Yum install mysql not able to start mysql or mariadb service

 

Sometimes When you run:  yum install mysql
command by default it installs MariaDB not MySQL.

and you are not able to start up mysqld or mariadb.service

you should then try the following command:

sudo yum list installed | grep mariadb
if mariadb-server is missing then you need to run this following command:

sudo yum install mariadb-server
it installs the server package then start the service:

sudo systemctl start mariadb
or:

sudo service mariadb start

————— setting the root password ——————-

sudo /usr/bin/mysql_secure_installation

 

Moving files between windows host and virtualbox VM (CentOs)

Option 1: Before booting up CentOs, go to CentOs VM settings, specify a share folder. Then after logged in to CentOs, create a new directory for example /media/vboxshared and mount that drive using the command sudo mount -t vboxsf SHARENAME /media/vboxshared. Enter your password when it prompts for the password.

Option 2: Before booting up CentOs, add a new Network adapter and select ‘Bridged Adapter’. Then after logged in to CentOs, run the command ifconfig -a | more to get the ip address of that new network adapter. In Windows Host, use WinSCP or FileZilla to transfer the file to CentOs

Install Docker on Oracle Virtualbox CentOS 7

# cd /etc/yum.repos.d/
# wget http://yum.oracle.com/public-yum-ol7.repo
# vi public-yum-ol7.repo

[ol7_latest]
name=Oracle Linux $releasever Latest ($basearch)
baseurl=http://yum.oracle.com/repo/OracleLinux/OL7/latest/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=1

[ol7_UEKR4]
name=Latest Unbreakable Enterprise Kernel Release 4 for Oracle Linux $releasever ($basearch)
baseurl=http://yum.oracle.com/repo/OracleLinux/OL7/UEKR4/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=1

[ol7_addons]
name=Oracle Linux $releasever Add ons ($basearch)
baseurl=http://yum.oracle.com/repo/OracleLinux/OL7/addons/$basearch/
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-oracle
gpgcheck=1
enabled=1

reference link
https://blogs.oracle.com/virtualization/install-docker-on-oracle-linux-7-v2

starting docker service 

# systemctl start docker
# systemctl enable docker
# yum install docker-engine