Cannot modify the instance class because there are no instances of the requested class available in the current instance’s availability zone

When you change the instance type of an AWS RDS instance, the availability zone of the instance has to have available capacity of the selected type. Some older availability zones (us-east-1a) have more old instance types than new types available. If the instance type you selected is not available in the current zone of the […]

“incompatible-network” error when launching an AWS RDS instance

When the AWS subnet has no enough IP addresses Terraform displays the following error message: * aws_db_instance.default: unexpected state ‘incompatible-network’, wanted target ‘available, storage-optimization’. last error: %!s(<nil>) Make sure the subnet has enough available IP addresses.

The specified Security Group and Parameter Group are not set in the RDS instance

If the Terraform apply execution times out during the RDS instance creation, the specified Security Group and Parameter Group is not set in the RDS instance. The solution is to set the timeout in the aws_db_instance resource. When a multi-az RDS instance is launched from a snapshot, the process can take more than 55 minutes. The default […]

SQL Server AWS RDS instance ALARM FreeableMemory <=... MB

The SQL database servers use the available memory for caching to speed up the database operation. If we do not restrict the SQL database server memory usage, the operating system will not have enough memory to run. This setting is also necessary for an AWS RDS instance, otherwise, you will get the alert ALARM FreeableMemory <=… MB In AWS […]

Migrate databases to and from AWS RDS instances

Amazon Web Services do not provide tools to migrate data to, from and between AWS RDS instances. There is a free utility that can do the job. SQL Server Management Studio (SSMS) Install Microsoft SQL Server Management Studio (SSMS), because the utility uses libraries from it. Download the installer for free from https://msdn.microsoft.com/en-us/library/mt238290.aspx SQL Azure Migration […]