Couchbase 5.1.1 Centos install error

Hi All, I was trying to manually install the Couchbase 5.1.1 to AWS linux server. based on “https://docs.couchbase.com/server/4.1/install/awi-manual.html” this link. every step no error but when i try to Configure the instance to use the Amazon EBS directory for storage: I got the unable to connect host http:localhost:8091 error.


for security group, i opened all traffic. pls kindly check the attachement.
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There is any config. i need to change?

When i connect to couchbase console, the connection was refused. Pls help mee. Thanks