最近在做mysqld_multi管理多实例的时候，发现stop不了节点 这是什么原因呢？ 多实例相关配置如下：
[mysqld_multi]
mysqld = /usr/local/mysql/bin/mysqld_safe
mysqladmin = /usr/local/mysql/bin/mysqladmin
log = /usr/local/mysql/mysqld_multi.log
user = root
password = shunzi
[mysqld3306]
socket = /data/mysql3306/tmp/mysql3306.sock
port = 3306
user = mysql
pid-file = /data/mysql3306/mysql3306.pid
datadir = /data/mysql3306/data
tmpdir = /data/mysql3306/tmp
[mysqld3307]
socket = /data/mysql3307/tmp/mysql3307.sock
port = 3307
user = mysql
pid-file = /data/mysql3307/mysql3307.pid
datadir = /data/mysql3307/data
tmpdir = /data/mysql3307/tmp执行mysqld_multi stop 3306时日志报error:
mysqladmin: [Warning] Using a password on the command line interface can be insecure.
mysqladmin: connect to server at 'localhost' failed
error: 'Access denied for user 'root'@'localhost' (using password: YES)'
mysqld_multi log file version 2.16; run: Thu Aug 31 21:09:02 2017这里显示密码错误，手动登录是没有问题的。 这是mysqld_multi的一个bug，详细信息如下 https://bugs.mysql.com/bug.php?id=77227
解决方法是：
修改mysqld_multi文件中的defaults_for_group函数
211 sub defaults_for_group
212 {
213 my ($group) = @_;
214
215 return () unless $my_print_defaults_exists;
216
217 my $com= join ' ', 'my_print_defaults', @defaults_options, $group;
219 my @defaults = $com;
220 chomp @defaults;
221 return @defaults;
222 }
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把 my $com= join ' ', 'my_print_defaults', @defaults_options, $group;
替换为： my $com= join ' ', 'my_print_defaults -s', @defaults_options, $group;在此记录一下！
