Regression between 0.12.24 and 0.12.29 on ec2metadata calls

[ghost]

This issue was originally opened by @lifeofguenter as hashicorp/terraform#25835. It was migrated here as a result of the provider split. The original body of the issue is below.

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It seems like 0.12.29 is doing a lot more requests to ec2metadata than 0.12.24 to a point where we are being rate limited (see: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/instancedata-data-retrieval.html)

It is advised:

• cache results
• implement retry with back-off

Logs:

[2020-08-13T08:20:39.133Z] 2020/08/13 08:20:38 [INFO] Setting AWS metadata API timeout to 100ms
[2020-08-13T08:20:39.702Z] 2020/08/13 08:20:39 [INFO] Ignoring AWS metadata API endpoint at default location as it doesn't return any instance-id
[2020-08-13T08:20:39.712Z] 2020/08/13 08:20:39 [INFO] Attempting to use session-derived credentials
[2020-08-13T08:20:40.293Z] 2020/08/13 08:20:40 [INFO] Ignoring AWS metadata API endpoint at default location as it doesn't return any instance-id
[2020-08-13T08:20:40.304Z] 2020/08/13 08:20:40 [INFO] Attempting to use session-derived credentials

[gdavison]

This has been resolved in v4.0 of the AWS provider. If you see this issue again in newer versions, please open a new issue

[github-actions]

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