Mysql将不会在移动数据后启动，丢失sock文件

Question

在Ubuntu16.04的新安装和mysql的新安装中，我以类似于这 post的方式移动mysql数据，但是在它之后，当我尝试重新启动/启动mysql时，我得到：

error: can't connect to local MySQL server throught socket '/var/run/mysqld/mysql.sock' (2) 
Check that mysqld is running and that the socket: '/var/run/mysqld/mysql.sock' exists!

文件夹/var/run/mysqld存在，但不存在该文件。

当我运行：find / -type s时，文件mysql.sock不在列表中。

journalctl -xe的结果：

-- Unit mysql.service has finished shutting down.
Jun 12 11:45:16 wkssop-hev7 systemd[1]: Starting MySQL Community Server...
-- Subject: Unit mysql.service has begun start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel

-- Unit mysql.service has begun starting up.
Jun 12 11:45:16 wkssop-hev7 audit[5882]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/5882/status" pid=5882 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=110 ouid=110
Jun 12 11:45:16 wkssop-hev7 audit[5882]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=5882 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=110 ouid=0
Jun 12 11:45:16 wkssop-hev7 audit[5882]: AVC apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/5882/status" pid=5882 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=110 ouid=110
Jun 12 11:45:16 wkssop-hev7 kernel: audit: type=1400 audit(1497260716.044:133): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/5882/status" pid=5882 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=110 ouid=110
Jun 12 11:45:16 wkssop-hev7 kernel: audit: type=1400 audit(1497260716.044:134): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/sys/devices/system/node/" pid=5882 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=110 ouid=0
Jun 12 11:45:16 wkssop-hev7 kernel: audit: type=1400 audit(1497260716.044:135): apparmor="DENIED" operation="open" profile="/usr/sbin/mysqld" name="/proc/5882/status" pid=5882 comm="mysqld" requested_mask="r" denied_mask="r" fsuid=110 ouid=110
Jun 12 11:45:17 wkssop-hev7 systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE

systemctl status mysql.service的结果是：

● mysql.service - MySQL Community Server
   Loaded: loaded (/lib/systemd/system/mysql.service; enabled; vendor preset: enabled)
   Active: activating (start-post) (Result: exit-code) since Mon 2017-06-12 11:45:46 CEST; 6s ago
  Process: 5986 ExecStart=/usr/sbin/mysqld (code=exited, status=1/FAILURE)
  Process: 5978 ExecStartPre=/usr/share/mysql/mysql-systemd-start pre (code=exited, status=0/SUCCESS)
 Main PID: 5986 (code=exited, status=1/FAILURE);         : 5987 (mysql-systemd-s)
    Tasks: 2
   Memory: 1.4M
      CPU: 259ms
   CGroup: /system.slice/mysql.service
           └─control
             ├─5987 /bin/bash /usr/share/mysql/mysql-systemd-start post
             └─6029 sleep 1

Jun 12 11:45:46 wkssop-hev7 systemd[1]: Starting MySQL Community Server...
Jun 12 11:45:48 wkssop-hev7 systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE

这基本上是我要遵循的步骤：

if ! service mysql stop ; then
   echo "ignoring failure to stop mysql"
fi

cp config/my.cnf /etc/mysql/my.cnf
mkdir -p /data/mysqldata
chmod 777 /data/mysqldata
cp -R -p /var/lib/mysql/* /data/mysqldata

sed "s/\/var\/lib\/mysql/\/data\/mysqldata/g" /etc/apparmor.d/usr.sbin.mysqld > tmp
mv tmp /etc/apparmor.d/usr.sbin.mysqld
apparmor_parser -r /etc/apparmor.d/usr.sbin.mysqld
/etc/init.d/apparmor reload
service mysql restart

我得到了最后一步重新启动服务的错误，这是无法做到的。

我还在mysql设备配置文件中添加了/sys/设备/system/node/r和/sys/设备/system/节点/** r，因为它们似乎是一个不存在的bug：https://bugs.launchpad.net/ubuntu/+source/mysql-5.7/+bug/1658233

但是现在我在想，我是否应该对: /proc /#/状态做同样的处理，那么我想它实际上必须是/proc吗？所以我想我还是试试吧，结果还是失败了。

journatlctl -xe | tail -30:

-- Subject: Unit mysql.service has begun start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysql.service has begun starting up.
Jun 14 13:28:50 minint-l35opp1 systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE
Jun 14 13:29:18 minint-l35opp1 systemd[1]: Failed to start MySQL Community Server.
-- Subject: Unit mysql.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysql.service has failed.
-- 
-- The result is failed.
Jun 14 13:29:18 minint-l35opp1 systemd[1]: mysql.service: Unit entered failed state.
Jun 14 13:29:18 minint-l35opp1 systemd[1]: mysql.service: Failed with result 'exit-code'.
Jun 14 13:29:18 minint-l35opp1 systemd[1]: mysql.service: Service hold-off time over, scheduling restart.
Jun 14 13:29:18 minint-l35opp1 systemd[1]: Stopped MySQL Community Server.
-- Subject: Unit mysql.service has finished shutting down
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysql.service has finished shutting down.
Jun 14 13:29:18 minint-l35opp1 systemd[1]: Starting MySQL Community Server...
-- Subject: Unit mysql.service has begun start-up
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
-- 
-- Unit mysql.service has begun starting up.
Jun 14 13:29:20 minint-l35opp1 systemd[1]: mysql.service: Main process exited, code=exited, status=1/FAILURE

Answer 1

我最后一个错误是：https://askubuntu.com/a/792857/693474的答案.解决了我的问题。即使我不明白为什么这两个参数在哪里，首先，因为这是一个干净的安装？