Connection error while connecting linode mongodb server

Question

I have installed mogodb linode "mongodb-app" and its running.. created user and collections and able to access it from shell now trying to connect to the server from my local but getting server timeout '''

pymongo.errors.ServerSelectionTimeoutError: 170.187.248.15:27017: timed out, Timeout: 30s, Topology Description: <TopologyDescription id: 6218a8cccb94c35a2569ce55, topology_type: Single, servers: [<ServerDescription ('170.187.248.15', 27017) server_type: Unknown, rtt: None, error=NetworkTimeout('170.187.248.15:27017: timed out')>]>

default_config = {'MONGODB_SETTINGS': {
#Local DB
'db': 'test_db',
'host': 'localhost',
'port': 27017

#linode "mongodb-app"
'db': '<db name>',
'host': '<server ip>',
'port': 27017,
'username': '<db user>,
'password': '<db password>',
'authentication_source': 'admin'
}

''' I have followed couple of steps: '''

1. updated /etc/mongod.conf from the server
    net:
    port: 27017
    bindIp:0.0.0.0

'''

2. sudo ufw status
    sudo: unable to resolve host 170-187-248-15
    Status: active

    To                         Action      From
    --                         ------      ----
    22                         ALLOW       Anywhere
    27017                      ALLOW       0.0.0.0
    22 (v6)                    ALLOW       Anywhere (v6)

but still facing the same error

Answer 1

On your linux server where mongodb is running, run these two commands:

iptables -A INPUT -s <ip-address-of-your-app> -p tcp --destination-port 27017 -m state --state NEW,ESTABLISHED -j ACCEPT

iptables -A OUTPUT -d <ip-address-of-your-app> -p tcp --source-port 27017 -m state --state ESTABLISHED -j ACCEPT

Taken from https://docs.mongodb.com/manual/tutorial/configure-linux-iptables-firewall/#traffic-to-and-from-mongod-instances