在一測試伺服器（centos linux release 7.2.1511）上安裝mysql 5.6（5.6.19 mysql community server）時遇到下面錯誤，這個是因為centos 7的預設資料庫已經不再是mysql了，而是mariadb. mysql安裝時的mysql lib庫與mariadb的庫、包衝突了，如下詳情所示（省略了大量日誌）
[root@azrlnx06 tmp]# rpm -ivh mysql-server-advanced-5.6.20-1.rhel5.x86_64.rpm preparing... ################################# [100%] file /usr/share/mysql/czech/errmsg.sys from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64 file /usr/share/mysql/danish/errmsg.sys from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64 file /usr/share/mysql/dutch/errmsg.sys from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64 file /usr/share/mysql/english/errmsg.sys from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64 file /usr/share/mysql/estonian/errmsg.sys from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64 file /usr/share/mysql/french/errmsg.sys from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64 file /usr/share/mysql/german/errmsg.sys from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64 file /usr/share/mysql/greek/errmsg.sys from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64 ........................................................................................................................................................................ file /usr/share/mysql/charsets/macroman.xml from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64 file /usr/share/mysql/charsets/swe7.xml from install of mysql-server-advanced-5.6.20-1.rhel5.x86_64 conflicts with file from package mariadb-libs-1:5.5.50-1.el7_2.x86_64
檢查是否存在mariadb的相關組件,然後刪除mariadb相關組件。如下所示：
[root@azrlnx06 mysql]# more /etc/redhat-release centos linux release 7.2.1511 (core) [root@azrlnx06 mysql]# rpm -qa |grep mariadb mariadb-libs-5.5.50-1.el7_2.x86_64 [root@azrlnx06 mysql]# rpm -e mariadb-libs-5.5.50-1.el7_2.x86_64 error: failed dependencies: libmysqlclient.so.18()(64bit) is needed by (installed) postfix-2:2.10.1-6.el7.x86_64 libmysqlclient.so.18(libmysqlclient_18)(64bit) is needed by (installed) postfix-2:2.10.1-6.el7.x86_64 [root@azrlnx06 mysql]# rpm -e mariadb-libs-5.5.50-1.el7_2.x86_64 --nodeps
當然此處刪除mariadb-libs-5.5.50-1.el7_2.x86_64元件時遇到依賴錯誤，遂強制刪除該元件，最好使用yum刪除mariadb相關元件。然後重新安裝mysql時遇到"error: mysql-server-advanced-5.6.20-1.rhel5.x86_64: install failed"錯誤，如下：
[root@azrlnx06 mysql]# cd /tmp [root@azrlnx06 tmp]# ls hsperfdata_azrlnx06 jirasetup mysql-server-advanced-5.6.20-1.rhel5.x86_64.rpm [root@azrlnx06 tmp]# rpm -ivh mysql-server-advanced-5.6.20-1.rhel5.x86_64.rpm preparing... ################################# [100%] updating / installing... 1:mysql-server-advanced-5.6.20-1.rh################################# [100%] error: unpacking of archive failed on file /usr/bin/innochecksum;582535c8: cpio: read failed - no such file or directory error: mysql-server-advanced-5.6.20-1.rhel5.x86_64: install failed [root@azrlnx06 tmp]# clip_image001
對這個錯誤有點莫名其妙，卸載mymysql相關元件後，重新安裝mysql，發現缺少perl相關模組。如下所示：
[root@azrlnx06 jirasetup]# rpm -ivh mysql-server-advanced-5.6.20-1.rhel5.x86_64.rpm preparing... ################################# [100%] updating / installing... 1:mysql-server-advanced-5.6.20-1.rh################################# [100%] fatal error: please install the following perl modules before executing /usr/bin/mysql_install_db: data::dumper [root@azrlnx06 jirasetup]#
使用yum安裝了perl perl-devel相關套件（注意：此處安裝mysql時，沒有輸出安裝相關detail的信息，是因為perl相關模組沒有安裝的緣故，此處還漏掉了安裝perl-data-dumper）
[root@azrlnx06 jirasetup]# yum install -y perl perl-devel
安裝完perl相關元件後，重新安裝mysql，如下所示，安裝成功，但沒有輸出安裝相關detail的資訊（因為沒有安裝perl -data-dumper），啟動mysql報錯
root@azrlnx06 jirasetup]# rpm -ivh mysql-server-advanced-5.6.20-1.rhel5.x86_64.rpm preparing... ################################# [100%] updating / installing... 1:mysql-server-advanced-5.6.20-1.rh################################# [100%] [root@azrlnx06 jirasetup]# rpm -ivh mysql-client-advanced-5.6.20-1.rhel5.x86_64.rpm preparing... ################################# [100%] updating / installing... 1:mysql-client-advanced-5.6.20-1.rh################################# [100%] [root@azrlnx06 ~]# service mysql start starting mysql............. error! the server quit without updating pid file (/var/lib/mysql/azrlnx06.pid). [root@azrlnx06 ~]#
找到mysql的錯誤日誌，然後檢查/var/lib/mysql/azrlnx06.err錯誤日誌，發現如下錯誤訊息：
[root@azrlnx06 mysql]# find / -name *.err /var/lib/mysql/azrlnx06.err /var/log/azure/microsoft.ostcextensions.linuxdiagnostic/2.3.9011/mdsd.err /var/log/azure/microsoft.ostcextensions.linuxdiagnostic/2.3.9013/mdsd.err /var/log/mdsd/mdsd.err [root@azrlnx06 mysql]# more /var/lib/mysql/azrlnx06.err 161111 03:28:25 mysqld_safe starting mysqld daemon with databases from /var/lib/mysql 2016-11-11 03:28:25 0 [warning] timestamp with implicit default value is deprecated. please use --explicit_defaults_for_timestamp server option (see documentation for more details). 2016-11-11 03:28:25 2144 [note] plugin 'federated' is disabled. /usr/sbin/mysqld: table 'mysql.plugin' doesn't exist 2016-11-11 03:28:25 2144 [error] can't open the mysql.plugin table. please run mysql_upgrade to create it. 2016-11-11 03:28:25 2144 [note] innodb: using atomics to ref count buffer pool pages 2016-11-11 03:28:25 2144 [note] innodb: the innodb memory heap is disabled 2016-11-11 03:28:25 2144 [note] innodb: mutexes and rw_locks use gcc atomic builtins 2016-11-11 03:28:25 2144 [note] innodb: memory barrier is not used 2016-11-11 03:28:25 2144 [note] innodb: compressed tables use zlib 1.2.3 2016-11-11 03:28:25 2144 [note] innodb: using linux native aio 2016-11-11 03:28:25 2144 [note] innodb: using cpu crc32 instructions 2016-11-11 03:28:25 2144 [note] innodb: initializing buffer pool, size = 128.0m 2016-11-11 03:28:25 2144 [note] innodb: completed initialization of buffer pool 2016-11-11 03:28:25 2144 [note] innodb: the first specified data file ./ibdata1 did not exist: a new database to be created! 2016-11-11 03:28:25 2144 [note] innodb: setting file ./ibdata1 size to 12 mb 2016-11-11 03:28:25 2144 [note] innodb: database physically writes the file full: wait... 2016-11-11 03:28:26 2144 [note] innodb: setting log file ./ib_logfile101 size to 48 mb 2016-11-11 03:28:31 2144 [note] innodb: setting log file ./ib_logfile1 size to 48 mb 2016-11-11 03:28:37 2144 [note] innodb: renaming log file ./ib_logfile101 to ./ib_logfile0 2016-11-11 03:28:37 2144 [warning] innodb: new log files created, lsn=45781 2016-11-11 03:28:37 2144 [note] innodb: doublewrite buffer not found: creating new 2016-11-11 03:28:37 2144 [note] innodb: doublewrite buffer created 2016-11-11 03:28:37 2144 [note] innodb: 128 rollback segment(s) are active. 2016-11-11 03:28:37 2144 [warning] innodb: creating foreign key constraint system tables. 2016-11-11 03:28:37 2144 [note] innodb: foreign key constraint system tables created 2016-11-11 03:28:37 2144 [note] innodb: creating tablespace and datafile system tables. 2016-11-11 03:28:38 2144 [note] innodb: tablespace and datafile system tables created. 2016-11-11 03:28:38 2144 [note] innodb: waiting for purge to start 2016-11-11 03:28:38 2144 [note] innodb: 5.6.20 started; log sequence number 0 2016-11-11 03:28:38 2144 [warning] no existing uuid has been found, so we assume that this is the first time that this server has been started. generating a new uuid: ef3b0cd5-a7be-11e6-98b3-000d3a8062fe. 2016-11-11 03:28:38 2144 [note] rsa private key file not found: /var/lib/mysql//private_key.pem. some authentication plugins will not work. 2016-11-11 03:28:38 2144 [note] rsa public key file not found: /var/lib/mysql//public_key.pem. some authentication plugins will not work. 2016-11-11 03:28:38 2144 [note] server hostname (bind-address): '*'; port: 3306 2016-11-11 03:28:38 2144 [note] ipv6 is available. 2016-11-11 03:28:38 2144 [note] - '::' resolves to '::'; 2016-11-11 03:28:38 2144 [note] server socket created on ip: '::'. 2016-11-11 03:28:38 2144 [error] fatal error: can't open and lock privilege tables: table 'mysql.user' doesn't exist 161111 03:28:38 mysqld_safe mysqld from pid file /var/lib/mysql/azrlnx06.pid ended clip_image002
搜索了一些相關資料，應該是perl-data-dumper模組沒有安裝，導致安裝過程中，初始化資料庫失敗，所以啟動mysql服務時，找不到相關係統表。具體參考官方文件mysql-server rpm does not install perl-data-dumper as a dependency
description:
mysql-server requires perl-data-dumper to function 。 initial database, the mysql service could not be started.
#how to repeat:
on a linux server, make sure there is no perl-data-dumper installed. install mysql-server using yum. there should be error message complaining database could not be created.
suggested fix:
add perl-data-dumper as a dependency of dependency of the rpm package
解決方法：
1：安裝perl-data-dumper模組。
[root@azrlnx06 mysql]# yum install -y perl-data-dumper
2：初始化資料庫
[root@azrlnx06 mysql]# sudo mysql_install_db --user=mysql --basedir=/usr/ --ldata=/var/lib/mysql/ clip_image003
[root@azrlnx06 mysql]# service mysql start starting mysql. success! [root@azrlnx06 mysql]# /usr//bin/mysqladmin -u root password 'qwe!23' warning: using a password on the command line interface can be insecure.
當然也可以卸載mysql，然後重新安裝，就能看到安裝過程輸出的detail資訊輸出了。
以上是CentOS7安裝MySQL5.6遇到的問題有哪些的詳細內容。更多資訊請關注PHP中文網其他相關文章！
