I'm trying to update lambda runtime, using AWS CLI, with the following command:
aws lambda update-function-configuration --function-name <func_name> --runtime nodejs4.3
Unknown options: --runtime, nodejs4.3
aws-cli/1.9.6 Python/3.5.0 Windows/7 botocore/1.3.6
The option is available from aws cli 1.10.19 so you need to upgrade at least to this version of newer
lambda: Added support for setting the function runtime as nodejs4.3, as well as updating function configuration to set the runtime.