kimsufi下centos7更换内核安装BBR操作记录

买了个二手kimsufi的ks7发现速度不理想,想着使用BBR来加速一下.翻了好多百度记录,只有这个成功.当然也有朋友喜欢使用一键包.

1、yum系统更新

yum -y update

2、查看系统版本

cat /etc/redhat-release

输出如下则表示已升级到7.7

CentOS Linux release 7.7.1908 (Core)

3、安装elrepo并升级内核(命令是一条一条输入的)

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 kernel-ml -y

正常情况下将输出如下信息：

[root@ns3026884 ~]# rpm --import https://www.elrepo.org/RPM-GPG-KEY-elrepo.org
[root@ns3026884 ~]# rpm -Uvh http://www.elrepo.org/elrepo-release-7.0-2.el7.elrepo.noarch.rpm
Retrieving http://www.elrepo.org/elrepo-release-7.0-2.el7.elrepo.noarch.rpm
Retrieving http://elrepo.org/elrepo-release-7.0-4.el7.elrepo.noarch.rpm
Preparing...                          ################################# [100%]
Updating / installing...
   1:elrepo-release-7.0-4.el7.elrepo  ################################# [100%]
[root@ns3026884 ~]# yum --enablerepo=elrepo-kernel install kernel-ml -y
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * elrepo: mirrors.coreix.net
 * elrepo-kernel: mirrors.coreix.net
elrepo                                                                                                    | 2.9 kB  00:00:00     
elrepo-kernel                                                                                             | 2.9 kB  00:00:00     
(1/2): elrepo/primary_db                                                                                  | 467 kB  00:00:00     
(2/2): elrepo-kernel/primary_db                                                                           | 1.9 MB  00:00:00     
Resolving Dependencies
--> Running transaction check
---> Package kernel-ml.x86_64 0:5.6.7-1.el7.elrepo will be installed
--> Processing Dependency: grubby >= 8.28-2 for package: kernel-ml-5.6.7-1.el7.elrepo.x86_64
--> Processing Dependency: /usr/sbin/new-kernel-pkg for package: kernel-ml-5.6.7-1.el7.elrepo.x86_64
--> Processing Dependency: /usr/sbin/new-kernel-pkg for package: kernel-ml-5.6.7-1.el7.elrepo.x86_64
--> Running transaction check
---> Package grubby.x86_64 0:8.28-26.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

=================================================================================================================================
 Package                     Arch                     Version                              Repository                       Size
=================================================================================================================================
Installing:
 kernel-ml                   x86_64                   5.6.7-1.el7.elrepo                   elrepo-kernel                    49 M
Installing for dependencies:
 grubby                      x86_64                   8.28-26.el7                          base                             71 k

Transaction Summary
=================================================================================================================================
Install  1 Package (+1 Dependent package)

Total download size: 49 M
Installed size: 222 M
Downloading packages:
(1/2): grubby-8.28-26.el7.x86_64.rpm                                                                      |  71 kB  00:00:00     
(2/2): kernel-ml-5.6.7-1.el7.elrepo.x86_64.rpm                                                            |  49 MB  00:00:04     
---------------------------------------------------------------------------------------------------------------------------------
Total                                                                                             10 MB/s |  49 MB  00:00:04     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
Warning: RPMDB altered outside of yum.
  Installing : grubby-8.28-26.el7.x86_64                                                                                     1/2 
  Installing : kernel-ml-5.6.7-1.el7.elrepo.x86_64                                                                           2/2 

  Verifying  : kernel-ml-5.6.7-1.el7.elrepo.x86_64                                                                           1/2 
  Verifying  : grubby-8.28-26.el7.x86_64                                                                                     2/2 

Installed:
  kernel-ml.x86_64 0:5.6.7-1.el7.elrepo                                                                                          

Dependency Installed:
  grubby.x86_64 0:8.28-26.el7                                                                                                    

Complete!

安装完成后使用下面命令查看当前已安装的内核:

awk -F\' '$1=="menuentry " {print i++ " : " $2}' /etc/grub2.cfg

返回:

[root@ns3026884 ~]# awk -F\' '$1=="menuentry " {print i++ " : " $2}' /etc/grub2.cfg
0 : CentOS Linux (5.6.7-1.el7.elrepo.x86_64) 7 (Core)
1 : CentOS Linux (4.19-ovh-xxxx-std-ipv6-64) 7 (Core)

把CentOS Linux (4.19.0-1.el7.elrepo.x86_64) 7 (Core)内核设置为默认:

[root@ns3026884 ~]# grub2-set-default 0

重启:

reboot

4、设置BBR

• 编辑(vi教程:https://www.runoob.com/linux/linux-vim.html)

vi /etc/sysctl.conf

• 添加如下内容

net.core.default_qdisc = fq
net.ipv4.tcp_congestion_control = bbr

• 退出vi,执行一下命令,加载系统参数（正常情况下会输出我们之前加入的内容）

sysctl -p

可以看到:

[root@ns3026884 ~]# sysctl -p
net.core.default_qdisc = fq
net.ipv4.tcp_congestion_control = bbr

5、验证bbr是否已经开启

a. 如果

sysctl net.ipv4.tcp_available_congestion_control

返回

net.ipv4.tcp_available_congestion_control = reno cubic bbr

则成功!

b.如果

lsmod | grep bbr

返回形如如下形式的信息即成功

tcp_bbr                20480  2

附言:为了测试 BBR 的网络性能增强, 您可以在 Web 服务器目录中创建一个文件以供下载, 然后, 从台式计算机上的 Web 浏览器测试下载速度。

sudo dd if=/dev/zero of=500mb.zip bs=1024k count=500

最后, 从桌面计算机上的 Web 浏览器访问http://ip/500mb.zip , 然后评估执行下载速度。

更多kimsufi信息请访问:https://woyard.com/kimsufi