Not using Active/standby deployment mode for MQ Brokers can have an impact on availability of MQ Broker.
This configuration setting only applies to the ActiveMQ engine and the multi-az configuration can only be enabled upon broker creation. To create a new broker, follow the steps below.
In AWS Console -
In Terraform -
References:
https://docs.aws.amazon.com/amazon-mq/latest/developer-guide/active-standby-broker-deployment.html
https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/mq_broker#deployment_mode