1:首先yum update -y更新到最新CentOS 7.3 1611
yum -y update
cat /etc/redhat-release
CentOS Linux release 7.3.1611 (Core)
2: 安装elrepo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
然后先rpm -qa |grep kernel
先卸载旧的kernel-headers,kernel-tools, kernel-tools-libs,只保留内核,
yum remove kernel-headers kernel-tools kernel-tools-libs
然后yum –enablerepo=elrepo-kernel install kernel-ml
就会安装elrepo正式版4.9内核,跟着再安装kernel-ml-headers kernel-ml-tools kernel-ml-tools-libs,
yum –enablerepo=elrepo-kernel install kernel-ml kernel-ml-headers kernel-ml-tools kernel-ml-tools-libs
然后
awk -F\’ ‘1==”menuentry ” {print2}’ /etc/grub2.cfg
看看内核启动顺序,然后
grub2-set-default 0
把kernel-ml 4.9设为默认,重启
3:跟着vim /etc/sysctl.conf
加两行:
net.core.default_qdisc = fq
net.ipv4.tcp_congestion_control = bbr
sysctl -p生效,就ok了。
这样是肯定不会挂的。
centos 6 换4.9内核方法:
rpm –import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
rpm -Uvh http://www.elrepo.org/elrepo-release-6-6.el6.elrepo.noarch.rpm
yum –enablerepo=elrepo-kernel install kernel-ml -y
vi /etc/grub.conf 把default=改成0
reboot
uname -r 看看是不是4.9
步骤2可以简化为
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 –enablerepo=elrepo-kernel install -y kernel-ml