网络-二、CentOS基础配置（1.网络与包管理）

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二、基础配置操作

1、网络管理（配置静态地址并进行ssh远程连接）

（1.）静态地址配置

ip地址的配置文件存于etc/sysconfig/network-scripts/下

[root@centos /]# cd /etc/sysconfig/network-scripts/
[root@centos network-scripts]# ls
ifcfg-eth0   ifdown-post      ifup-aliases  ifup-post      init.ipv6-global
ifcfg-lo     ifdown-ppp       ifup-bnep     ifup-ppp       network-functions
ifdown       ifdown-routes    ifup-eth      ifup-routes    network-functions-ipv6
ifdown-bnep  ifdown-sit       ifup-ippp     ifup-sit       test.txt
ifdown-eth   ifdown-Team      ifup-ipv6     ifup-Team
ifdown-ippp  ifdown-TeamPort  ifup-isdn     ifup-TeamPort
ifdown-ipv6  ifdown-tunnel    ifup-plip     ifup-tunnel
ifdown-isdn  ifup             ifup-plusb    ifup-wireless

查看一下ip地址的网口，然后查看一下配置

[root@centos network-scripts]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:16:3e:0c:2c:e6 brd ff:ff:ff:ff:ff:ff
    inet 172.31.79.129/20 brd 172.31.79.255 scope global dynamic eth0
       valid_lft 315005508sec preferred_lft 315005508sec
    inet6 fe80::216:3eff:fe0c:2ce6/64 scope link 
       valid_lft forever preferred_lft forever
[root@centos network-scripts]# cat ifcfg-eth0 
# Created by cloud-init on instance boot automatically, do not edit.
# If you don't want cloud-init genrated automatically,you can disable it in /etc/cloud/cloud.cfg
# For more information, please refer to: https://help.aliyun.com/document_detail/57803.html
#
BOOTPROTO=dhcp
DEVICE=eth0
ONBOOT=yes
STARTMODE=auto
TYPE=Ethernet
USERCTL=no
# 注释：
# ip a：用于显示当前系统中所有网络接口的详细信息，包括每个接口的IP地址、MAC地址、状态、以及其他配置参数 

进行修改静态IP地址（可以参考我另一篇：centos-静态ip及修改主机名）

[root@centos network-scripts]# vi ifcfg-eth0 
[root@centos network-scripts]# systemctl restart network
[root@centos network-scripts]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:16:3e:0c:2c:e6 brd ff:ff:ff:ff:ff:ff
    inet 172.31.79.129/24 brd 172.31.79.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::216:3eff:fe0c:2ce6/64 scope link 
       valid_lft forever preferred_lft forever
[root@centos network-scripts]# cat ifcfg-eth0 
# Created by cloud-init on instance boot automatically, do not edit.
# If you don't want cloud-init genrated automatically,you can disable it in /etc/cloud/cloud.cfg
# For more information, please refer to: https://help.aliyun.com/document_detail/57803.html
#
BOOTPROTO=static
DEVICE=eth0
ONBOOT=yes
STARTMODE=auto
TYPE=Ethernet
USERCTL=no
IPADDR=172.31.79.129
NETMASK=255.255.255.0
GATEWAY=172.31.79.1
DNS1=202.102.227.68
DNS2=202.102.224.68

到此，静态IP配置完成

（2.）IP配置注释

以下是在物理机上的IP配置中的参数注释，上面的是在阿里云ECS中配置的

参数	注释
TYPE=“Ethernet”	表示这是一个使用以太网协议的网络接口
PROXY_METHOD =“none”	指定不使用代理
BROWSER_ONLY=“no”	表示不仅限于浏览器使用
BOOTPROTO=“static”	指定使用静态 IP 地址配置
DEFROUTE=“yes”	指定设置默认路由
IPV4_FAILURE_FATAL=“no”	指定 IPv4 连接失败不会导致致命错误
IPV6INIT=“yes”	启用 IPv6
IPV6_AUTOCONF=“yes”	启用 IPv6 自动配置
IPV6_DEFROUTE=“yes”	指定设置 IPv6 默认路由
IPV6_FAILURE_FATAL=“no”	指定 IPv6 连接失败不会导致致命错误
IPV6_ADDR_GEN_MODE=“stable-privacy”	指定使用稳定的隐私地址生成模式
NAME=“ens33”	指定接口的名称
UUID=“3d078699-517f-44e9-a42c-fc38144e522d”	接口的唯一标识符
DEVICE=“ens33”	指定设备的名称
ONBOOT=“yes”	指定在启动时激活该接口
IPADDR=192.168.101.101	指定 IP 地址为 192.168.101.101
NETMASK=255.255.255.0	指定网络子网掩码为 255.255.255.0
GATEWAY=192.168.101.1	指定网关的 IP 地址为 192.168.101.1
DNS1=192.168.101.1	指定首选 DNS 服务器的 IP 地址为 192.168.101.1
DNS2=8.8.8.8	指定备用 DNS 服务器的 IP 地址为 8.8.8.8

（3.）配置SSH远程连接

SSH，全称为Secure Shell，即安全外壳协议，是一种用于在不安全的网络中提供安全通信的网络协议。

它的主要功能包括：

加密传输：SSH通过加密客户端和服务器之间的通信来保证数据的安全性，防止数据在传输过程中被截获或篡改。
身份认证：SSH允许用户通过密码或者密钥对进行身份验证，确保只有授权的用户才能访问系统。
远程登录：SSH最常见的用途之一是作为远程登录工具，用户可以通过SSH从本地计算机登录到远程服务器上进行操作和管理。
端口转发：SSH还支持端口转发，这允许用户将本地端口上的连接转发到远程服务器的端口，从而在需要时绕过防火墙的限制。

CentOS系统默认已经安装了SSH服务，当你安装CentOS时，系统会自动安装好所有必要的服务和依赖包，以便用户能够进行远程登录和管理

有些特殊情况是需要安装openssh-server的

OpenSSH-server是OpenSSH项目的一部分，而OpenSSH是SSH协议的免费开源实现，它包括客户端和服务器两部分

查看SSH版本

[root@centos /]# rpm -qa | grep ssh
libssh2-1.8.0-3.el7.x86_64
openssh-clients-7.4p1-21.el7.x86_64
openssh-7.4p1-21.el7.x86_64
openssh-server-7.4p1-21.el7.x86_64
# 注释：
#rpm：PM代表"Red Hat Package Manager"，它是一种软件包管理工具。RPM文件通常包含了软件的预编译二进制程序、配置文件、文档等，用于在CentOS系统上安装、升级或删除软件
# rpm -qa：rpm -qa用于列出系统上已安装的所有软件包的名称，qa代表查询
# grep：用于在文本文件中搜索指定的模式（字符串）

关闭防火墙或者方通SSH协议的22端口

# 永久关闭防火墙
[root@centos /]# systemctl stop firewalld
[root@centos /]# systemctl disable firewalld
# 开启防火墙
[root@centos /]# systemctl start firewalld
[root@centos /]# systemctl enable firewalld
# 放通22端口
[root@centos /]# firewall-cmd --zone=public --add-port=22/tcp --permanent
success
[root@centos /]# firewall-cmd --reload
success
# 查看防火墙方通的端口
[root@centos /]# firewall-cmd --list-ports
22/tcp

当然，SElinux也是需要关闭的

SELinux（Security-Enhanced Linux）是一个安全子系统，它为Linux操作系统提供了额外的安全性层，通过强制访问控制 (MAC) 来限制进程的能力，以减少系统遭受内核级攻击的风险

[root@centos /]# cat /etc/selinux/config 

# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=disabled
# SELINUXTYPE= can take one of three values:
#     targeted - Targeted processes are protected,
#     minimum - Modification of targeted policy. Only selected processes are protected. 
#     mls - Multi Level Security protection.
SELINUXTYPE=targeted

查看SSH服务状态（开启和关闭状态）

[root@centos /]# systemctl status sshd
● sshd.service - OpenSSH server daemon
   Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)
   Active: active **(running)** since Mon 2024-03-25 12:30:46 CST; 4 days ago
     Docs: man:sshd(8)
           man:sshd_config(5)
 Main PID: 1193 (sshd)
   CGroup: /system.slice/sshd.service
           └─1193 /usr/sbin/sshd -D

Mar 29 15:12:45 centos sshd[18243]: Accepted password for root from 118.31.243.250 por...sh2
Mar 29 15:12:46 centos sshd[18251]: Accepted password for root from 118.31.243.110 por...sh2
Mar 29 15:13:17 centos sshd[18315]: Accepted password for root from 118.31.243.243 por...sh2
Mar 29 15:13:18 centos sshd[18683]: Accepted password for root from 118.31.243.122 por...sh2
Mar 29 15:13:21 centos sshd[18694]: Accepted password for root from 118.31.243.252 por...sh2
Mar 29 15:13:22 centos sshd[18703]: Accepted password for root from 118.31.243.78 port...sh2
Mar 29 15:13:23 centos sshd[18712]: Accepted password for root from 118.31.243.153 por...sh2
Mar 29 15:13:26 centos sshd[18722]: Accepted password for root from 118.31.243.235 por...sh2
Mar 29 15:13:27 centos sshd[18731]: Accepted password for root from 118.31.243.19 port...sh2
Mar 29 15:13:28 centos sshd[18740]: Accepted password for root from 118.31.243.197 por...sh2
Hint: Some lines were ellipsized, use -l to show in full.
# 注释：
# systemctl status：用于显示系统的状态信息，包括当前正在运行的服务的状态

[root@centos /]# systemctl status sshd
● sshd.service - OpenSSH server daemon
   Loaded: loaded (/usr/lib/systemd/system/sshd.service; enabled; vendor preset: enabled)
   Active: inactive **(dead)** since Fri 2024-03-29 15:38:12 CST; 4s ago
     Docs: man:sshd(8)
           man:sshd_config(5)
  Process: 1193 ExecStart=/usr/sbin/sshd -D $OPTIONS (code=exited, status=0/SUCCESS)
 Main PID: 1193 (code=exited, status=0/SUCCESS)

Mar 29 15:27:24 centos sshd[19433]: Accepted password for root from 118.31.243.108 port 62066 ssh2
Mar 29 15:27:25 centos sshd[19441]: Accepted password for root from 118.31.243.180 port 42932 ssh2
Mar 29 15:28:14 centos sshd[19491]: Accepted password for root from 118.31.243.212 port 20182 ssh2
Mar 29 15:28:16 centos sshd[19500]: Accepted password for root from 118.31.243.55 port 49097 ssh2
Mar 29 15:28:17 centos sshd[19509]: Accepted password for root from 118.31.243.119 port 44536 ssh2
Mar 29 15:28:19 centos sshd[19520]: Accepted password for root from 118.31.243.3 port 47648 ssh2
Mar 29 15:28:20 centos sshd[19530]: Accepted password for root from 118.31.243.154 port 2575 ssh2
Mar 29 15:28:21 centos sshd[19539]: Accepted password for root from 118.31.243.35 port 49280 ssh2
Mar 29 15:38:12 centos systemd[1]: Stopping OpenSSH server daemon...
Mar 29 15:38:12 centos systemd[1]: Stopped OpenSSH server daemon.

需要修改SSH配置的可以在/etc/sysconfig/sshd下修改

[root@centos /]# cat /etc/sysconfig/sshd 
# Configuration file for the sshd service.

# The server keys are automatically generated if they are missing.
# To change the automatic creation uncomment and change the appropriate
# line. Accepted key types are: DSA RSA ECDSA ED25519.
# The default is "RSA ECDSA ED25519"

# AUTOCREATE_SERVER_KEYS=""
# AUTOCREATE_SERVER_KEYS="RSA ECDSA ED25519"

# Do not change this option unless you have hardware random
# generator and you REALLY know what you are doing

SSH_USE_STRONG_RNG=0
# SSH_USE_STRONG_RNG=1

阿里云ECS和物理机的配置是不一样的，还是要看现场实际情况的

2、包管理

（1.）yum软件包管理器

在CentOS中，"yum"是一个软件包管理器，用于安装、升级、删除和管理系统中的软件包

它可以从预配置的软件存储库中获取软件包，并自动解决依赖关系

"yum"还可以快速、方便地安装所需的软件、更新系统以及管理软件包

在CentOS 8及更新版本中，“dnf” 已经成为了"yum"的替代者，但是在很多系统中"yum"命令仍然可用

1. yum clean all - 清理YUM缓存和临时文件

[root@centos /]# yum clean all
Loaded plugins: fastestmirror
Cleaning repos: base epel extras updates

2. yum install - 安装指定的软件包及其依赖项

这里以ntp时间同步服务举例
（从安装到启动）

# yum安装ntp服务
[root@centos /]# yum install -y ntp
Loaded plugins: fastestmirror
Determining fastest mirrors
base                                                                 | 3.6 kB  00:00:00     
epel                                                                 | 4.7 kB  00:00:00     
extras                                                               | 2.9 kB  00:00:00     
updates                                                              | 2.9 kB  00:00:00     
(1/7): epel/x86_64/updateinfo                                        | 1.0 MB  00:00:00     
(2/7): base/7/x86_64/primary_db                                      | 6.1 MB  00:00:00     
(3/7): base/7/x86_64/group_gz                                        | 153 kB  00:00:00     
(4/7): epel/x86_64/group_gz                                          | 100 kB  00:00:00     
(5/7): epel/x86_64/primary_db                                        | 7.0 MB  00:00:00     
(6/7): extras/7/x86_64/primary_db                                    | 254 kB  00:00:00     
(7/7): updates/7/x86_64/primary_db                                   |  26 MB  00:00:00     
Resolving Dependencies
--> Running transaction check
---> Package ntp.x86_64 0:4.2.6p5-29.el7.centos.2 will be installed
--> Processing Dependency: ntpdate = 4.2.6p5-29.el7.centos.2 for package: ntp-4.2.6p5-29.el7.centos.2.x86_64
--> Processing Dependency: libopts.so.25()(64bit) for package: ntp-4.2.6p5-29.el7.centos.2.x86_64
--> Running transaction check
---> Package autogen-libopts.x86_64 0:5.18-5.el7 will be installed
---> Package ntpdate.x86_64 0:4.2.6p5-29.el7.centos.2 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

============================================================================================
 Package                 Arch           Version                          Repository    Size
============================================================================================
Installing:
 ntp                     x86_64         4.2.6p5-29.el7.centos.2          base         549 k
Installing for dependencies:
 autogen-libopts         x86_64         5.18-5.el7                       base          66 k
 ntpdate                 x86_64         4.2.6p5-29.el7.centos.2          base          87 k

Transaction Summary
============================================================================================
Install  1 Package (+2 Dependent packages)

Total download size: 701 k
Installed size: 1.6 M
Downloading packages:
(1/3): ntp-4.2.6p5-29.el7.centos.2.x86_64.rpm                        | 549 kB  00:00:00     
(2/3): ntpdate-4.2.6p5-29.el7.centos.2.x86_64.rpm                    |  87 kB  00:00:00     
(3/3): autogen-libopts-5.18-5.el7.x86_64.rpm                         |  66 kB  00:00:00     
--------------------------------------------------------------------------------------------
Total                                                       3.9 MB/s | 701 kB  00:00:00     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : autogen-libopts-5.18-5.el7.x86_64                                        1/3 
  Installing : ntpdate-4.2.6p5-29.el7.centos.2.x86_64                                   2/3 
  Installing : ntp-4.2.6p5-29.el7.centos.2.x86_64                                       3/3 
warning: /etc/ntp.conf created as /etc/ntp.conf.rpmnew
  Verifying  : ntpdate-4.2.6p5-29.el7.centos.2.x86_64                                   1/3 
  Verifying  : ntp-4.2.6p5-29.el7.centos.2.x86_64                                       2/3 
  Verifying  : autogen-libopts-5.18-5.el7.x86_64                                        3/3 

Installed:
  ntp.x86_64 0:4.2.6p5-29.el7.centos.2                                                      

Dependency Installed:
  autogen-libopts.x86_64 0:5.18-5.el7        ntpdate.x86_64 0:4.2.6p5-29.el7.centos.2       

Complete!

# systemctl三连，启动，开机自启，查看状态
[root@centos /]# systemctl start ntpd
[root@centos /]# systemctl enable ntpd
Created symlink from /etc/systemd/system/multi-user.target.wants/ntpd.service to /usr/lib/systemd/system/ntpd.service.
[root@centos /]# systemctl status ntpd
● ntpd.service - Network Time Service
   Loaded: loaded (/usr/lib/systemd/system/ntpd.service; enabled; vendor preset: disabled)
   Active: active (running) since Fri 2024-03-29 16:16:45 CST; 13s ago
 Main PID: 22650 (ntpd)
   CGroup: /system.slice/ntpd.service
           └─22650 /usr/sbin/ntpd -u ntp:ntp -g

Mar 29 16:16:45 centos systemd[1]: Starting Network Time Service...
Mar 29 16:16:45 centos systemd[1]: Started Network Time Service.
Mar 29 16:16:45 centos ntpd[22650]: proto: precision = 0.044 usec
Mar 29 16:16:45 centos ntpd[22650]: 0.0.0.0 c01d 0d kern kernel time sync enabled

3. yum search - 搜索指定名称或关键字的软件包，列出所有相关软件包的详细信息

这里以sshd服务为例

[root@centos /]# yum search sshd
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
====================================== Matched: sshd =======================================
fail2ban.noarch : Daemon to ban hosts that cause multiple authentication errors
gsi-openssh-server.x86_64 : SSH server daemon with GSI authentication
jsch.noarch : Pure Java implementation of SSH2
libnss-mysql.x86_64 : NSS library for MySQL
openssh-server.x86_64 : An open source SSH server daemon

4. yum update - 更新指定的软件包及其依赖项到最新版本

# 查看可用于更新的软件包
[root@centos /]# yum check-update
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile

NetworkManager.x86_64                     1:1.18.8-2.el7_9                           updates
NetworkManager-libnm.x86_64               1:1.18.8-2.el7_9                           updates
NetworkManager-team.x86_64                1:1.18.8-2.el7_9                           updates
NetworkManager-tui.x86_64                 1:1.18.8-2.el7_9                           updates

# 更新zlib到最新版本
[root@centos /]# yum update zlib
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
Resolving Dependencies
--> Running transaction check
---> Package zlib.x86_64 0:1.2.7-18.el7 will be updated
---> Package zlib.x86_64 0:1.2.7-21.el7_9 will be an update
--> Finished Dependency Resolution

Dependencies Resolved

============================================================================================
 Package          Arch               Version                      Repository           Size
============================================================================================
Updating:
 zlib             x86_64             1.2.7-21.el7_9               updates              90 k

Transaction Summary
============================================================================================
Upgrade  1 Package

Total download size: 90 k
Is this ok [y/d/N]: y
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
zlib-1.2.7-21.el7_9.x86_64.rpm                                       |  90 kB  00:00:00     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Updating   : zlib-1.2.7-21.el7_9.x86_64                                               1/2 
  Cleanup    : zlib-1.2.7-18.el7.x86_64                                                 2/2 
  Verifying  : zlib-1.2.7-21.el7_9.x86_64                                               1/2 
  Verifying  : zlib-1.2.7-18.el7.x86_64                                                 2/2 

Updated:
  zlib.x86_64 0:1.2.7-21.el7_9                                                              

Complete!

5. yum remove - 卸载指定的软件包及其依赖项

这里还是以ntp为例

[root@centos /]# yum remove ntp
Loaded plugins: fastestmirror
Resolving Dependencies
--> Running transaction check
---> Package ntp.x86_64 0:4.2.6p5-29.el7.centos.2 will be erased
--> Finished Dependency Resolution

Dependencies Resolved

============================================================================================
 Package        Arch              Version                            Repository        Size
============================================================================================
Removing:
 ntp            x86_64            4.2.6p5-29.el7.centos.2            @base            1.4 M

Transaction Summary
============================================================================================
Remove  1 Package

Installed size: 1.4 M
Is this ok [y/N]: y
Downloading packages:
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Erasing    : ntp-4.2.6p5-29.el7.centos.2.x86_64                                       1/1 
warning: /etc/ntp.conf saved as /etc/ntp.conf.rpmsave
  Verifying  : ntp-4.2.6p5-29.el7.centos.2.x86_64                                       1/1 

Removed:
  ntp.x86_64 0:4.2.6p5-29.el7.centos.2                                                      

Complete!

（2.）rpm软件包管理

在CentOS中，“rpm"代表"Red Hat Package Manager”，它是一个用于在Red Hat系统和基于Red Hat的发行版（如CentOS）中安装、升级和管理软件包的命令行工具

"rpm"可以通过预编译的二进制软件包文件（后缀为.rpm）来安装软件，并提供了一系列选项和参数来管理系统中的软件包，例如查询、升级、卸载等操作

1. rpm -qa - 列出所有已安装的RPM包

[root@centos /]# rpm -qa
kbd-1.15.5-15.el7.x86_64
setup-2.8.71-11.el7.noarch
ncurses-base-5.9-14.20130511.el7_4.noarch
parted-3.1-32.el7.x86_64
nspr-4.21.0-1.el7.x86_64
bash-4.2.46-34.el7.x86_64
iwl6050-firmware-41.28.5.1-76.el7.noarch
iwl2030-firmware-18.168.6.1-76.el7.noarch
libuuid-2.23.2-63.el7.x86_64
iwl135-firmware-18.168.6.1-76.el7.noarch
chkconfig-1.7.4-1.el7.x86_64
iwl105-firmware-18.168.6.1-76.el7.noarch

这里只列出一小部分的rpm包

2. rpm -q - 查询一个已安装的RPM包的信息

[root@centos /]# rpm -q bash
bash-4.2.46-34.el7.x86_64

3. rpm -qi - 显示一个已安装的RPM包的详细信息

[root@centos /]# rpm -qi bash
Name        : bash
Version     : 4.2.46
Release     : 34.el7
Architecture: x86_64
Install Date: Mon 14 Sep 2020 03:14:34 PM CST
Group       : System Environment/Shells
Size        : 3667724
License     : GPLv3+
Signature   : RSA/SHA256, Sat 04 Apr 2020 04:49:07 AM CST, Key ID 24c6a8a7f4a80eb5
Source RPM  : bash-4.2.46-34.el7.src.rpm
Build Date  : Wed 01 Apr 2020 10:19:58 AM CST
Build Host  : x86-01.bsys.centos.org
Relocations : (not relocatable)
Packager    : CentOS BuildSystem <http://bugs.centos.org>
Vendor      : CentOS
URL         : http://www.gnu.org/software/bash
Summary     : The GNU Bourne Again shell
Description :
The GNU Bourne Again shell (Bash) is a shell or command language
interpreter that is compatible with the Bourne shell (sh). Bash
incorporates useful features from the Korn shell (ksh) and the C shell
(csh). Most sh scripts can be run by bash without modification.

4. rpm -ql - 列出一个已安装的RPM包的所有文件

[root@centos /]# rpm -ql bash
/etc/skel/.bash_logout
/etc/skel/.bash_profile
/etc/skel/.bashrc
/usr/bin/alias
/usr/bin/bash
/usr/bin/bashbug
/usr/bin/bashbug-64
/usr/bin/bg
/usr/bin/cd
/usr/bin/command
/usr/bin/fc
/usr/bin/fg
/usr/bin/getopts
/usr/bin/jobs
/usr/bin/read
/usr/bin/sh

5. rpm -qf - 查找包含特定文件的RPM包

# 只列出rpm包名称
[root@centos /]# rpm -qf /bin/ls
coreutils-8.22-24.el7.x86_64

# 列出 /usr/bin/ 目录下每个文件的提供软件包
[root@centos /]# rpm -qf /usr/bin/*
coreutils-8.22-24.el7.x86_64
python3-devel-3.6.8-13.el7.x86_64
python3-devel-3.6.8-13.el7.x86_64
perl-5.16.3-295.el7.x86_64
binutils-2.27-43.base.el7_8.1.x86_64
bash-4.2.46-34.el7.x86_64
man-db-2.6.3-11.el7.x86_64
binutils-2.27-43.base.el7_8.1.x86_64
coreutils-8.22-24.el7.x86_64
binutils-2.27-43.base.el7_8.1.x86_64

6. rpm -ivh - 安装一个RPM包

# 首先下载nginx的rpm包，可以wget直接下载（可以连接外网的情况下）否则只能现在有网的电脑上下载，然后cp到这台主机上
[root@centos ~]# wget http://nginx.org/packages/centos/7/noarch/RPMS/nginx-release-centos-7-0.el7.ngx.noarch.rpm
--2024-03-29 18:20:52--  http://nginx.org/packages/centos/7/noarch/RPMS/nginx-release-centos-7-0.el7.ngx.noarch.rpm
Resolving nginx.org (nginx.org)... 3.125.197.172, 52.58.199.22, 2a05:d014:5c0:2601::6, ...
Connecting to nginx.org (nginx.org)|3.125.197.172|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 4680 (4.6K) [application/x-redhat-package-manager]
Saving to: ‘nginx-release-centos-7-0.el7.ngx.noarch.rpm’

100%[================================================================================================================================================>] 4,680       --.-K/s   in 0s      

2024-03-29 18:20:54 (382 MB/s) - ‘nginx-release-centos-7-0.el7.ngx.noarch.rpm’ saved [4680/4680]

[root@centos ~]# ls
nginx-release-centos-7-0.el7.ngx.noarch.rpm  ntpsec-1.2.3  ntpsec-1.2.3.tar.gz

# 进行安装下载好的nginx.rpm包
[root@centos ~]# rpm -ivh nginx-release-centos-7-0.el7.ngx.noarch.rpm 
warning: nginx-release-centos-7-0.el7.ngx.noarch.rpm: Header V4 RSA/SHA1 Signature, key ID 7bd9bf62: NOKEY
Preparing...                          ################################# [100%]
Updating / installing...
   1:nginx-release-centos-7-0.el7.ngx ################################# [100%]
# 注释：nginx-release-centos-7-0.el7.ngx.noarch.rpm 是一个用于安装NGINX的官方存储库配置包。它将NGINX的官方存储库添加到您的CentOS系统中，以便您可以使用yum或dnf来安装NGINX并获得自动更新。当安装 nginx-release-centos-7-0.el7.ngx.noarch.rpm 后，系统将接受NGINX官方存储库的签名，并使系统能够通过yum或dnf来安装NGINX软件包

# 安装nginx
[root@centos ~]# yum install nginx
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
Resolving Dependencies
--> Running transaction check
---> Package nginx.x86_64 1:1.24.0-1.el7.ngx will be installed
--> Finished Dependency Resolution

Dependencies Resolved

============================================================================================
 Package          Arch              Version                          Repository        Size
============================================================================================
Installing:
 nginx            x86_64            1:1.24.0-1.el7.ngx               nginx            804 k

Transaction Summary
============================================================================================
Install  1 Package

Total download size: 804 k
Installed size: 2.8 M
Is this ok [y/d/N]: y
Downloading packages:
nginx-1.24.0-1.el7.ngx.x86_64.rpm                                    | 804 kB  00:00:02     
Running transaction check
Running transaction test
Transaction test succeeded
Running transaction
  Installing : 1:nginx-1.24.0-1.el7.ngx.x86_64                                          1/1 
----------------------------------------------------------------------

Thanks for using nginx!

Please find the official documentation for nginx here:
* https://nginx.org/en/docs/

Please subscribe to nginx-announce mailing list to get
the most important news about nginx:
* https://nginx.org/en/support.html

Commercial subscriptions for nginx are available on:
* https://nginx.com/products/

----------------------------------------------------------------------
  Verifying  : 1:nginx-1.24.0-1.el7.ngx.x86_64                                          1/1 

Installed:
  nginx.x86_64 1:1.24.0-1.el7.ngx                                                           

Complete!

# systemctl四连，启动，自启，状态，停止
[root@centos ~]# systemctl start nginx
[root@centos ~]# systemctl enable nginx
Created symlink from /etc/systemd/system/multi-user.target.wants/nginx.service to /usr/lib/systemd/system/nginx.service.
[root@centos ~]# systemctl status nginx
● nginx.service - nginx - high performance web server
   Loaded: loaded (/usr/lib/systemd/system/nginx.service; enabled; vendor preset: disabled)
   Active: active (running) since Fri 2024-03-29 21:14:47 CST; 14s ago
     Docs: http://nginx.org/en/docs/
 Main PID: 7276 (nginx)
   CGroup: /system.slice/nginx.service
           ├─7276 nginx: master process /usr/sbin/nginx -c /etc/nginx/nginx.conf
           ├─7277 nginx: worker process
           └─7278 nginx: worker process

Mar 29 21:14:47 centos systemd[1]: Starting nginx - high performance web server...
Mar 29 21:14:47 centos systemd[1]: Started nginx - high performance web server.
[root@centos ~]# systemctl stop nginx
[root@centos ~]# systemctl status nginx
● nginx.service - nginx - high performance web server
   Loaded: loaded (/usr/lib/systemd/system/nginx.service; enabled; vendor preset: disabled)
   Active: inactive (dead) since Fri 2024-03-29 21:15:10 CST; 2s ago
     Docs: http://nginx.org/en/docs/
  Process: 7400 ExecStop=/bin/sh -c /bin/kill -s TERM $(/bin/cat /var/run/nginx.pid) (code=exited, status=0/SUCCESS)
 Main PID: 7276 (code=exited, status=0/SUCCESS)

Mar 29 21:14:47 centos systemd[1]: Starting nginx - high performance web server...
Mar 29 21:14:47 centos systemd[1]: Started nginx - high performance web server.
Mar 29 21:15:10 centos systemd[1]: Stopping nginx - high performance web server...
Mar 29 21:15:10 centos systemd[1]: Stopped nginx - high performance web server.

7. rpm -e - 卸载一个已安装的RPM包

[root@centos ~]# rpm -e nginx
[root@centos ~]# rpm -qa | grep nginx
nginx-release-centos-7-0.el7.ngx.noarch
[root@centos ~]# systemctl status nginx
Unit nginx.service could not be found.

3、注释总结

---

4、权限管理（用户、文本等）

ip a	用于显示当前系统中所有网络接口的详细信息，包括每个接口的IP地址、MAC地址、状态、以及其他配置参数
cat	用于查看文本文件内容
vi	是一种编辑工具，一般自带与系统之中，有的系统是
systemctl stop	停止运行服务
systemctl restart	重新启动服务
systemctl start	启动服务
systemctl disable	永久关闭服务
systemctl enable	开机自启服务
rpm	PM代表"Red Hat Package Manager"，它是一种软件包管理工具。RPM文件通常包含了软件的预编译二进制程序、配置文件、文档等，用于在CentOS系统上安装、升级或删除软件
rpm -qa	用于列出系统上已安装的所有软件包的名称，qa代表查询
grep	用于在文本文件中搜索指定的模式（字符串）
systemctl status	用于显示系统的状态信息，包括当前正在运行的服务的状态
TYPE=“Ethernet”	表示这是一个使用以太网协议的网络接口
PROXY_METHOD =“none”	指定不使用代理
BROWSER_ONLY=“no”	表示不仅限于浏览器使用
BOOTPROTO=“static”	指定使用静态 IP 地址配置
DEFROUTE=“yes”	指定设置默认路由
IPV4_FAILURE_FATAL=“no”	指定 IPv4 连接失败不会导致致命错误
IPV6INIT=“yes”	启用 IPv6
IPV6_AUTOCONF=“yes”	启用 IPv6 自动配置
IPV6_DEFROUTE=“yes”	指定设置 IPv6 默认路由
IPV6_FAILURE_FATAL=“no”	指定 IPv6 连接失败不会导致致命错误
IPV6_ADDR_GEN_MODE=“stable-privacy”	指定使用稳定的隐私地址生成模式
NAME=“ens33”	指定接口的名称
UUID=“3d078699-517f-44e9-a42c-fc38144e522d”	接口的唯一标识符
DEVICE=“ens33”	指定设备的名称
ONBOOT=“yes”	指定在启动时激活该接口
IPADDR=192.168.101.101	指定 IP 地址为 192.168.101.101
NETMASK=255.255.255.0	指定网络子网掩码为 255.255.255.0
GATEWAY=192.168.101.1	指定网关的 IP 地址为 192.168.101.1
DNS1=192.168.101.1	指定首选 DNS 服务器的 IP 地址为 192.168.101.1
DNS2=8.8.8.8	指定备用 DNS 服务器的 IP 地址为 8.8.8.8