amazon web services - Why does AWS CLI need access/secret key? -

if assigned iam role ec2 instance, , want use aws cli instance, why require me put in access/secret key, isn't kind of redundant?

you don't need it. as readme says:

the quickest way started run aws configure command:

that doesn't mean it's way.

for iam roles, don't need anything, it'll work correctly out of box:

the final option credentials highly recommended if using aws-cli on ec2 instance. iam roles great way have credentials installed automatically on instance. if using iam roles, aws-cli find them , use them automatically.

(also readme).