Question: Is Memcached Multi-AZ?

Answer

No, Memcached does not natively support multi-AZ (availability zone) deployment. It is designed as an in-memory caching solution that stores data in memory and provides fast access to frequently used data to speed up web applications.

Multi-AZ deployment refers to deploying the same application or service in multiple availability zones in a given region. This approach ensures high availability and fault tolerance by distributing the workload across different zones. In case of a failure in one zone, the traffic can be routed to another zone without disruption.

However, there are ways to achieve multi-AZ deployment with Memcached using third-party tools like ElastiCache for Memcached, which is a managed caching service provided by AWS. With ElastiCache, you can configure Memcached clusters in multiple AZs, and the service will handle failover automatically.

Here's an example of how to create a Memcached cluster in multiple AZs using ElastiCache:

aws elasticache create-cache-cluster --cache-cluster-id my-memcached-cluster \
--cache-node-type cache.m3.medium \
--engine memcached \
--num-cache-nodes 2 \
--preferred-availability-zones us-east-1a,us-east-1b \
--auto-failover-enabled \
--cache-subnet-group-name my-subnet-group \
--security-group-ids my-security-group

In the above command, we're creating a Memcached cluster with two nodes in two different availability zones (us-east-1a and us-east-1b). The --auto-failover-enabled flag enables automatic failover, and the --cache-subnet-group-name specifies the subnet group where the nodes will be deployed. The --security-group-ids parameter specifies the security group associated with the nodes.

Note that using a managed service like ElastiCache can save you the hassle of managing your own Memcached deployment and also provides additional features such as automatic scaling, security, and monitoring.