我在 ubuntu 18.04 上卸载并重新安装了 mysql，然后尝试了以下操作：
$ sudo service mysql start
~$ sudo /etc/init.d/mysql start
[ ok ] Starting mysql (via systemctl): mysql.service.
~$ sudo systemctl start mysqld
Failed to start mysqld.service: Unit mysqld.service not found.
我使用以下命令删除 mysql，其结果也如下所示：
$ sudo apt-get remove --purge mysql-\*
Reading package lists... Done
Building dependency tree
Reading state information... Done
Note, selecting 'mysql-workbench' for glob 'mysql-*'
Note, selecting 'mysql-client-5.5' for glob 'mysql-*'
Note, selecting 'mysql-client-5.6' for glob 'mysql-*'
Note, selecting 'mysql-client-5.7' for glob 'mysql-*'
Note, selecting 'mysql-common-5.6' for glob 'mysql-*'
Note, selecting 'mysql-server-5.0' for glob 'mysql-*'
Note, selecting 'mysql-server-5.1' for glob 'mysql-*'
Note, selecting 'mysql-server-5.5' for glob 'mysql-*'
Note, selecting 'mysql-server-5.6' for glob 'mysql-*'
Note, selecting 'mysql-server-5.7' for glob 'mysql-*'
Note, selecting 'mysql-utilities' for glob 'mysql-*'
Note, selecting 'mysql-testsuite' for glob 'mysql-*'
Note, selecting 'mysql-server' for glob 'mysql-*'
Note, selecting 'mysql-client' for glob 'mysql-*'
Note, selecting 'mysql-sandbox' for glob 'mysql-*'
Note, selecting 'mysql-client-core-5.5' for glob 'mysql-*'
Note, selecting 'mysql-client-core-5.6' for glob 'mysql-*'
Note, selecting 'mysql-client-core-5.7' for glob 'mysql-*'
Note, selecting 'mysql-testsuite-5.5' for glob 'mysql-*'
Note, selecting 'mysql-testsuite-5.6' for glob 'mysql-*'
Note, selecting 'mysql-testsuite-5.7' for glob 'mysql-*'
Note, selecting 'mysql-common' for glob 'mysql-*'
Note, selecting 'mysql-workbench-data' for glob 'mysql-*'
Note, selecting 'mysql-server-core-5.1' for glob 'mysql-*'
Note, selecting 'mysql-server-core-5.5' for glob 'mysql-*'
Note, selecting 'mysql-server-core-5.6' for glob 'mysql-*'
Note, selecting 'mysql-server-core-5.7' for glob 'mysql-*'
Note, selecting 'mysql-source-5.7' for glob 'mysql-*'
Package 'mysql-client-5.5' is not installed, so not removed
Package 'mysql-client-5.6' is not installed, so not removed
Package 'mysql-server-core-5.6' is not installed, so not removed
Package 'mysql-client-core-5.5' is not installed, so not removed
Package 'mysql-client-core-5.6' is not installed, so not removed
Note, selecting 'mysql-common' instead of 'mysql-common-5.6'
Package 'mysql-server-5.5' is not installed, so not removed
Package 'mysql-server-5.6' is not installed, so not removed
Package 'mysql-server-core-5.5' is not installed, so not removed
Package 'mysql-testsuite-5.5' is not installed, so not removed
Package 'mysql-testsuite-5.6' is not installed, so not removed
Package 'mysql-server-5.0' is not installed, so not removed
Package 'mysql-server-5.1' is not installed, so not removed
Package 'mysql-server-core-5.1' is not installed, so not removed
Package 'mysql-sandbox' is not installed, so not removed
Package 'mysql-source-5.7' is not installed, so not removed
Package 'mysql-testsuite' is not installed, so not removed
Package 'mysql-testsuite-5.7' is not installed, so not removed
The following packages were automatically installed and are no longer required:
gdal-data libaec0 libarmadillo8 libarpack2 libatkmm-1.6-1v5 libblas3
libcairomm-1.0-1v5 libcoin80v5 libctemplate3 libdap25 libdapclient6v5
libepsilon1 libevent-core-2.1-6 libfreexl1 libfyba0 libgeos-3.6.2
libgeos-c1v5 libgeos-dev libgeotiff2 libglibmm-2.4-1v5
libgnome-keyring-common libgnome-keyring0 libgraphicsmagick-q16-3
libgtkmm-2.4-1v5 libhdf4-0-alt libhdf5-100 libiso9660-10 libkmlbase1
libkmldom1 libkmlengine1 liblapack3 libmad0 libmng2 libnetcdf13 libodbc1
libogdi3.2 libopenthreads-dev libopenthreads20 libpangomm-1.4-1v5 libpq5
libproj12 libqhull7 libspatialite7 libsuperlu5 libsz2 libtinyxml2.6.2v5
liburiparser1 libvcdinfo0 libvsqlitepp3v5 libxerces-c3.2 libxine2
libxine2-bin libxine2-doc libxine2-ffmpeg libxine2-misc-plugins
libxine2-plugins odbcinst odbcinst1debian2 proj-bin proj-data
python-mysql.connector python-paramiko python-pexpect python-ptyprocess
python-pyodbc python-pysqlite2
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
dbconfig-no-thanks
The following packages will be REMOVED:
dbconfig-mysql* libgdal20* libmysqlclient20* libmysqlcppconn7v5*
libopenscenegraph-3.4-131* libopenscenegraph-3.4-dev* libosgearth-dev*
libosgearth5* libosgearthannotation5* libosgearthfeatures5*
libosgearthqt5-5* libosgearthsplat5* libosgearthsymbology5*
libosgearthutil5* mysql-client* mysql-client-5.7* mysql-client-core-5.7*
mysql-common* mysql-server* mysql-server-5.7* mysql-server-core-5.7*
mysql-utilities* mysql-workbench* mysql-workbench-data*
openscenegraph-plugin-osgearth*
The following NEW packages will be installed:
dbconfig-no-thanks
0 upgraded, 1 newly installed, 25 to remove and 12 not upgraded.
2 not fully installed or removed.
Need to get 1,314 B of archives.
After this operation, 337 MB disk space will be freed.
Do you want to continue? [Y/n] Y
Get:1 http://us.archive.ubuntu.com/ubuntu bionic/universe amd64 dbconfig-no-thanks all 2.0.9 [1,314 B]
Fetched 1,314 B in 0s (3,420 B/s)
dpkg: warning: files list file for package 'mysql-common' missing; assuming package has no files currently installed
(Reading database ... 230311 files and directories currently installed.)
Removing mysql-server (5.7.37-0ubuntu0.18.04.1) ...
Removing mysql-server-5.7 (5.7.37-0ubuntu0.18.04.1) ...
dpkg: dbconfig-mysql: dependency problems, but removing anyway as you requested:
phpmyadmin depends on dbconfig-mysql | dbconfig-no-thanks | dbconfig-common (<< 2.0.0); however:
Package dbconfig-mysql is to be removed.
Package dbconfig-no-thanks is not installed.
Version of dbconfig-common on system is 2.0.9.
Removing dbconfig-mysql (2.0.9) ...
Selecting previously unselected package dbconfig-no-thanks.
dpkg: warning: files list file for package 'mysql-common' missing; assuming package has no files currently installed
(Reading database ... 230233 files and directories currently installed.)
Preparing to unpack .../dbconfig-no-thanks_2.0.9_all.deb ...
Unpacking dbconfig-no-thanks (2.0.9) ...
dpkg: warning: files list file for package 'mysql-common' missing; assuming package has no files currently installed
(Reading database ... 230234 files and directories currently installed.)
Removing openscenegraph-plugin-osgearth (2.9.0+dfsg-1) ...
Removing mysql-workbench (6.3.8+dfsg-1build3) ...
Removing libosgearth-dev (2.9.0+dfsg-1) ...
Removing libmysqlcppconn7v5:amd64 (1.1.9-1) ...
Removing libopenscenegraph-3.4-dev (3.4.1+dfsg1-3) ...
Removing libosgearthsplat5 (2.9.0+dfsg-1) ...
Removing libosgearthqt5-5 (2.9.0+dfsg-1) ...
Removing mysql-client (5.7.37-0ubuntu0.18.04.1) ...
Removing mysql-client-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Removing mysql-client-core-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Removing mysql-server-core-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Removing mysql-utilities (1.6.4-1) ...
Removing mysql-workbench-data (6.3.8+dfsg-1build3) ...
Removing libosgearthutil5 (2.9.0+dfsg-1) ...
Removing libosgearthannotation5 (2.9.0+dfsg-1) ...
Removing libosgearthfeatures5 (2.9.0+dfsg-1) ...
Removing libosgearthsymbology5 (2.9.0+dfsg-1) ...
Removing libosgearth5 (2.9.0+dfsg-1) ...
Removing libopenscenegraph-3.4-131:amd64 (3.4.1+dfsg1-3) ...
Removing libgdal20 (2.2.3+dfsg-2) ...
Removing libmysqlclient20:amd64 (5.7.37-0ubuntu0.18.04.1) ...
Removing mysql-common (5.8+1.0.4) ...
Setting up dbconfig-no-thanks (2.0.9) ...
Processing triggers for desktop-file-utils (0.23-1ubuntu3.18.04.2) ...
Processing triggers for libc-bin (2.27-3ubuntu1.4) ...
Processing triggers for man-db (2.8.3-2ubuntu0.1) ...
Processing triggers for shared-mime-info (1.9-2) ...
Processing triggers for gnome-menus (3.13.3-11ubuntu1.1) ...
Processing triggers for hicolor-icon-theme (0.17-2) ...
Processing triggers for mime-support (3.60ubuntu1) ...
(Reading database ... 227342 files and directories currently installed.)
Purging configuration files for mysql-common (5.8+1.0.4) ...
Purging configuration files for mysql-utilities (1.6.4-1) ...
Purging configuration files for mysql-server-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Processing triggers for systemd (237-3ubuntu10.53) ...
Processing triggers for ureadahead (0.100.0-21) ...
ureadahead will be reprofiled on next reboot
然后我尝试使用以下命令重新安装，但出现了 stat 文件错误：
:~$ sudo apt-get install mysql-server mysql-client
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
gdal-data libaec0 libarmadillo8 libarpack2 libatkmm-1.6-1v5 libblas3
libcairomm-1.0-1v5 libcoin80v5 libctemplate3 libdap25 libdapclient6v5
libepsilon1 libfreexl1 libfyba0 libgeos-3.6.2 libgeos-c1v5 libgeos-dev
libgeotiff2 libglibmm-2.4-1v5 libgnome-keyring-common libgnome-keyring0
libgraphicsmagick-q16-3 libgtkmm-2.4-1v5 libhdf4-0-alt libhdf5-100
libiso9660-10 libkmlbase1 libkmldom1 libkmlengine1 liblapack3 libmad0
libmng2 libnetcdf13 libodbc1 libogdi3.2 libopenthreads-dev libopenthreads20
libpangomm-1.4-1v5 libpq5 libproj12 libqhull7 libspatialite7 libsuperlu5
libsz2 libtinyxml2.6.2v5 liburiparser1 libvcdinfo0 libvsqlitepp3v5
libxerces-c3.2 libxine2 libxine2-bin libxine2-doc libxine2-ffmpeg
libxine2-misc-plugins libxine2-plugins odbcinst odbcinst1debian2 proj-bin
proj-data python-mysql.connector python-paramiko python-pexpect
python-ptyprocess python-pyodbc python-pysqlite2
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
mysql-client-5.7 mysql-client-core-5.7 mysql-common mysql-server-5.7
mysql-server-core-5.7
Suggested packages:
mailx tinyca
The following NEW packages will be installed:
mysql-client mysql-client-5.7 mysql-client-core-5.7 mysql-common
mysql-server mysql-server-5.7 mysql-server-core-5.7
0 upgraded, 7 newly installed, 0 to remove and 12 not upgraded.
Need to get 7,308 B/18.9 MB of archives.
After this operation, 154 MB of additional disk space will be used.
Do you want to continue? [Y/n] Y
Get:1 http://us.archive.ubuntu.com/ubuntu bionic/main amd64 mysql-common all 5.8+1.0.4 [7,308 B]
Fetched 7,308 B in 0s (23.3 kB/s)
Preconfiguring packages ...
Selecting previously unselected package mysql-common.
(Reading database ... 227329 files and directories currently installed.)
Preparing to unpack .../mysql-common_5.8+1.0.4_all.deb ...
Unpacking mysql-common (5.8+1.0.4) ...
Selecting previously unselected package mysql-client-core-5.7.
Preparing to unpack .../mysql-client-core-5.7_5.7.37-0ubuntu0.18.04.1_amd64.deb ...
Unpacking mysql-client-core-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Selecting previously unselected package mysql-client-5.7.
Preparing to unpack .../mysql-client-5.7_5.7.37-0ubuntu0.18.04.1_amd64.deb ...
Unpacking mysql-client-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Selecting previously unselected package mysql-server-core-5.7.
Preparing to unpack .../mysql-server-core-5.7_5.7.37-0ubuntu0.18.04.1_amd64.deb ...
Unpacking mysql-server-core-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Setting up mysql-common (5.8+1.0.4) ...
update-alternatives: warning: alternative /etc/mysql/mysql.cnf (part of link group my.cnf) doesn't exist; removing from list of alternatives
update-alternatives: warning: /etc/alternatives/my.cnf is dangling; it will be updated with best choice
update-alternatives: using /etc/mysql/my.cnf.fallback to provide /etc/mysql/my.cnf (my.cnf) in auto mode
Selecting previously unselected package mysql-server-5.7.
(Reading database ... 227485 files and directories currently installed.)
Preparing to unpack .../mysql-server-5.7_5.7.37-0ubuntu0.18.04.1_amd64.deb ...
Unpacking mysql-server-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Selecting previously unselected package mysql-client.
Preparing to unpack .../mysql-client_5.7.37-0ubuntu0.18.04.1_all.deb ...
Unpacking mysql-client (5.7.37-0ubuntu0.18.04.1) ...
Selecting previously unselected package mysql-server.
Preparing to unpack .../mysql-server_5.7.37-0ubuntu0.18.04.1_all.deb ...
Unpacking mysql-server (5.7.37-0ubuntu0.18.04.1) ...
Setting up mysql-server-core-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Setting up mysql-client-core-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Setting up mysql-client-5.7 (5.7.37-0ubuntu0.18.04.1) ...
Setting up mysql-client (5.7.37-0ubuntu0.18.04.1) ...
Setting up mysql-server-5.7 (5.7.37-0ubuntu0.18.04.1) ...
update-alternatives: using /etc/mysql/mysql.cnf to provide /etc/mysql/my.cnf (my.cnf) in auto mode
Renaming removed key_buffer and myisam-recover options (if present)
Cannot stat file /proc/10333/fd/4: Permission denied
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Cannot stat file /proc/10333/fd/16: Permission denied
Cannot stat file /proc/10333/fd/17: Permission denied
Cannot stat file /proc/10333/fd/48: Permission denied
Cannot stat file /proc/10333/fd/72: Permission denied
Cannot stat file /proc/10333/fd/87: Permission denied
Cannot stat file /proc/10333/fd/90: Permission denied
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Cannot stat file /proc/10377/fd/103: Permission denied
Cannot stat file /proc/10423/fd/4: Permission denied
Cannot stat file /proc/10423/fd/5: Permission denied
Cannot stat file /proc/10423/fd/11: Permission denied
Cannot stat file /proc/10423/fd/14: Permission denied
Cannot stat file /proc/10423/fd/15: Permission denied
Cannot stat file /proc/10423/fd/16: Permission denied
Cannot stat file /proc/10423/fd/17: Permission denied
Cannot stat file /proc/10423/fd/24: Permission denied
Cannot stat file /proc/10423/fd/48: Permission denied
Cannot stat file /proc/10423/fd/72: Permission denied
Cannot stat file /proc/10423/fd/87: Permission denied
Cannot stat file /proc/10423/fd/90: Permission denied
Cannot stat file /proc/10423/fd/93: Permission denied
Cannot stat file /proc/10423/fd/96: Permission denied
Cannot stat file /proc/10423/fd/1023: Permission denied
Cannot stat file /proc/10424/fd/4: Permission denied
Cannot stat file /proc/10424/fd/5: Permission denied
Cannot stat file /proc/10424/fd/11: Permission denied
Cannot stat file /proc/10424/fd/14: Permission denied
Cannot stat file /proc/10424/fd/15: Permission denied
Cannot stat file /proc/10424/fd/16: Permission denied
Cannot stat file /proc/10424/fd/17: Permission denied
Cannot stat file /proc/10424/fd/24: Permission denied
Cannot stat file /proc/10424/fd/48: Permission denied
Cannot stat file /proc/10424/fd/72: Permission denied
Cannot stat file /proc/10424/fd/87: Permission denied
Cannot stat file /proc/10424/fd/90: Permission denied
Cannot stat file /proc/10424/fd/93: Permission denied
Cannot stat file /proc/10424/fd/96: Permission denied
Cannot stat file /proc/10424/fd/1023: Permission denied
AppArmor parser error for /etc/apparmor.d/usr.sbin.mysqld in /etc/apparmor.d/usr.sbin.mysqld at line 9: Could not open 'abstractions/mysql'
Setting up mysql-server (5.7.37-0ubuntu0.18.04.1) ...
Processing triggers for systemd (237-3ubuntu10.53) ...
Processing triggers for man-db (2.8.3-2ubuntu0.1) ...
Processing triggers for ureadahead (0.100.0-21) …
请有人指导我如何解决 mysqld 问题。
祖尔菲。
答案1
按照此处的说明进行操作：https://stackoverflow.com/questions/62127891/cant-install-mysql-on-pure-ubuntu-20-04
sudo apt-get purge mysql*
sudo apt-get autoremove
sudo apt-get autoclean
sudo apt-get remove dbconfig-mysql
sudo apt-get dist-upgrade
//This successfully removed it and I was able to install:
sudo apt update
sudo apt install mysql-server
sudo apt install mysql-client
sudo mysql_secure_installation
但是，它无法启动，给出 Can't connect to local MySQL server through socket error。同样的问题有一个解决方案：
sudo mysqld_safe --skip-grant-tables --skip-syslog --skip-networking
然后在新的终端中运行mysql：
mysql -u root
如果出现访问被拒绝错误，请在 mysql 之前使用 sudo：
sudo mysql -u root
如果您已给出任何 root 密码，请使用-p标志命令来提示输入密码：
sudo mysql -u root -p