客户端到节点加密后，Datastax Opscenter 5.1.1无法连接到群集

我正在尝试在cassandra上设置节点间和客户端加密。我设置了一个小型ca，生成了证书，分发了证书，并配置了节点以使用它们。

添加“ --ssl”后，节点间加密会直接工作，cqlsh。

但是我无法设置OpsCenter（运行5.1.1）。两个问题：

1. 我按要求为我添加了/etc/opscenter/cassandra_ca.pem的ca文件路径。即使没有设置用于客户端验证的标记，我也无法保存集群，直到添加密钥库为止-我也找不到任何有关密钥库的文档。由于OpsCenter是python，因此这些显然不是cassandra的jks密钥库。

我想这意味着，各个节点将自己的证书提交给opscenter，该证书将针对ca-store进行验证。

2. 尝试连接会在opscenterd.log中给我一个错误：

2015-05-26 10:20:49+0000 []  INFO: Using SSL when checking thrift connection: /etc/cassandra/cassandra_ca.crt, client_pem=None, client_key=None, validate=True
2015-05-26 10:20:49+0000 []  INFO: Starting factory <opscenterd.ThriftService.NoReconnectCassandraClientFactory instance at 0x7fa4868c03b0>
2015-05-26 10:20:49+0000 [] Unhandled Error
        Traceback (most recent call last):
          File "/usr/share/opscenter/lib/py-debian/2.7/amd64/twisted/python/log.py", line 84, in callWithLogger
            return callWithContext({"system": lp}, func, *args, **kw)
          File "/usr/share/opscenter/lib/py-debian/2.7/amd64/twisted/python/log.py", line 69, in callWithContext
            return context.call({ILogContext: newCtx}, func, *args, **kw)
          File "/usr/share/opscenter/lib/py-debian/2.7/amd64/twisted/python/context.py", line 59, in callWithContext
            return self.currentContext().callWithContext(ctx, func, *args, **kw)
          File "/usr/share/opscenter/lib/py-debian/2.7/amd64/twisted/python/context.py", line 37, in callWithContext
            return func(*args,**kw)
        --- <exception caught here> ---
          File "/usr/share/opscenter/lib/py-debian/2.7/amd64/twisted/internet/epollreactor.py", line 220, in _doReadOrWrite
            why = selectable.doWrite()
          File "/usr/share/opscenter/lib/py-debian/2.7/amd64/twisted/internet/tcp.py", line 664, in doConnect
            self._connectDone()
          File "/usr/share/opscenter/lib/py-debian/2.7/amd64/twisted/internet/ssl.py", line 160, in _connectDone
            self.startTLS(self.ctxFactory)
          File "/usr/share/opscenter/lib/py-debian/2.7/amd64/twisted/internet/tcp.py", line 561, in startTLS
            if Connection.startTLS(self, ctx, client):
          File "/usr/share/opscenter/lib/py-debian/2.7/amd64/twisted/internet/tcp.py", line 402, in startTLS
            self.socket = SSL.Connection(ctx.getContext(), self.socket)
          File "/usr/lib/python2.7/dist-packages/opscenterd/SslUtils.py", line 54, in getContext

          File "/usr/lib/python2.7/dist-packages/OpenSSL/SSL.py", line 303, in load_verify_locations
            raise TypeError("cafile must be None or a byte string")
        exceptions.TypeError: cafile must be None or a byte string

2015-05-26 10:20:49+0000 []  INFO: <twisted.internet.ssl.Connector instance at 0x7fa4868c05f0> will retry in 2 seconds
2015-05-26 10:20:49+0000 []  INFO: Unhandled error in Deferred:
2015-05-26 10:20:49+0000 [] Unhandled Error
        Traceback (most recent call last):
        Failure: twisted.internet.error.ConnectError: An error occurred while connecting: [Failure instance: Traceback (failure with no frames): <type 'exceptions.TypeError'>: cafile must be None or a byte string
        ].            ].

有什么提示吗？

预先感谢，扬