How to upgrade and install MySQL5.5 under CentOS6.2-Mysql Tutorial-php.cn

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How to upgrade and install MySQL5.5 under CentOS6.2

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May 28, 2023 am 09:41 AM

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1. First, back up the data. Although the data will not be lost after a successful upgrade, please back it up just to be on the safe side.

sqldump -u xxx -h xxx -p 3306 -p --all-databases > databases.sql

It is best to back up the data files and configuration files.

cp -r /data/mysql mysql-5.1-data

cp /etc/my.cnf my.cnf-5.1

Stop the mysql service after the backup is completed.

service mysqld stop

Okay, let’s get to the point.

2. Uninstall the old version of mysql

yum remove mysql mysql-*

After executing, see if there are any remaining mysql-libs Class

yum list installed | grep mysql

If there is one, you can delete it after confirming that it is useless.

yum remove mysql-libs

Note that deleting mysql-libs may have an impact on some dependent software, which we will not discuss here.

Okay, the uninstallation is basically over.

3. Install mysql5.5

If you are not lazy, it may be better to choose to compile and install.

Here we discuss using yum to install the process of.

After taking many detours, I found that I needed to install some new repos first.

rpm -uvh http://download.fedora.redhat.com/pub/epel/6/i386/epel-release-6-2.noarch.rpm

rpm -uvh http ://mirrors.neusoft.edu.cn/epel/6/i386/epel-release-6-7.noarch.rpm

rpm -uvh http://packages.sw.be/rpmforge-release /rpmforge-release-0.5.2-2.el6.rf.x86_64.rpm

rpm -uvh http://dl.iuscommunity.org/pub/ius/stable/redhat/6/x86_64/epel -release-6-5.noarch.rpm

rpm -uvh http://rpms.famillecollet.com/enterprise/remi-release-6.rpm

At this time, you can run:

yum --enablerepo=remi,remi-test info mysql mysql-server

You will find that the version of mysql is already 5.5.x. Install it without hesitation.

yum --enablerepo=remi,remi-test install mysql mysql-server

The installation ends here. Next comes booting and upgrading.

4. Startup and upgrade

At this time, if you want to start directly, you will most likely get an error. There are two main problems: one is the configuration file, compared with 5.5 Some configurations have been renamed in 5.1. You need to make some improvements based on the startup error log. The second is that mysql_upgrade is not executed.

After ensuring that there is no problem with the configuration file, run:

mysql_upgrade -u root -p

Wait until everything is ok.

Try running mysql again.

service mysqld start

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