我试图在ubuntu 16上安装apache和mysql服务器。

Question

请有人告诉我为什么我的航站楼显示：

root@prince-HP-ProBook-6470b:~# 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:
  galera-3 iproute libdbd-mysql-perl libdbi-perl libjemalloc1
  libmariadbclient18 libmysqlclient18 libreadline5 mariadb-common socat
Use 'sudo apt autoremove' to remove them.
The following additional packages will be installed:
  mysql-server-5.7
Suggested packages:
  mailx tinyca
The following NEW packages will be installed:
  mysql-client mysql-server mysql-server-5.7
0 upgraded, 3 newly installed, 0 to remove and 4 not upgraded.
Need to get 0 B/2,592 kB of archives.
After this operation, 48.6 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Preconfiguring packages ...
(Reading database ... 189575 files and directories currently installed.)
Preparing to unpack .../mysql-server-5.7_5.7.15-0ubuntu0.16.04.1_amd64.deb ...
Aborting downgrade from (at least) 10.1 to 5.7.
If are sure you want to downgrade to 5.7, remove the file
/var/lib/mysql/debian-*.flag and try installing again.
dpkg: error processing archive /var/cache/apt/archives/mysql-server-5.7_5.7.15-0ubuntu0.16.04.1_amd64.deb (--unpack):
 subprocess new pre-installation script returned error exit status 1
Selecting previously unselected package mysql-client.
Preparing to unpack .../mysql-client_5.7.15-0ubuntu0.16.04.1_all.deb ...
Unpacking mysql-client (5.7.15-0ubuntu0.16.04.1) ...
Selecting previously unselected package mysql-server.
Preparing to unpack .../mysql-server_5.7.15-0ubuntu0.16.04.1_all.deb ...
Unpacking mysql-server (5.7.15-0ubuntu0.16.04.1) ...
Errors were encountered while processing:
 /var/cache/apt/archives/mysql-server-5.7_5.7.15-0ubuntu0.16.04.1_amd64.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
root@prince-HP-ProBook-6470b:~# systemctl start apache2
root@prince-HP-ProBook-6470b:~# apt-get purge apache2
Reading package lists... Done
Building dependency tree       
Reading state information... Done
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
 mysql-server : Depends: mysql-server-5.7 but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

Answer 1

 sudo apt-get autoclean

删除sources.list file.and创建新sources.list..。

sudo rm /etc/apt/sources.list 

然后，输入

sudo software-properties-gtk 

这将打开软件属性-gtk和newsources.list will自动创建。

然后将服务器更改为US或您选择的任何其他服务器。您必须从新对话框中启用存储库，以便创建新的sources.list。

勾选所有框，然后单击“还原”，然后单击“关闭”。

需要还原默认存储库

 sudo apt-get update && sudo apt-get dist-upgrade -y

(在安装之前备份此文件是很好的做法，以便在发生这种情况时恢复)

现在安装任何东西！

Answer 2

这个op显示，在此之前您已经安装了mariadb，现在您正在安装mysql服务器，这似乎导致了这个问题。最好删除mariadb、mysql-server和apache，并清理缓存，并尝试重新安装mysql-server和apache。

移除马里亚布。

sudo apt-get remove --purge mariadb-*

如果安装，请删除mysql服务器和apache2。

sudo apt-get remove --purge mysql-server apache2

删除不需要的依赖项并进行清理。

 sudo apt-get autoremove
 sudo apt-get autoclean

现在开始一个接一个地安装。

注意:不要安装mariadb和mysql-server，这两者都是因为fromer是后者的分叉，两者都能满足相同的目的。