如何使用 python 获取 AWS 实例总大小 memory？

Question

I want to run a python startup script inside AWS instance in which I want to get the total memory size selected during instance creation.

I have tried free -h , grep MemTotal /proc/meminfo commands. But, the problem with these commands is, I get some less amount of RAM than the actual memory size I selected while creating an instance (due to system use maybe). I want to get the exact memory size I selected while creating an instance. eg, "2 GB" for "t2.small", "4 GB" for "c5.large",etc.

Also, there is no metadata URL available to get AWS instance memory size.

Is there any way to do that?

Answer 1

I haven't done this myself, but I think the process might be something like:

client = boto3.client('ec2')

type = client.describe_instance_attribute(Attribute='instanceType', InstanceId='YOUR_ID' )

details = client.describe_instance_types( InstanceTypes=[ type ] )

memory = details['InstanceTypes']['MemoryInfo']['SizeInMiB']

You'll need to give the instance the right IAM permissions to get the data (it's not the same as the http://169.254.169.254 metadata).

You can also get the instance type from http://169.254.169.254/2020-10-27/meta-data/instance-type/ but I'm trying to go for a fully python solution with boto3.