云计算学习路线教程大纲课件：网络管理基础

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Network interface names

Traditionally, network interfaces in Linux are enumerated as eth0, eth2, eth3, and so on. However, the mechanism which

sets these names can cause changes to which interface gets which name as devices are added and removed.

The default naming behavior in Red Hat Enterprise Linux 7 is to assign fixed names based on firmware, device topology,

and device type.

Interface names have the following characters:

Ethernet interfaces begin with en, WLAN interfaces begin with wl, and WWAN interfaces begin with ww.

The next character(s) represents the type of adapter with an o for on-board, s for hotplug slot, and p for PCI geographic location.

Not used by default but also available to administrators, an x is used to incorporate a MAC address.

Finally, a number N is used to represent an index, ID, or port.

If the fixed name cannot be determined, the traditional names such as ethN will be used.

For example, the first embedded network interface may be named eno1 and a PCI card network interface may be named enp2s0.

The new names make it easier to distinguish the relationship between a port and its name if the user knows both, but the

trade off is that users cannot assume a system with one interface calls that interface eth0.

使用NetworkManager管理网络

网络管理器（NetworkManager）是一个动态网络的控制器与配置系统，它用于当网络设备可用时保持设备和连接开启并激活

默认情况下，CentOS/RHEL 7 已安装网络管理器，并处于启用状态。

device 设备，物理设备 例如enp2s0,virbr0,team0

connection 连接，逻辑设置 指的是一套具体配置方案

多个connection可以应用到同一个device，但同一时间只能启用其中一个connection。

这样的好处是针对一个网络接口，可以设置多个网络连接，比如静态IP和动态IP，再根据需要up相应的connection

NetworkManager提供的工具

nmcli, nmtui, nm-connect-editor

1. 方法一： 修改ip/netmask/dns/gateway[了解]

[root@tianyun ~]# nmcli connection add con-name enp2s0-auto autoconnect yes ifname enp2s0 type ethernet

[root@tianyun ~]# nmcli connection add con-name enp2s0-gun autoconnect yes ifname enp2s0 type ethernet ip4 10.10.10.10/24 gw4 10.10.10.254

[root@tianyun ~]# nmcli connection show enp2s0-auto |grep ipv4.me

ipv4.method: auto

[root@tianyun ~]# nmcli connection show enp2s0-gun |grep ipv4.me

ipv4.method: manual

[root@tianyun ~]# ls /etc/sysconfig/network-s/

ifcfg-enp2s0 ifdown-ippp ifdown-TeamPort ifup-ipv6 ifup-Team

ifcfg-enp2s0-auto ifdown-ipv6 ifdown-tunnel ifup-isdn ifup-TeamPort

ifcfg-enp2s0-gun ifdown-isdn ifup ifup-plip ifup-tunnel

[root@tianyun ~]# nmcli connection up enp2s0-auto

[root@tianyun ~]# nmcli connection delete enp2s0-auto

[root@tianyun ~]# nmcli connection modify enp2s0-gun ipv4.method a

[root@tianyun ~]# nmcli connection modify enp2s0-gun ipv4.method m

[root@tianyun ~]# nmcli connection modify enp2s0-gun +ipv4.addresses 20.20.20.20/24

[root@tianyun ~]# nmcli connection modify enp2s0-gun +ipv4.dns 114.114.114.114

[root@tianyun ~]# nmcli connection show enp2s0-gun |grep ipv4.add

ipv4.addresses: 10.10.10.10/24, 20.20.20.20/24

2. 方法二：修改ip/netmask/dns/gateway

[root@tianyun ~]# vim /etc/sysconfig/network-s/ifcfg-enp2s0

NAME="enp2s0"

DEVICE="enp2s0"

ONBOOT=yes

NETBOOT=yes

BOOTPROTO=none

IPADDR=172.16.120.246

PREFIX=24

IPADDR1=192.168.200.246

PREFIX1=24

GATEWAY=172.16.120.254

DNS1=8.8.8.8

DNS2=114.114.114.114

[root@tianyun ~]# nmcli con reload

[root@tianyun ~]# nmcli con down enp2s0; nmcli con up enp2s0

注：删除自建的连接connection

不使用NetworkManager管理网络

aliyun

[root@aliyun ~]# nmcli connection delete enp2s0-auto

[root@aliyun ~]# systemctl disable NetworkManager

[root@aliyun ~]# systemctl stop NetworkManager

[root@aliyun ~]# systemctl status NetworkManager

● NetworkManager.service - Network Manager

Loaded: loaded (/usr/lib/systemd/system/NetworkManager.service; disabled; vendor preset: enabled)

Active: inactive (dead)

[root@aliyun ~]# vim /etc/sysconfig/network-s/ifcfg-eth0

NAME=eth0

DEVICE=eth0

ONBOOT=yes

NETBOOT=yes

BOOTPROTO=none

IPADDR=192.168.122.169

PREFIX=24

TYPE=Ethernet

[root@aliyun ~]# systemctl restart network.service

以下配置跟NetworkManager无关：

1. 修改主机名/etc/hostname

hostnamectl set-hostname tianyun.example.com

cat /etc/hostname

reboot

2. 配置名字解析Configuring name resolution

a. hosts

[root@tianyun ~]# cat /etc/hosts

127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4

::1 localhost localhost.localdomain localhost6 localhost6.localdomain6

119.75.218.70 www.baidu.com

[root@tianyun ~]# getent hosts www.baidu.com

119.75.218.70 www.baidu.com

b. resolv.conf DNS

[root@tianyun ~]# cat /etc/resolv.conf

Generated by NetworkManager

nameserver 114.114.114.114

[root@tianyun ~]# yum -y install bind-utils

[root@tianyun ~]# host www.sina.com

www.sina.com is an alias for us.sina.com.cn.

us.sina.com.cn is an alias for wwwus.sina.com.

wwwus.sina.com has address 66.102.251.33

基本的网络测试工具

[root@tianyun ~]# ip a

[root@tianyun ~]# ip a s eth0

[root@tianyun ~]# ip route

[root@tianyun ~]# ip neigh

[root@tianyun ~]# hostname

[root@tianyun ~]# ping www.baidu.com

[root@tianyun ~]# ping -c2 www.baidu.com

[root@tianyun ~]# ip -s link show eth0

[root@tianyun ~]# traceroute www.sina.com

[root@tianyun ~]# tracepath www.sina.com

1?: [LOCALHOST] pmtu 1500

1: no reply

2: 11.245.87.126 0.787ms

3: 106.11.130.218 0.387ms

4: 42.120.244.125 0.425ms

5: 150.138.132.157 1.469ms

6: 150.138.128.241 3.546ms asymm 7

7: 202.97.40.241 24.677ms

8: 202.97.24.154 14.197ms

9: 202.97.33.154 18.340ms asymm 10

10: 202.97.90.242 182.632ms

11: 203.14.186.138 193.383ms asymm 13

12: 218.30.41.234 209.543ms asymm 13

13: 66.102.251.33 163.224ms reached

Resume: pmtu 1500 hops 13 back 14

查看设备物理连接的状态

[root@tianyun ~]# ip a

2: enp1s0: mtu 1500 qdisc pfifo_fast master br0 state DOWN qlen 1000

如果在连接禁用 ONBOOT=no 以上的信息不真实

[root@tianyun ~]# ethtool enp1s0

Link detected: no

ports and services

以下为示例服务：

[root@aliyun ~]# yum -y install httpd vsftpd

[root@aliyun ~]# systemctl start httpd

[root@aliyun ~]# systemctl start vsftpd

http 80/tcp

https 443/tcp

ssh 22/tcp

ftp 21/tcp

1. Show TCP sockets (LISTEN)

[root@aliyun ~]# ss -tnl

State Recv-Q Send-Q Local Address:Port Peer Address:Port

LISTEN 0 128 :80 :*

LISTEN 0 128 :8080 :*

LISTEN 0 10 114.215.71.214:53 :

LISTEN 0 10 10.29.89.165:53 :

LISTEN 0 10 127.0.0.1:53 :

LISTEN 0 128 :22 :*

LISTEN 0 128 127.0.0.1:953 :

LISTEN 0 128 127.0.0.1:6010 :

LISTEN 0 128 :443 :*

LISTEN 0 32 :::21 :::*

LISTEN 0 10 :::53 :::*

[root@aliyun ~]# ss -tnl |grep :80

LISTEN 0 128 :80 :*

[root@aliyun ~]# ss -tnl |grep :21

LISTEN 0 32 :::21 :::*

[root@aliyun ~]# ss -atn

State Recv-Q Send-Q Local Address:Port Peer Address:Port

LISTEN 0 128 :80 :*

LISTEN 0 10 114.215.71.214:53 :

LISTEN 0 10 10.29.89.165:53 :

LISTEN 0 10 127.0.0.1:53 :

LISTEN 0 128 :22 :*

LISTEN 0 128 127.0.0.1:953 :

LISTEN 0 128 127.0.0.1:6010 :

ESTAB 0 52 114.215.71.214:22 123.120.38.233:49603

ESTAB 0 0 114.215.71.214:40962 140.205.140.205:80

LISTEN 0 32 :::21 :::*

LISTEN 0 10 :::53 :::*

[root@aliyun ~]# ss -atn |grep :22

LISTEN 0 128 :22 :*

ESTAB 0 52 114.215.71.214:22 123.120.38.233:49603

[root@aliyun ~]# ss -atn |grep :80

LISTEN 0 128 :80 :*

ESTAB 0 0 114.215.71.214:40962 140.205.140.205:80

a 所有状态，包括 LISTEN

2. Show UDP sockets (所有状态)

[alice@tianyun ~]$ ss -anu

State Recv-Q Send-Q Local Address:Port Peer Address:Port

UNCONN 0 0 114.215.71.214:53 :

UNCONN 0 0 10.29.89.165:53 :

UNCONN 0 0 127.0.0.1:53 :

UNCONN 0 0 114.215.71.214:123 :

UNCONN 0 0 10.29.89.165:123 :

UNCONN 0 0 127.0.0.1:123 :

UNCONN 0 0 :123 :*

UNCONN 0 0 :::53 :::*

UNCONN 0 0 :::123 :::*

[kiosk@foundation0 ~]$ ss -tan |grep :5910

LISTEN 0 5 :5910 :*

ESTAB 0 0 172.25.254.250:5910 172.25.254.44:51435

ESTAB 0 0 172.25.254.250:5910 172.25.254.6:40546

ESTAB 0 0 172.25.254.250:5910 172.25.254.18:37780

ESTAB 0 0 172.25.254.250:5910 172.25.254.13:55841

ESTAB 0 0 172.25.254.250:5910 172.25.254.35:36984

ESTAB 0 0 172.25.254.250:5910 172.25.254.9:47342

ESTAB 0 0 172.25.254.250:5910 172.25.254.2:40955

ESTAB 0 0 172.25.254.250:5910 172.25.254.12:50833

ESTAB 0 0 172.25.254.250:5910 172.25.254.36:50854

ESTAB 0 0 172.25.254.250:5910 172.25.254.1:52444

ESTAB 0 0 172.25.254.250:5910 172.25.254.47:39335

ESTAB 10 0 172.25.254.250:5910 172.25.254.14:55833

临时配置网络信息

ip/netmask

ip addr add dev eth2 3.3.3.3/24

ip addr del dev eth2 3.3.3.3/24

gateway

ip route del default

ip route add default via 192.168.122.3

ip route add 10.10.10.0/24 via 192.168.122.5

hostname

hostname tianyun.cc.com

配置文件：

#vim /etc/sysconfig/network-s/ifcfg-eth0

DEVICE=eth0 设备名称

【NAME="System eth0" 设备名称】 可以不存在

BOOTPROTO=none 启动协议 获取ip地址的方式 static、none ==>静态获取 dhcp 动态

NM_CONTROLLED=no 默认是yes 关闭network-manager

ONBOOT=yes 开机启动

TYPE=Ethernet 以太网类型

HWADDR=00:0c:29:8e:a5:d3 mac地址

IPADDR=172.16.80.252 ip地址

NETMASK=255.255.0.0 掩码

PREFIX =24

NETWORK=172.16.0.0

GATEWAY=172.16.80.1 网关

dns domain name server 域名解析

帮助文档：

#vim /usr/share/doc/inits-9.03.38/sysconfig.txt

网关：网络的关卡(出口)，一般设置到路由器上

IP转发:

临时

echo 1 > /proc/sys/net/ipv4/ip_forward

永久

vim /etc/sysctl.conf 修改内核参数

net.ipv4.ip_forward = 1

sysctl -p //立即生效

dns ： 域名服务器，其中一种是解析域名到Ip地址

dns配置文件（客户端）

#vim /etc/resolv.conf

nameserver 172.16.70.250

查看mac

#arping 172.16.70.250

扫描ip

#nmap -v -sP 172.16.70.0/24

扫描端口

#nmap -v -A 172.16.70.0/24

重启网络服务:

#systemctl restart network //rhel7

#/etc/init.d/network restart //rhel5/6

#service network restart //rhel5/6