问题
[root@centos74 ~]# service mysqld start
Starting MySQL.. ERROR! The server quit without updating PID file (/usr/local/mysql/data/mysqld.pid).
分析解决
1、 可能已经存在 mysqld 进程.
[root@centos74 ~]# ps -ef | grep mysqld
[root@centos74 ~]# pkill -9 mysqld
# 查看是否有这个进程，如果有杀死掉
2、数据目录mysql用户是否有权限.
[root@centos74 ~]# chown -R mysql.mysql /usr/local/mysql/data
3、机器上面还有上次安装mysql的残留.
[root@centos74 ~]# find / -name mysql-binlog*
# 查看mysql的二进制目录，看是否存在mysqlbinlog.index,有的话删掉
4、mysql 在启动的时候会去寻找默认的 配置文件 /etc/my.cnf 这个目录下的 datadir 要指定数据目录.
# 如果没有，那么在 my.cnf 里面添加 datadir=/usr/local/mysql/data
5、skip-federated字段问题.
# 检查一下/etc/my.cnf文件中有没有没被注释掉的skip-federated字段，如果有就立即注释掉.
6、错误日志目录不存在.
# 赋予 mysql 所有者权限 chmod chown .
7、防火墙原因.
# centos 会默认开启selinux .
[root@centos74 ~]# vim /etc/selinux/config
SELINUX=disabled
8、查看配置文件/usr/local/mysql/my.cnf里有没有innodb_buffer_pool_size
# innodb_buffer_pool_size：主要作用是缓存innodb表的索引，数据，插入数据时的缓冲.
# 默认值：128M；
# 专用mysql服务器设置此值的大小： 系统内存的70%-80%最佳.
# 如果你的系统内存不大，查看这个参数，把它的值设置小一点.
10、关注 mysql 的报错日志.
[root@centos74 /]# cd /usr/local/mysql/
[root@centos74 mysql]# cat mysql.err
190718 8:31:56 [Note] Plugin 'FEDERATED' is disabled.
mysqld: Table 'mysql.plugin' doesn't exist
190718 8:31:56 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
190718 8:31:56 InnoDB: The InnoDB memory heap is disabled
190718 8:31:56 InnoDB: Mutexes and rw_locks use GCC atomic builtins
190718 8:31:56 InnoDB: Compressed tables use zlib 1.2.11
190718 8:31:56 InnoDB: Using Linux native AIO
190718 8:31:56 InnoDB: Initializing buffer pool, size = 128.0M
190718 8:31:56 InnoDB: Completed initialization of buffer pool
InnoDB: The first specified data file ./ibdata1 did not exist:
InnoDB: a new database to be created!
190718 8:31:56 InnoDB: Setting file ./ibdata1 size to 10 MB
InnoDB: Database physically writes the file full: wait...
190718 8:31:56 InnoDB: Log file ./ib_logfile0 did not exist: new to be created
InnoDB: Setting log file ./ib_logfile0 size to 5 MB
InnoDB: Database physically writes the file full: wait...
190718 8:31:56 InnoDB: Log file ./ib_logfile1 did not exist: new to be created
InnoDB: Setting log file ./ib_logfile1 size to 5 MB
InnoDB: Database physically writes the file full: wait...
InnoDB: Doublewrite buffer not found: creating new
InnoDB: Doublewrite buffer created
InnoDB: 127 rollback segment(s) active.
InnoDB: Creating foreign key constraint system tables
InnoDB: Foreign key constraint system tables created
190718 8:31:56 InnoDB: Waiting for the background threads to start
190718 8:31:57 InnoDB: 5.5.62 started; log sequence number 0
190718 8:31:57 [ERROR] mysqld: unknown option '--initialize'
190718 8:31:57 [ERROR] Aborting
190718 8:31:57 InnoDB: Starting shutdown...
190718 8:31:58 InnoDB: Shutdown completed; log sequence number 1595675
190718 8:31:58 [Note] mysqld: Shutdown complete
190718 8:32:07 [Note] Plugin 'FEDERATED' is disabled.
/usr/local/mysql/bin/mysqld: Table 'mysql.plugin' doesn't exist
190718 8:32:07 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
190718 8:32:07 InnoDB: The InnoDB memory heap is disabled
190718 8:32:07 InnoDB: Mutexes and rw_locks use GCC atomic builtins
190718 8:32:07 InnoDB: Compressed tables use zlib 1.2.11
190718 8:32:07 InnoDB: Using Linux native AIO
190718 8:32:07 InnoDB: Initializing buffer pool, size = 128.0M
190718 8:32:07 InnoDB: Completed initialization of buffer pool
190718 8:32:07 InnoDB: highest supported file format is Barracuda.
190718 8:32:07 InnoDB: Waiting for the background threads to start
190718 8:32:08 InnoDB: 5.5.62 started; log sequence number 1595675
190718 8:32:08 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
190718 8:32:08 [Note] - '0.0.0.0' resolves to '0.0.0.0';
190718 8:32:08 [Note] Server socket created on IP: '0.0.0.0'.
190718 8:32:08 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
190718 8:33:17 [Note] Plugin 'FEDERATED' is disabled.
/usr/local/mysql/bin/mysqld: Table 'mysql.plugin' doesn't exist
190718 8:33:17 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
190718 8:33:17 InnoDB: The InnoDB memory heap is disabled
190718 8:33:17 InnoDB: Mutexes and rw_locks use GCC atomic builtins
190718 8:33:17 InnoDB: Compressed tables use zlib 1.2.11
190718 8:33:17 InnoDB: Using Linux native AIO
190718 8:33:17 InnoDB: Initializing buffer pool, size = 128.0M
190718 8:33:17 InnoDB: Completed initialization of buffer pool
190718 8:33:17 InnoDB: highest supported file format is Barracuda.
190718 8:33:17 InnoDB: Waiting for the background threads to start
190718 8:33:18 InnoDB: 5.5.62 started; log sequence number 1595675
190718 8:33:18 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
190718 8:33:18 [Note] - '0.0.0.0' resolves to '0.0.0.0';
190718 8:33:18 [Note] Server socket created on IP: '0.0.0.0'.
190718 8:33:18 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
190718 8:36:58 [Note] Plugin 'FEDERATED' is disabled.
/usr/local/mysql/bin/mysqld: Table 'mysql.plugin' doesn't exist
190718 8:36:58 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
190718 8:36:58 InnoDB: The InnoDB memory heap is disabled
190718 8:36:58 InnoDB: Mutexes and rw_locks use GCC atomic builtins
190718 8:36:58 InnoDB: Compressed tables use zlib 1.2.11
190718 8:36:58 InnoDB: Using Linux native AIO
190718 8:36:58 InnoDB: Initializing buffer pool, size = 128.0M
190718 8:36:58 InnoDB: Completed initialization of buffer pool
190718 8:36:58 InnoDB: highest supported file format is Barracuda.
190718 8:36:58 InnoDB: Waiting for the background threads to start
190718 8:36:59 InnoDB: 5.5.62 started; log sequence number 1595675
190718 8:36:59 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
190718 8:36:59 [Note] - '0.0.0.0' resolves to '0.0.0.0';
190718 8:36:59 [Note] Server socket created on IP: '0.0.0.0'.
190718 8:36:59 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist
