我在Mac OS X v10.7.5 (Lion)上尝试升级时遇到了这个问题。

不幸的是，MySQL也从5.5.14升级到5.6.10。我尝试了新版本，但它不起作用。

我决定回到我以前的设置，做了一个

brew switch mysql 5.5.14

这并没有解决问题。我在其他地方阅读并这样做了，瞧!一切都回来了:)

cd /usr/local/var/mysql
mv ib_logfile0 ib_logfile0.bak
mv ib_logfile1 ib_logfile1.bak

对我来说，解决方案是覆盖/纠正/etc/my/cnf中的数据目录

我用自述文件中提供的说明从源代码构建MySQL 5.5.27:

# Preconfiguration setup
shell> groupadd mysql
shell> useradd -r -g mysql mysql
# Beginning of source-build specific instructions
shell> tar zxvf mysql-VERSION.tar.gz
shell> cd mysql-VERSION
shell> cmake .
shell> make
shell> make install
# End of source-build specific instructions

# Postinstallation setup
shell> cd /usr/local/mysql
shell> chown -R mysql .
shell> chgrp -R mysql .
shell> scripts/mysql_install_db --user=mysql
shell> chown -R root .
shell> chown -R mysql data

# Next command is optional
shell> cp support-files/my-medium.cnf /etc/my.cnf
shell> bin/mysqld_safe --user=mysql &

# Next command is optional
shell> cp support-files/mysql.server /etc/init.d/mysql.server

Mysqld_safe在没有解释的情况下自行终止。运行/etc/init.d/mysql.服务器启动导致错误:

服务器退出没有更新PID文件

I noticed something odd in the installation instructions though. It has ownership changed to mysql for the directory "data", but not to "var"; this is unusual because for years I have had to ensure that var directory was mysql writable. So I manually ran chown -R mysql /usr/local/mysql/var and then attempted to start it again. Still no luck. But worse, no .err file in the var dir - it was in the "data" dir! so scripts/mysql_install_db sets up camp in /usr/local/mysql/var, but the rest of the application seems to want to do its work in /usr/local/mysql/data!

所以我只是编辑了/etc/my.cnf，在部分[mysqld]下，我添加了一个指令，显式地将mysql的数据目录指向var(因为我通常期望它是任何方式)，这样做之后，mysqld启动得很好。add指令看起来像这样:

数据= /usr/地方/mysql/var

为我工作。希望对你有所帮助。

我的错误文件还告诉我，端口可能正在被另一个进程使用，但只是运行sudo mysql。服务器启动修复了我的问题。

当MySQL被不正确地关闭后试图启动MySQL时，可能会发生此错误。

Take a look at the MySQL error log file. If it mentions something like "Check that you do not already have another mysqld process using the same data or log files.", then you need to properly shutdown that process. See what process MySQL is running on. Use the command lsof -i:3306 (the default port number for MySQL is 3306). Your output should look like this: COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME mysqld 4249 username 17u IPv4 0x7843d9d130469c0b 0t0 TCP localhost:mysql (LISTEN) Terminate the process running mysql: kill -15 4249 Kill -15 sends a signal to the process to free up any resources it is locking and terminate the process after. Now MySQL should start up with no problems: mysql.server start

如果您正在运行MySQL Galera集群，例如Percona XtraDB集群，请检查wsrep_recovery。*数据目录下的文件(例如:/var/lib/mysql)。

当我试图启动一个已经被主机的OOM杀手杀死的节点时，我从systemctl得到了相同的消息，但在任何正常日志中都没有任何迹象表明为什么启动失败。wsprep恢复文件有答案，在我的情况下，我需要用以下标志启动MySQL:

mysqld --tc-heuristic-recover=ROLLBACK

尝试删除ib_logfile0和ib_logfile1文件，然后再次运行MySQL:

rm /usr/local/var/mysql/ib_logfile0
rm /usr/local/var/mysql/ib_logfile1

这对我很管用。