linux mysql 远程无法连接ERROR 2003 (HY000): Can't '127.0.0.1' (111) linux

Posted 2023-03-20

linux mysql棘手的问题。。
./mysql -hlocalhost -uroot -pxiaodi
能连上
./mysql -h127.0.0.1 -uroot -pxiaodi
却连不上
这里是不是防火墙阻挡？理论上来说./mysql -h192.168.1.1 -uroot -pxiaodi 需要穿过防火墙 192.168.1.1 为真实ip

就想问你们./mysql -h127.0.0.1 -uroot -pxiaodi 需要本机防火墙验证吗？

前提是 已经有个root 任意主机的用户了。。

还有 my.ini 是不指 linux下的my.cnf文件???
那么-h localhost呢？需要防火墙认证吗？

如果加入-h参数是需要通过防火墙的

vi /etc/sysconfig/iptables
写入以下内容：
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 3306 -j ACCEPT

保存后重启iptables
service iptables restart

或直接关掉 防火墙 service iptables stop

如果可以连接mysql，说明是防火墙！

my.ini 是不指 linux下的my.cnf文件 是的 参考技术A 可以考虑:
1, 使用-uroot -hlocalhost 登录mysql;
2, select Host,User,Password from mysql.user; 来查看mysql.user表中是否存在Host为127.0.0.1 的注册root用户,若没有请添加.若有请查看Password字段是否为空;

PS: 127.0.0.1 一般来说不需要本地IPtables的参与即可实现通信.具体需要您提供IPtables的样本才能够实现. 也可以通过关闭iptables来检查是否被防火墙阻断; 参考技术B root 用户在USER表的HOST权限是什么？是%嘛

Mysql无法远程连接解决方案

前言

Mysql 版本：5.7.23
操作系统：Linux
问题描述：
只能通过Linux系统账号Root命令行进入数据库，无法使用JDBC，远程连接工具进入数据库。
报错：ERROR 1698 (28000): Access denied for user ‘root‘@‘localhost‘
这个问题明显就是没有开放远程连接授权，所以导致只能使用Linux的Root账号登录。

解决流程

1.找到/etc/mysql/mysql.conf.d/mysqld.cnf文件，在[mysqld]最后面加skip-grant-tables

#
# The MySQL database server configuration file.
#
# You can copy this to one of:
# - "/etc/mysql/my.cnf" to set global options,
# - "~/.my.cnf" to set user-specific options.
# 
# One can use all long options that the program supports.
# Run program with --help to get a list of available options and with
# --print-defaults to see which it would actually understand and use.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html

# This will be passed to all mysql clients
# It has been reported that passwords should be enclosed with ticks/quotes
# escpecially if they contain "#" chars...
# Remember to edit /etc/mysql/debian.cnf when changing the socket location.

# Here is entries for some specific programs
# The following values assume you have at least 32M ram

[mysqld_safe]
socket      = /var/run/mysqld/mysqld.sock
nice        = 0

[mysqld]
#
# * Basic Settings
#
user        = mysql
pid-file    = /var/run/mysqld/mysqld.pid
socket      = /var/run/mysqld/mysqld.sock
port        = 3306
basedir     = /usr
datadir     = /var/lib/mysql
tmpdir      = /tmp
lc-messages-dir = /usr/share/mysql
skip-external-locking
# 加入的内容,开启跳过权限校验
skip-grant-tables
#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
bind-address        = 127.0.0.1
#
# * Fine Tuning
#
key_buffer_size     = 16M
max_allowed_packet  = 16M
thread_stack        = 192K
thread_cache_size       = 8
# This replaces the startup script and checks MyISAM tables if needed
# the first time they are touched
myisam-recover-options  = BACKUP
#max_connections        = 100
#table_open_cache       = 64
#thread_concurrency     = 10
#
# * Query Cache Configuration
#
query_cache_limit   = 1M
query_cache_size        = 16M
#
# * Logging and Replication
#
# Both location gets rotated by the cronjob.
# Be aware that this log type is a performance killer.
# As of 5.1 you can enable the log at runtime!
#general_log_file        = /var/log/mysql/mysql.log
#general_log             = 1
#
# Error log - should be very few entries.
#
log_error = /var/log/mysql/error.log
#
# Here you can see queries with especially long duration
#slow_query_log     = 1
#slow_query_log_file    = /var/log/mysql/mysql-slow.log
#long_query_time = 2
#log-queries-not-using-indexes
#
# The following can be used as easy to replay backup logs or for replication.
# note: if you are setting up a replication slave, see README.Debian about
#       other settings you may need to change.
#server-id      = 1
#log_bin            = /var/log/mysql/mysql-bin.log
expire_logs_days    = 10
max_binlog_size   = 100M
#binlog_do_db       = include_database_name
#binlog_ignore_db   = include_database_name
#
# * InnoDB
#
# InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/.
# Read the manual for more InnoDB related options. There are many!
#
# * Security Features
#
# Read the manual, too, if you want chroot!
# chroot = /var/lib/mysql/
#
# For generating SSL certificates I recommend the OpenSSL GUI "tinyca".
#
# ssl-ca=/etc/mysql/cacert.pem
# ssl-cert=/etc/mysql/server-cert.pem
# ssl-key=/etc/mysql/server-key.pem

保存后，重启服务sudo service mysql restart.

2.无验证进入mysql数据库修改user表中root账号信息，flush privileges;

[email protected]:~$ mysql
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 2
Server version: 5.7.23-0ubuntu0.18.04.1 (Ubuntu)

Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type ‘help;‘ or ‘h‘ for help. Type ‘c‘ to clear the current input statement.

mysql> use mysql
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> update mysql.user set authentication_string=password(‘账号密码‘) where user=‘root‘;
Query OK, 0 rows affected, 1 warning (0.03 sec)
Rows matched: 3  Changed: 0  Warnings: 1

mysql> update user set plugin="mysql_native_password";
Query OK, 1 row affected (0.00 sec)
Rows matched: 7  Changed: 1  Warnings: 0

mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

mysql> quit
Bye

3./etc/mysql/mysql.conf.d/mysqld.cnf文件，去掉skip-grant-tables，开启校验

4.重启服务

sudo service mysql restart;

至此就搞定了，使用jdbc、非Linuxroot账号都可以登录了。