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目前顯示的是 1月, 2021的文章

centos 8 modify ssh port number

 1. 開放port number sudo firewall-cmd --zone=public --permanent --remove-port=8090/tcp sudo firewall-cmd --reload 2. 修改或關閉selinux,這部分我們已經關了,所以不用管他。 3. 更改sshd port number  把 /etc/ssh/sshd_config 內的 Port 22 改成 8090 儲存檔案後 service sshd restart。

connect to MySQL server remotely

  ERROR 2003 (HY000): Can’t connect to MySQL server on ‘x.x.x.x’ (xxx) 原因為安全性問題, 測試方法:  1. 確認服務開啟  ps -e | grep mysql netstat -n | grep mysql 2. 關閉selinux  3. 關閉firewalld service firewalld stop 或者開啟port # 永久將 mysql 服務從 public 區域中移除 sudo firewall-cmd --zone=public --permanent --remove-port=3306/tcp # 重新載入設定 sudo firewall-cmd --reload # 永久關閉 tcp 的 3306 連接埠 sudo firewall-cmd --zone=public --permanent --remove-port= 3306/tcp 4. 確認root grant option權限 mysql> grant all privileges on *.* to 'root'@'localhost' WITH GRANT OPTION; mysql> grant all privileges on *.* to 'root'@'%' ; ERROR 1410 (42000): You are not allowed to create a user with GRANT (新的mysql: 不能對所有主機的帳號授予) mysql> grant all privileges on *.* to 'root'@'localhost' ; Query OK, 0 rows affected (0.00 sec) mysql> flush privileges; Query OK, 0 rows affected (0.00 sec) 5. 建立遠端連線帳號 mysql> CREATE USER 'sqmc'@'x.x.x.x' IDENTIFIED BY 'newpassword'; Qu

restart mysql

  mysql> show variables like 'datadir''; +---------------+-----------------+ | Variable_name | Value           | +---------------+-----------------+ | datadir       | /var/lib/mysql/ | +---------------+-----------------+ 1 row in set (0.00 sec) [root@sqmc system]# vi mysqld.service [root@sqmc system]# service mysqld restart Redirecting to /bin/systemctl restart mysqld.service Warning: The unit file, source configuration file or drop-ins of mysqld.service changed on disk. Run 'systemctl daemon-reload' to reload units. [root@sqmc system]# systemctl daemon-reload [root@sqmc system]# service mysqld restart Redirecting to /bin/systemctl restart mysqld.service Job for mysqld.service failed because the control process exited with error code. See "systemctl status mysqld.service" and "journalctl -xe" for details.

mysqldump備份資料庫檔案

新版mysqldump預設會使用UTF8,不用指定default-character-set 備份資料庫 #mysqldump -h localhost -usqmc sqmctest > sqmctest.sql; [root@Srv ECC-SQMC]# mysql-usqmc -p  > drop database sqmc; > create  database sqmc; > grant .... [root@Srv ECC-SQMC]# mysqldump -usqmc -p sqmc  Enter password: -- MySQL dump 10.13  Distrib 8.0.21, for Linux (x86_64) -- -- Host: localhost    Database: sqmc -- ------------------------------------------------------ -- Server version       8.0.21 /*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */; /*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */; /*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */; /*!50503 SET NAMES utf8mb4 */; /*!40103 SET @OLD_TIME_ZONE=@@TIME_ZONE */; /*!40103 SET TIME_ZONE='+00:00' */; /*!40014 SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */; /*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */; /*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_V