ClientConnectorError: Cannot connect to host <host>:8182 ssl:default [Connect call failed ('<ip-address>', 8182)]

Question

Just tried below mentioned code to check my Amazon Neptune service, it's throwing this error:

ClientConnectorError: Cannot connect to host <host>:8182 ssl:default [Connect call failed ('<ip-address>', 8182)]

from __future__  import print_function  # Python 2/3 compatibility

from gremlin_python import statics
from gremlin_python.structure.graph import Graph
from gremlin_python.process.graph_traversal import __
from gremlin_python.process.strategies import *
from gremlin_python.driver.driver_remote_connection import DriverRemoteConnection

graph = Graph()
remoteConn = DriverRemoteConnection('wss://<host>','g')

g = graph.traversal().withRemote(remoteConn)

print(g.V().limit(2).toList())
remoteConn.close()

Does anybody know the solution? Thanks

Answer 1

<host> is a placeholder that you need to replace with the name of the host that runs Gremlin Server. If your python client runs on the same host, you can replace <host> by localhost.

Also note that you can only use url's starting with wss:// if secure socket layer is configured on Gremlin Server, otherwise use a url starting with ws://.

Answer 2

Remember when you connect locally you should jump into a bastion host, and change Neptune DNS locally to point locally eg.

127.0.0.1 neptune.dns.aws.com

Then you can call the curl command to get Neptune's response when you are hooked on the AWS network.

curl -X POST --data-binary 'query=select ?s ?p ?o where {?s ?p ?o} limit 10' http://neptune-dns.neptune.amazonaws.com:8182/sparql

Answer 3

hope you have solved this already yourself. But what the AWS docs say you need this Type of string: remoteConn = DriverRemoteConnection('wss://"your cluster endpoint":8182/gremlin','g')

Then presuming that you have a service connected to the same VPC or in a VPC that can communicate with the VPC of the Neptune DB. The service you want to connect to the Neptune_DB need to be able to access the Security group of the Neptune DB E.G add a Inbound rules to the security group of the Neptune_DB to allow all traffic, or at minimum TCP(as wss:// uses TCP), from the security group of the service.