DataStax Python Cassandra 驱动程序错误地发现本地主机上的 Cassandra

我有这个小大学项目，我开发了一个简单的 Python 应用程序，带有 Bokeh 前端和 Cassandra 后端。我一直在对它进行原型设计并在单个 Cassandra 节点上进行开发，然后扩展到三个节点，一个是本地节点，两个是虚拟节点。因此，开发是在本地主机上进行的，然后我迁移到使用名为 vboxnet0 的主机专用网络和 IP 地址：

• 192.168.56.1 为主
• 192.168.56.101/102 为奴隶。

Cassandra 版本为 3.11.1
Bokeh 服务器版本为 0.12.10（在 Tornado 4.4.3 上运行）

我相应地更改了代码，因此我的应用程序代码开头为：

from cassandra.cluster import Cluster
from cassandra.auth import PlainTextAuthProvider
from cassandra.query import dict_factory`

def pandas_factory(colnames, rows):
    return pd.DataFrame(rows, columns=colnames)
auth_provider = PlainTextAuthProvider(username='', password='')
cluster = Cluster(contact_points=['192.168.56.1'], port=9042, auth_provider=auth_provider)
session = cluster.connect()
session.row_factory = pandas_factory
session.default_fetch_size = None

Cassandra不在本地主机上运行：

username@hostname:~> cqlsh
Connection error: ('Unable to connect to any servers', {'127.0.0.1': error(111, "Tried connecting to [('127.0.0.1', 9042)]. Last error: Connection refused")})

然而 Python 驱动程序以某种方式认为它在 127.0.0.1 上发现了一个 Cassandra 主机并尝试连接到它：

username@hostname:~/Folder/subfolder> bokeh serve Appname > ~/bokeh.output
2017-11-22 19:24:49,230 Starting Bokeh server version 0.12.10 (running on Tornado 4.4.3)
2017-11-22 19:24:49,233 Bokeh app running at: http://localhost:5006/Appname
2017-11-22 19:24:49,233 Starting Bokeh server with process id: 5819
2017-11-22 19:25:03,281 Using datacenter 'datacenter1' for DCAwareRoundRobinPolicy (via host '192.168.56.1'); if incorrect, please specify a local_dc to the constructor, or limit contact points to local cluster nodes
2017-11-22 19:25:03,281 New Cassandra host <Host: 127.0.0.1 datacenter1> discovered
2017-11-22 19:25:03,282 Found multiple hosts with the same rpc_address (127.0.0.1). Excluding peer 192.168.56.101
2017-11-22 19:25:03,368 Failed to create connection pool for new host 127.0.0.1:
Traceback (most recent call last):
  File "cassandra/cluster.py", line 2343, in cassandra.cluster.Session.add_or_renew_pool.run_add_or_renew_pool (cassandra/cluster.c:44919)
  File "cassandra/pool.py", line 332, in cassandra.pool.HostConnection.__init__ (cassandra/pool.c:6757)
  File "cassandra/cluster.py", line 1119, in cassandra.cluster.Cluster.connection_factory (cassandra/cluster.c:16094)
  File "cassandra/connection.py", line 330, in cassandra.connection.Connection.factory (cassandra/connection.c:5963)
  File "/usr/lib64/python3.6/site-packages/cassandra/io/asyncorereactor.py", line 307, in __init__
    self._connect_socket()
  File "cassandra/connection.py", line 369, in cassandra.connection.Connection._connect_socket (cassandra/connection.c:7477)
ConnectionRefusedError: [Errno 111] Tried connecting to [('127.0.0.1', 9042)]. Last error: Connection refused
2017-11-22 19:25:03,403 Host 127.0.0.1 has been marked down
2017-11-22 19:25:04,406 Error attempting to reconnect to 127.0.0.1, scheduling retry in 2.0 seconds: [Errno 111] Tried connecting to [('127.0.0.1', 9042)]. Last error: Connection refused
2017-11-22 19:25:06,414 Error attempting to reconnect to 127.0.0.1, scheduling retry in 4.0 seconds: [Errno 111] Tried connecting to [('127.0.0.1', 9042)]. Last error: Connection refused
2017-11-22 19:28:14,994 Error attempting to reconnect to 127.0.0.1, scheduling retry in 8.0 seconds: [Errno 111] Tried connecting to [('127.0.0.1', 9042)]. Last error: Connection refused
2017-11-22 19:28:16,489 Host 127.0.0.1 may be up; will prepare queries and open connection pool
2017-11-22 19:28:16,808 Failed to create connection pool for new host 127.0.0.1:

然后它继续下去。从正面看，它看起来不错，应用程序可以正常工作，并且 192.168.56.1 被正确查询，但这只是令人讨厌的东西不对，我不知道这是错误还是我自己的错。