解决:
/usr/local/mysql/bin/mysqld_safe --user=mysql & （启动mysql）
killall mysqld -9（重启mysql）
killall mysqld（关闭mysql）
[[email protected] ~]# systemctl stop mysqld
[root@aerchi.com ~]# /usr/local/mysql/bin/mysqld_safe --user=root &
[1] 22090
[root@aerchi.com ~]# 2018-06-25T10:45:52.106908Z mysqld_safe Logging to '/usr/local/mysql/logs/mysqld.log'.
2018-06-25T10:45:52.126600Z mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/data
[root@aerchi.com ~]# killall mysqld -9
[root@aerchi.com ~]# /usr/local/mysql/bin/mysqld_safe: line 198: 22561 Killed nohup /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data --plugin-dir=/usr/local/mysql/lib/plugin --user=root --log-error=/usr/local/mysql/logs/mysqld.log --pid-file=/var/run/mysqld.pid < /dev/null > /dev/null 2>&1
2018-06-25T10:51:44.105560Z mysqld_safe Number of processes running now: 0
2018-06-25T10:51:44.110274Z mysqld_safe mysqld restarted
另:
/usr/local/mysql/bin/mysqld_safe: line 198: 23470 Killed nohup /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data --plugin-dir=/usr/local/mysql/lib/plugin --user=root --log-error=/usr/local/mysql/logs/mysqld.log --pid-file=/var/run/mysqld.pid < /dev/null > /dev/null 2>&1 > /dev/null 2>&1 > /dev/null 2>&1 > /dev/null 2>&1 > /dev/null 2>&1 > /dev/null 2>&1 > /dev/null 2>&1 > /dev/null 2>&1 > /dev/null 2>&1
2018-06-25T11:13:00.053559Z mysqld_safe Number of processes running now: 0
2018-06-25T11:13:00.142445Z mysqld_safe mysqld restarted
解决方法:
vi /etc/security/limits.conf
* soft nproc 65535* hard nproc 65535
* soft nofile 65535
* hard nofile 65535
之后重启服务器。
[root@aerchi.com ~]# mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/data
------------------------------
根据重启mysql 反馈的问题：
第一：查询是否 存在mysql 僵尸进程
#ps -ef |grep mysql*
关闭相关的mysql 僵尸进程。killall mysqld（关闭mysql）
● mysqld.service - LSB: start and stop MySQL
Loaded: loaded (/etc/rc.d/init.d/mysqld; bad; vendor preset: disabled)
Active: active (exited) since Mon 2018-06-25 19:18:36 CST; 17h ago
Docs: man:systemd-sysv-generator(8)
service mysqld restart
MySQL server PID file could not be found! [FAILED]
Starting MySQL.The server quit without updating PID file (/[FAILED]l/mysql/data/i***r6Z.pid).
解决方法:
1. 修改 MySQL的my.cnf 文件
vim /etc/my.cnf
[mysqld]
2 #datadir=/var/lib/mysql
3 #socket=/var/lib/mysql/mysql.sock
4 # Disabling symbolic-links is recommended to prevent assorted security risks
5 #symbolic-links=0
6 # Settings user and group are ignored when systemd is used.
7 # If you need to run mysqld under a different user or group,
8 # customize your systemd unit file for mariadb according to the
9 # instructions in http://fedoraproject.org/wiki/Systemd
10
11 datadir = /usr/local/mysql/data
12
13 [mysqld_safe]
14 log-error=/usr/local/mysql/logs/mysqld.log
15 #pid-file=/var/run/mysqld.pid
16 pid-file=/usr/local/mysql/mysqld.pid
17
18 #
19 # include all files from the config directory
20 #
21 #!includedir /etc/my.cnf.d
22 max_connections = 2000
23 max_user_connections = 1900
24 max_connect_errors = 10000
25 max_allowed_packet = 100M
26 #实际是去除NO_ZERO_IN_DATE,NO_ZER O_DATE
27 disable-partion-engine-check = 1
28 sql_mode = ONLY_FULL_GROUP_BY,STRICT_TRANS_TABLES,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION
29 table_open_cache = 8000
30 connect_timeout = 20
31 wait_timeout=2880000
32 interactive_timeout=2880000
33 # aerchi.com
34 innodb_buffer_pool_size = 128M
35 key_buffer_size = 128M
2. 移除 MySQL配置文件 /etc/my.cnf 注意备份
移除 my.cnf文件，注意备份
备份: mv /etc/my.cnf /etc/my.cnf.backup
重启: service mysqld start
Starting MySQL [ OK ][root@*6Z ~]# 2018-06-29T02:12:15.787884Z mysqld_safe A mysqld process already exists
以上内容，
------------------------------------------------------------------------------------------
当抛错时，应该查看MySQL的日志，
比如错误信息:2018-06-28T04:40:26.338321Z 0 [Note] InnoDB: Using CPU crc32 instructions
2018-06-28T04:40:26.339820Z 0 [Note] InnoDB: Initializing buffer pool, total size = 128M, instances = 1, chunk size = 128M2018-06-28T04:40:26.339855Z 0 [ERROR] InnoDB: mmap(137428992 bytes) failed; errno 12
2018-06-28T04:40:26.340077Z 0 [ERROR] InnoDB: Cannot allocate memory for the buffer pool
请修改my.cnf, 添加
34 innodb_buffer_pool_size = 128M
35 key_buffer_size = 128M
比如错误信息:
Starting MySQL.The server quit without updating PID file (/usr/local/mysql/data/***6Z.pid).
在my.cnf配置文件中的 [mysqld_safe] 下添加
log-error = /apps/logs/mysql/error.log # 表示mysql服务启动日志文件的位置，路径可自己更改
最后发现根源是操作系统未安全关机，MySQL未能安全关闭，而系统表是用myisam引擎的，myisam不支持崩溃修复损坏，然后导致系统表损坏，而启动又检查myisam-recover，无法recover就无法启动了。
提示： MySQL启动时出现:Starting MySQL.The server quit without updating PID file (/usr/local/mysql/data/***6Z.pid).
请注意重启（reboot）即可解决。
# systemctl restart mysqld
Job for mysqld.service failed because the control process exited with error code. See "systemctl status mysqld.service" and "journalctl -xe" for details.
# systemctl status mysqld.service -l
● mysqld.service - LSB: start and stop MySQL
Loaded: loaded (/etc/rc.d/init.d/mysqld; bad; vendor preset: disabled)
Active: failed (Result: exit-code) since Thu 2018-06-28 17:01:27 CST; 1min 19s ago
Docs: man:systemd-sysv-generator(8)
Process: 2576 ExecStart=/etc/rc.d/init.d/mysqld start (code=exited, status=1/FAILURE)
Jun 28 17:01:26 *6Z systemd[1]: Starting LSB: start and stop MySQL...
Jun 28 17:01:27 *6Z mysqld[2576]: Starting MySQL.The server quit without updating PID file (/usr/local/mysql/data/*6Z.pid).[FAILED]
Jun 28 17:01:27 *6Z systemd[1]: mysqld.service: control process exited, code=exited status=1
Jun 28 17:01:27 *6Z systemd[1]: Failed to start LSB: start and stop MySQL.
Jun 28 17:01:27 *6Z systemd[1]: Unit mysqld.service entered failed state.
Jun 28 17:01:27 *6Z systemd[1]: mysqld.service failed.
解决方法:
可能是/usr/local/mysql/data/mysql.pid文件没有写的权限
解决方法 ：给予权限，执行 “chown -R mysql:mysql /var/data” “chmod -R 755 /usr/local/mysql/data” 然后重新启动mysqld！
#/etc/init.d/mysqld status
MySQL is not running, but lock file (/var/lock/subsys/mysql[FAILED]
rm -rf /var/lock/subsys/mysql
-----------------------------------------------------------------
ervice mysqld restart
MySQL server PID file could not be found! [FAILED]
Starting MySQL.2018-06-29T06:52:45.424469Z mysqld_safe error: log-error set to '/usr/local/mysql/logs/mysqld.log', however file don't exists. Create writable for user 'mysql'.
The server quit without updating PID file (/usr/local/mysql/data/iZwz99mho1vp798njmvvr6Z.pid). [FAILED]
[root@*6Z ~]# touch /usr/local/mysql/logs/mysqld.log
[root@*6Z ~]# chown -R mysql:mysql /usr/local/mysql/logs/
------------
[root@*6Z ~]#touch /usr/local/mysql/data/mysqld.pid
[root@*6Z ~]# touch /usr/local/mysql/data/mysqld.pid
[root@*6Z ~]# service mysqld restart
--------------------------------------------------------------------------------
service mysqld start
Starting MySQL [ OK ]
# 2018-06-29T15:12:57.189830Z mysqld_safe A mysqld process already exists
ps -ef|grep mysql
kill -9 mysql进程
service mysqld start
Starting MySQL [ OK ]
当出现 MySQL server PID file could not be found! , 请尝试做好my.cnf 备份并删除。
cp /etc/my.cnf~ /etc/my.cnf
rm -rf /etc/my.cnf
--------------------------------------------------------------------------------
重新启动 systemctl restart mysqld / service mysqld start
查看进程 ps -ef |grep mysqlroot 6343 1 0 14:00 pts/1 00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --datadir=/usr/local/mysql/data --pid-file=/usr/local/mysql/data/***6Z.pid
mysql 6600 6343 1 14:00 pts/1 00:00:10 /usr/local/mysql/bin/mysqld .....data/***6Z.pid
root 7559 5728 0 14:13 pts/1 00:00:00 grep --color=auto mysql
再次查看日志正常了
乐意黎
2018-06-28