外部连接mysql docker容器异常

为了方便，使用python测试连接mysql容器

脚本内容非常简单

#!/usr/bin/python3
import pymysql

conn=pymysql.connect(host="localhost",user="root",port=,password="",database="mydb")
cursor=conn.cursor()
cursor.execute("select count(*) from mydb.t")
cursor.close()
conn.close()

执行上述脚本后，发生以下异常

Traceback (most recent call last):
  File "./p.py", line , in <module>
    conn=pymysql.connect(host="localhost",user="root",port=,password="",database="mydb")
  File "/usr/local/lib64/python3.6/site-packages/pymysql/__init__.py", line , in Connect
    return Connection(*args, **kwargs)
  File "/usr/local/lib64/python3.6/site-packages/pymysql/connections.py", line , in __init__
    self.connect()
  File "/usr/local/lib64/python3.6/site-packages/pymysql/connections.py", line , in connect
    self._get_server_information()
  File "/usr/local/lib64/python3.6/site-packages/pymysql/connections.py", line , in _get_server_information
    packet = self._read_packet()
  File "/usr/local/lib64/python3.6/site-packages/pymysql/connections.py", line , in _read_packet
    packet_header = self._read_bytes()
  File "/usr/local/lib64/python3.6/site-packages/pymysql/connections.py", line , in _read_bytes
    CR.CR_SERVER_LOST, "Lost connection to MySQL server during query")
pymysql.err.OperationalError: (, 'Lost connection to MySQL server during query')

从错误信息看，是不能够正常连接到OMC，刚开始怀疑是pymysql.connect方法中传递的参数不正确，但无论怎么修改，始终出现2013的异常，后来查看mysql配置文件，发现存在一条配置

bind_address=127.0.0.1

改参数限制了mysql不能被远程访问，所以在容器外部没法访问到容器内部的mysql，造成2013异常，注释掉改配置，重启mysql docker容器，访问正常

另外如果将改配置对应的ip地址改为宿主机地址，还会出现如下异常

Traceback (most recent call last):
  File "./p.py", line , in <module>
    conn=pymysql.connect(host="localhost",user="root",port=,password="",database="mydb")
  File "/usr/local/lib64/python3.6/site-packages/pymysql/__init__.py", line , in Connect
    return Connection(*args, **kwargs)
  File "/usr/local/lib64/python3.6/site-packages/pymysql/connections.py", line , in __init__
    self.connect()
  File "/usr/local/lib64/python3.6/site-packages/pymysql/connections.py", line , in connect
    raise exc
pymysql.err.OperationalError: (, "Can't connect to MySQL server on 'localhost' ([Errno 111] Connection refused)")

且mysql未正常启动，错误日志中有如下信息

--15T02::.769286Z  [Warning] [MY-] [Server] CA certificate ca.pem is self signed.
--15T02::.791952Z  [ERROR] [MY-] [Server] Can't start server: Bind on TCP/IP port: Cannot assign requested address
--15T02::.791960Z  [ERROR] [MY-] [Server] Do you already have another mysqld server running on port:  ?
--15T02::.792191Z  [ERROR] [MY-] [Server] Aborting
--15T02::.855205Z  [System] [MY-] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.)  MySQL Community Server - GPL.