centos7 升级内核

rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-2.el7.elrepo.noarch.rpm
yum --disablerepo="*" --enablerepo="elrepo-kernel" list available
yum --enablerepo=elrepo-kernel install kernel-ml -y
sed -i 's@GRUB_DEFAULT=.*@GRUB_DEFAULT=0@g' /etc/default/grub
grub2-mkconfig -o /boot/grub2/grub.cfg
yum update -y

###@@@一下是自己使用的 谢谢

sed -i 's@SELINUX=.*@SELINUX=disabled@g' /etc/sysconfig/selinux
systemctl stop firewalld
systemctl disable firewalld
setenforce
yum install chrony -y
systemctl start chronyd
systemctl enable chronyd
echo -e '30 * * * * /usr/bin/systemctl restart chronyd' >> /etc/crontab
systemctl enable crond
systemctl start crond

init 

useradd -d /home/cephd -m cephd
echo "cephd" | passwd --stdin cephd
echo "cephd ALL = (root) NOPASSWD:ALL" | sudo tee /etc/sudoers.d/cephd
chmod  /etc/sudoers.d/cephd