failed.

ElastiCache:SnapshotComplete (Redis only)

ElastiCache:SnapshotComplete : cluster-name

A cache snapshot has completed successfully.

ElastiCache:SnapshotFailed (Redis only)

SnapshotFailed : cluster-name

A cache snapshot has failed. See the cluster’s cache events for more a detailed cause.

If you describe the snapshot, see DescribeSnapshots, the status will be failed.

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