How to install jdk and mysql on centos
1: Environment
2: Download the jdk rpm package locally and upload it to the server (because of this I just started using wget to download directly to the server, and the installation kept reporting errors, so I decided to use this stupid method)
Download address:
jdk is installed by default In /usr/java
Three: Configure environment variables
My machine has installed jdk-8u151-linux-x64 After .rpm, the java –version operation can be performed normally without configuring environment variables, so I did not configure the jdk environment variables. But for the sake of future discomfort, here is a record of how to configure it. The operation is as follows:
Modify the system environment variable file
vi /etc/profile
Append the following content to the file:
java_home=/usr/java/jdk1.8.0_151
jre_home=/usr/java/jdk1.8.0_151/jre
path=$path:$java_home/bin:$ jre_home/bin
classpath=.:$java_home/lib/dt.jar:$java_home/lib/tools.jar:$jre_home/libexport java_home jre_home path classpath
Make the modification effective
[root@localhost ~]# source /etc/profile //使修改立即生效 [root@localhost ~]#echo $path //查看path值
Check the system environment status
[root@localhost ~]# echo $path /usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin:/usr/java/jdk1.8.0_25/bin:/usr/java/jdk1.8.0_25/jre/bin
Four: Install mysql (download and install mysql-server from the official website)
# wget http://dev.mysql.com/get/mysql-community-release-el7-5.noarch.rpm # rpm -ivh mysql-community-release-el7-5.noarch.rpm # yum install mysql-community-server
Restart the mysql service after successful installation.
# service mysqld restart
When installing mysql for the first time, the root account does not have a password.
Set password
mysql> set password for 'root'@'localhost' =password('password'); query ok, 0 rows affected (0.00 sec) mysql>
Five: Configure mysql
1, encoding
The mysql configuration file is /etc/my.cnf
Finally add the encoding configuration
[mysql] default-character-set =utf8
The character encoding here must be consistent with /usr/share/mysql/charsets/index.xml.
2. Remote connection settings
Assign all permissions of all tables in all databases to the root user located at all IP addresses.
mysql> grant all privileges on *.* to root@'%'identified by 'password';
If it is a new user instead of root, you must first create a new user
mysql>create user 'username'@'%' identified by 'password';
Then you can connect remotely.
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