Available RDS NetworkInterface is exist although I deleted RDS instance

Question

Hello, 
I got a problem of RDS Network Interface that didn't be deleted automatically after deleting RDS.
The Network Interfaces’ request Id is Amazon-rds.   
I tested that if I delete RDS, the Network interface, which is attached to the RDS, should be deleted. 
However, I don’t know what happened, I found network interfaces are as status of “available”, but all my RDS are working with other network interfaces. There is no stopped RDS in my region.
Therefore, I assume those network interface isn’t used.

Can I remove those network interfaces without any impact of my running RDS instances? 
Also, How the ‘available’ network interfaces are existed without attached RDS?

Answer

Hello Hessu,

Yes! If you see the "status: available" means it's is not used by any of the resource and can be removed.
 
https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DescribeNetworkInterfaces.html#API_DescribeNetworkInterfaces_RequestParameters

=> status - The status of the network interface. If the network interface is not attached to an instance, the status is available; if a network interface is attached to an instance the status is in-use.

Regards,
CK

Available RDS NetworkInterface is exist although I deleted RDS instance

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