1、备份的时候出现2002报错，找不到/tmp/mysql.sock，这个文件

[root@centos199 backup]# mysqldump -uroot -ppassword cz-office > mysql38.sql
Warning: Using a password on the command line interface can be insecure.
mysqldump: Got error: 2002: Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2) when trying to connect

解决方法：可以先[root@centos199 backup]# ps aux|grep mysql

mysql 20776 0.0 0.7 1824384 56928 ? Sl Feb26 2:29 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/usr/local//mysql/data --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=/var/log/mysqld.log --pid-file=/usr/local//mysql/data/centos199.pid --socket=/var/lib/mysql/mysql.sock ，，

直接做一个软连接就可以解决，[root@centos199 backup]# ln -s /var/lib/mysql/mysql.sock /tmp/mysql.sock

2、备份的时候报这个错是因为mysqldump命令版本的问题，

[root@centos199 backup]# mysqldump -uroot -ppassword cz-office > mysql38.sql

mysqldump: Couldn't execute 'SET OPTION SQL_QUOTE_SHOW_CREATE=1': You have an error in your SQL syntax; check the manual
that corresponds to your MySQL server version for the right syntax to use near 'OPTION SQL_QUOTE_SHOW_CREATE=1' at line 1 (1064)

解决方法：

[root@centos199 ~]# which mysqldump

/usr/bin/mysqldump

[root@centos199 ~]# mysqldump --version

mysqldump Ver 10.13 Distrib 5.1.71, for Linux  (x86_64)

如果你安装的MySQL是5.6以上的版本遇到这种问题，直接将你所安装MySQL目录下的mysqldump这个命令，cp到/usr/bin/下就行

[root@centos199 bin]# pwd
/usr/local/mysql/bin

[root@centos199 bin]# cp mysqldump /usr/bin/mysqldump

[root@centos199 bin]# mysqldump -V
mysqldump Ver 10.13 Distrib 5.6.32, for Linux (x86_64)

3,、备份的时候报错显示密码不安全的问题

[root@centos199 mysql]# mysqldump -uroot -ppassword cz-office > mysql38.sql
Warning: Using a password on the command line interface can be insecure.

解决方法：mysql -u root -ppassword 改成mysql -u root -p 在输入密码即可

如果有不对的地方，欢迎大家指出，谢谢！