# Service updates in MemoryDB
<a name="service-updates"></a>

MemoryDB automatically monitors your fleet of clusters and nodes to apply service updates as they become available. Typically, you set up a predefined maintenance window so that MemoryDB can apply these updates. However, in some cases you might find this approach too rigid and likely to constrain your business flows. 

With [Service updates in MemoryDB](#service-updates), you control when and which updates are applied. You can also monitor the progress of these updates to your selected MemoryDB cluster in real time. 

## Applying the service updates using the AWS CLI
<a name="applying-updates-cli-redis"></a>

After you receive notification that service updates are available, you can inspect and apply them using the AWS CLI:
+ To retrieve a description of the service updates that are available, run the following command:

  `aws memorydb describe-service-updates --status available`

  For more information, see [describe-service-updates](https://docs.aws.amazon.com/cli/latest/reference/memorydb/describe-service-updates.html). 
+ To apply a service update on a list of clusters, run the following command:

  `aws memorydb batch-update-cluster --service-update ServiceUpdateNameToApply=sample-service-update --cluster-names cluster-1 cluster2`

  For more information, see [batch-update-cluster](https://docs.aws.amazon.com/cli/latest/reference/memorydb/batch-update-cluster.html).