使用 SSH 隧道时无法通过套接字错误连接到本地 MySQL 服务器

Question

我正在尝试使用 dplyr 连接到远程数据库，我通常通过 ssh 隧道进行查询。

我首先像下面这样设置一个 ssh 隧道：

alias tunnel_ncg='ssh -fNg -L 3307:127.0.0.1:3306 mysqluser@myhost mysql5 -h 127.0.0.1:3306 -P 3307 -u mysqluser -p mypassword'

此时我可以通过连接到 localhost:3307 来访问数据库。例如：

mysql -h '127.0.0.1' -P 3307 -u mysqluser

如果我尝试通过 dplyr 访问同一个数据库，我会收到一个错误，抱怨它无法连接到本地 MySQL 套接字：

> conDplyr = src_mysql(dbname = "mydb", user = "mysqluser", password = "mypassword", host = "localhost", port=3307)
Error in .local(drv, ...) : 
  Failed to connect to database: Error: Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)

我的理解是 RMySQL/dplyr 正试图在本地计算机中寻找套接字文件，但他们实际上应该在远程服务器中寻找它。有没有办法解决这个问题或解决方法？

更新：

如果我尝试通过 dbConnect/RMySQL 连接，连接工作正常：

> dbConnect(dbDriver("MySQL"), user="mysqluser", password="mypassword", dbname="mydb", host="127.0.0.1", port=3307)
<MySQLConnection:0,1>

Answer 1

用 IP 地址 (127.0.0.1) 替换 localhost 听起来很愚蠢解决了问题。

src_mysql(
    dbname = "mydb", user = "mysqluser", password = "mypassword",
    host = "127.0.0.1", port=3307)

有关解释，请查看 MySQL documentation:

On Unix, MySQL programs treat the host name localhost specially, in a way that is likely different from what you expect compared to other network-based programs.

For connections to localhost, MySQL programs attempt to connect to the local server by using a Unix socket file. This occurs even if a --port or -P option is given to specify a port number.

To ensure that the client makes a TCP/IP connection to the local server, use --host or -h to specify a host name value of 127.0.0.1, or the IP address or name of the local server.

使用 SSH 隧道时无法通过套接字错误连接到本地 MySQL 服务器

Can't connect to local MySQL server through socket error when using SSH tunel

r

ssh-tunnel

rmysql

dplyr