OperationalError：（OperationalError）（2003，“无法连接到'192.168.129.139'（111）”上的MySQL服务器）无无

Question

我想在运行12.04的Ubuntu机器上使用mysql创建远程数据库。

它有一个启用了远程登录并且没有密码的root用户。我已经启动了服务器。输出的

sudo netstat -tap | grep mysql 

显示

tcp  0  0 localhost:mysql   *:*      LISTEN  13246/mysqld 

我已经创建了一个称为nwtopology使用数据库（如所提到的根不具有密码尚未。）

create database nwtopology 
grant all privileges on *.* to [email protected] 
FLUSH PRIVILEGES; 

从同时运行Ubuntu 12.04的客户端机器我使用python脚本使用sqlal连接到远程mysql数据库chemy。

from pox.core import core 
import pox.openflow.libopenflow_01 as of 
import re 
import datetime 
import time 
from sqlalchemy import create_engine, ForeignKey 
from sqlalchemy import Column, Date, Integer, String 
from sqlalchemy.ext.declarative import declarative_base 
from sqlalchemy.orm import relationship, backref 
from sqlalchemy import create_engine 
from sqlalchemy.orm import sessionmaker 
from sqlalchemy.sql.expression import exists 

log = core.getLogger() 
engine = create_engine('mysql://[email protected]/nwtopology', echo=False) 
Base = declarative_base() 
Session = sessionmaker(bind=engine) 
session = Session() 

class SourcetoPort(Base): 
    """""" 
    __tablename__ = 'source_to_port' 
    id = Column(Integer, primary_key=True) 
    port_no  = Column(Integer) 
    src_address = Column(String,index=True) 

    #----------------------------------------- 
    def __init__(self, src_address,port_no): 
     """""" 
     self.src_address = src_address 
     self.port_no  = port_no 

create_engine（）调用失败，出现以下错误。

POX 0.1.0 (betta)/Copyright 2011-2013 James McCauley, et al. 
Traceback (most recent call last): 
    File "/home/karthik/ms_thesis/pox/pox/boot.py", line 89, in do_import2 
    __import__(name, globals(), locals()) 
    File "/home/karthik/ms_thesis/pox/custom/tutorial.py", line 39, in <module> 
    Base.metadata.create_all(engine) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/schema.py", line 2515, in create_all 
    tables=tables) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/base.py", line 2230, in _run_visitor 
    conn = self.contextual_connect(close_with_result=False) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/base.py", line 2340, in contextual_connect 
    self.pool.connect(), 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/pool.py", line 210, in connect 
    return _ConnectionFairy(self).checkout() 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/pool.py", line 371, in __init__ 
    rec = self._connection_record = pool._do_get() 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/pool.py", line 697, in _do_get 
    con = self._create_connection() 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/pool.py", line 174, in _create_connection 
    return _ConnectionRecord(self) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/pool.py", line 256, in __init__ 
    self.connection = self.__connect() 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/pool.py", line 316, in __connect 
    connection = self.__pool._creator() 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/strategies.py", line 80, in connect 
    return dialect.connect(*cargs, **cparams) 
    File "/usr/lib/python2.7/dist-packages/sqlalchemy/engine/default.py", line 280, in connect 
    return self.dbapi.connect(*cargs, **cparams) 
    File "/usr/lib/python2.7/dist-packages/MySQLdb/__init__.py", line 81, in Connect 
    return Connection(*args, **kwargs) 
    File "/usr/lib/python2.7/dist-packages/MySQLdb/connections.py", line 187, in __init__ 
    super(Connection, self).__init__(*args, **kwargs2) 
OperationalError: (OperationalError) (2003, "Can't connect to MySQL server on '192.168.129.139' (111)") None None 

我想不通为什么会发生这种情况？

Answer 1

看起来像mysql被配置为仅侦听本地主机。

您可以通过在客户端计算机上运行telnet 192.168.129.139 3306来进行测试。

最可能的原因 - mysqld被配置为这样做。

请尽量遵守Configuration step described here：

编辑/etc/mysql/my.cnf文件到MySQL配置侦听来自网络主机的连接，更改绑定地址指令的服务器的IP地址。例如用适当的地址替换192.168.0.5。如果没有这样的条目 - 取消注释或创建新行。

bind-address   = 192.168.0.5 

然后重启mysqld

​​

然后用telnet或通过再次运行你的应用程序进行测试。另外netstat会有mysqld的第二项。