标签：00 service Failed community start mysqld mysql rpm el7
问题描述：启动mysql时报错Failed to start mysqld.service: Unit not found，如下所示：
数据库：mysql 5.7.42
系统：rhel 7.3
1、问题重现
--mysql安装过程
[root@leo-mysql-master ~]# yum localinstall https://dev.mysql.com/get/mysql57-community-release-el7-8.noarch.rpm
[root@leo-mysql-master ~]# yum install -y mysql-community-server
Transaction Summary
==============================================================================================================================================
Install 3 Packages (+2 Dependent packages)
Total download size: 211 M
Downloading packages:
warning: /var/cache/yum/x86_64/7Server/mysql57-community/packages/mysql-community-common-5.7.42-1.el7.x86_64.rpm: Header V4 RSA/SHA256 Signature, key ID 3a79bd29: NOKEY
Public key for mysql-community-common-5.7.42-1.el7.x86_64.rpm is not installed
(1/5): mysql-community-common-5.7.42-1.el7.x86_64.rpm | 311 kB 00:00:00
(2/5): mysql-community-libs-5.7.42-1.el7.x86_64.rpm | 2.6 MB 00:00:01
(3/5): mysql-community-libs-compat-5.7.42-1.el7.x86_64.rpm | 1.2 MB 00:00:00
(4/5): mysql-community-client-5.7.42-1.el7.x86_64.rpm | 28 MB 00:00:05
(5/5): mysql-community-server-5.7.42-1.el7.x86_64.rpm | 179 MB 00:00:25
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Total 7.6 MB/s | 211 MB 00:00:27
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql
Importing GPG key 0x5072E1F5:
Userid : "MySQL Release Engineering <[email protected]>"
Fingerprint: a4a9 4068 76fc bd3c 4567 70c8 8c71 8d3b 5072 e1f5
Package : mysql57-community-release-el7-8.noarch (installed)
From : /etc/pki/rpm-gpg/RPM-GPG-KEY-mysql
Public key for mysql-community-common-5.7.42-1.el7.x86_64.rpm is not installed
Failing package is: mysql-community-common-5.7.42-1.el7.x86_64
GPG Keys are configured as: file:///etc/pki/rpm-gpg/RPM-GPG-KEY-mysql
--此后启动报错如下
[root@leo-mysql-master ~]# systemctl start mysqld.service
Failed to start mysqld.service: Unit not found.
2、异常原因
在使用yum -y install mysql-community-server命令安装mysql时并未安装成功(原因：密钥已安装但不适用此软件包),
安装时报错"Public key for mysql-community-common-5.7.42-1.el7.x86_64.rpm is not installed",
此后使用"systemctl start mysqld.service"命令启动MySQL报"Failed to start mysqld.service: Unit not found."错误
3、解决方案
--在安装mysql之前导入2022年密匙.
[root@leo-mysql-master ~]# rpm --import https://repo.mysql.com/RPM-GPG-KEY-mysql-2022
--重新安装mysql
[root@leo-mysql-master ~]# yum install -y mysql-community-server
--启动mysql进程
[root@leo-mysql-master ~]# systemctl start mysqld.service
[root@leo-mysql-master ~]# systemctl status mysqld.service
● mysqld.service - MySQL Server
Loaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)
Active: active (running) since Sat 2023-07-01 11:02:18 CST; 10s ago
Docs: man:mysqld(8)
http://dev.mysql.com/doc/refman/en/using-systemd.html
Process: 10944 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid $MYSQLD_OPTS (code=exited, status=0/SUCCESS)
Process: 10881 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)
Main PID: 10947 (mysqld)
CGroup: /system.slice/mysqld.service
└─10947 /usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid
Jul 01 11:02:06 leo-mysql-master systemd[1]: Starting MySQL Server...
Jul 01 11:02:18 leo-mysql-master systemd[1]: Started MySQL Server.
说明：如上所示，成功启动mysql进程.
参考文档：https://blog.csdn.net/qq_43788878/article/details/128233209
标签：00,
service,
Failed,
community,
start,
mysqld,
mysql,
rpm,
el7
From： https://blog.51cto.com/u_12991611/6599091