RDS InvalidParameterCombination - Combination working before

Question

When trying to create a DB instance with Terraform, I'm getting the following error:

> Creating RDS DB Instance (xxxxx): InvalidParameterCombination: RDS does not support creating a DB instance with the following combination: DBInstanceClass=db.t2.micro, Engine=postgres, EngineVersion=12.17, LicenseModel=postgresql-license. For supported combinations of instance class and database engine version, see the documentation.

I have successfully created PostgreSQL instances with this combination (db.t2.micro, PostgreSQL 12.17) numerous times in the past, and I still have several of them running smoothly. According to the documentation, this setup should be supported, as t2.micro instances are compatible with PostgreSQL versions up to 12.x.

Additionally, the Terraform code I am using has been tested and was fully functional as of a month ago. I am running the same code again, but with a different instance name, to create another instance identical to the previous one.

Any tips? 
Thanks

Accepted Answer

Hello.

Can you check "db.t2.micro" by running the command below?  
By the way, I checked "us-east-1" and "us-east-2", but "t2.micro" did not appear in the output.  
In other words, "t2.micro" cannot be used.  
I think the documentation is probably not up to date.  
Therefore, I think it is necessary to use something like "t3", which is the successor of "t2.micro".  
https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/Concepts.DBInstanceClass.html#Concepts.DBInstanceClass.RegionSupport  
```
aws rds describe-orderable-db-instance-options --engine postgres --engine-version 12.17 --query "*[].{DBInstanceClass:DBInstanceClass,StorageType:StorageType}|[?StorageType=='gp2']|[].{DBInstanceClass:DBInstanceClass}" --output text --region "your used region" | grep "t2"
```

If you have an RDS that uses “t2.micro”, you should have received an email from AWS stating “[Action required] End-of-life date is approaching for Amazon RDS for PostgreSQL database instances on M4, R4 , T2 instance types” from AWS.  
The email stated that starting March 11, 2024, you will no longer be able to launch RDS instances using "t2".

RDS InvalidParameterCombination - Combination working before

Relevant content