Linux的网络

oracleace 2022-08-27

655

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主机名的配置

oracle@yaoyuan ~$ cat etc/hosts
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.56.107 yuan yuan.yaoyuan
oracle@yaoyuan ~$ hostname
yuan.yaoyuan
oracle@yaoyuan ~$ cat etc/hostname 
yuan.yaoyuan
oracle@yaoyuan ~$ ping yuan
PING yuan (192.168.56.107) 56(84) bytes of data.
64 bytes from yuan (192.168.56.107): icmp_seq=1 ttl=64 time=0.071 ms
64 bytes from yuan (192.168.56.107): icmp_seq=2 ttl=64 time=0.057 ms
^C
--- yuan ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1039ms
rtt min/avg/max/mdev = 0.057/0.064/0.071/0.007 ms
oracle@yaoyuan ~$ ping yuan.yaoyuan
PING yuan (192.168.56.107) 56(84) bytes of data.
64 bytes from yuan (192.168.56.107): icmp_seq=1 ttl=64 time=0.072 ms
64 bytes from yuan (192.168.56.107): icmp_seq=2 ttl=64 time=0.075 ms
^C
--- yuan ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1017ms
rtt min/avg/max/mdev = 0.072/0.073/0.075/0.008 ms

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ifconfig

ifconfig命令用于显示或设置网络设备，还可设置网络设备的状态，或是显示目前的设置。

显示网络设备信息和配置IP地址

# ifconfig 
...
# ifconfig eth0 192.168.1.56 
//给eth0网卡配置IP地址
# ifconfig eth0 192.168.1.56 netmask 255.255.255.0 
// 给eth0网卡配置IP地址,并加上子掩码
# ifconfig eth0 192.168.1.56 netmask 255.255.255.0 broadcast 192.168.1.255
// 给eth0网卡配置IP地址,加上子掩码,加上个广播地址

查看网络配置文件

oracle@yaoyuan ~$ cat etc/sysconfig/network-scripts/ifcfg-enp0s8
TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
...

配置网卡信息

配置网络服务的工作其实就是在编辑网卡配置文件

vim etc/sysconfig/network-scripts/ifcfg-ens33

➢ 设备类型：TYPE=Ethernet

➢ 地址分配模式：BOOTPROTO=static

➢ 网卡名称：NAME=eno16777736

➢ 是否启动：ONBOOT=yes

➢ IP 地址：IPADDR=192.168.10.10

➢ 子网掩码：NETMASK=255.255.255.0

➢ 网关地址：GATEWAY=192.168.10.1

➢ DNS 地址：DNS1=192.168.10.1

修改了网络配置后，重新启动网络服务：systemctl restart network

关注ONBOOT、IPADDR等

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nmtui工具

文本方式的配置网络界面

配置完成后重新启动网络：systemctl restart network

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ip工具

ip命令也可以用于配置ip地址和激活网卡

# ip addr
...
# ip --help
...ethtool

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ethtool工具

ethtool 是用于查询及设置网卡参数的命令。

ethtool ethx 查询ethx网口基本设置，其中 x 是对应网卡的编号，如eth0、eth1等等

oracle@yaoyuan ~$ ethtool em1 
Settings for em1:
  Supported ports: [ TP ]
  Supported link modes:   10baseT/Half 10baseT/Full 
                          100baseT/Half 100baseT/Full 
                          1000baseT/Half 1000baseT/Full 
  Supported pause frame use: No
  Supports auto-negotiation: Yes
  Supported FEC modes: Not reported
  Advertised link modes:  10baseT/Half 10baseT/Full 
                          100baseT/Half 100baseT/Full 
                          1000baseT/Half 1000baseT/Full 
  Advertised pause frame use: Symmetric
  Advertised auto-negotiation: Yes
  Advertised FEC modes: Not reported
  Link partner advertised link modes:  10baseT/Half 10baseT/Full 
                                       100baseT/Half 100baseT/Full 
                                       1000baseT/Full 
  Link partner advertised pause frame use: No
  Link partner advertised auto-negotiation: Yes
  Link partner advertised FEC modes: Not reported
  Speed: 1000Mb/s
  Duplex: Full
  Port: Twisted Pair
  PHYAD: 1
  Transceiver: internal
  Auto-negotiation: on
  MDI-X: off
Cannot get wake-on-lan settings: Operation not permitted
  Current message level: 0x000000ff (255)
             drv probe link timer ifdown ifup rx_err tx_err
  Link detected: yes
oracle@yaoyuan ~$ ethtool p5p1
Settings for p5p1:
  Supported ports: [ FIBRE ]
  Supported link modes:   1000baseT/Full 
                          10000baseT/Full 
  Supported pause frame use: Symmetric
  Supports auto-negotiation: Yes
  Supported FEC modes: Not reported
  Advertised link modes:  1000baseT/Full 
                          10000baseT/Full 
  Advertised pause frame use: Symmetric
  Advertised auto-negotiation: Yes
  Advertised FEC modes: Not reported
  Speed: 10000Mb/s
  Duplex: Full
  Port: FIBRE
  PHYAD: 0
  Transceiver: internal
  Auto-negotiation: on
Cannot get wake-on-lan settings: Operation not permitted
  Current message level: 0x00000007 (7)
             drv probe link
  Link detected: yes

关注Link detected是否接网线，Speed速度：千兆网或者万兆网。上面两个例子第一个是千兆网第二个是万兆网

当服务器有多个网卡并且已经配置好运行当中，你却没记得eth0、eth1、eth2.....分别对应的是哪个物理的网卡，此时可以使用如下命令：

ethtool -p eth0

此时就会看到 eth0 对应的物理口一个灯在不停地闪烁，对了。这就是我们在系统看到的那个叫eth0的网卡了，就是这么简单。按ctrl+ c停止。

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ping和telnet工具

测试到一个远端的ip通或者不同通常用ping，测试端口用telnet。

oracle@yaoyuan ~$ ping 192.168.56.107
PING 192.168.56.107 (192.168.56.107) 56(84) bytes of data.
64 bytes from 192.168.56.107: icmp_seq=1 ttl=64 time=0.072 ms
64 bytes from 192.168.56.107: icmp_seq=2 ttl=64 time=0.038 ms
^C
--- 192.168.56.107 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1002ms
rtt min/avg/max/mdev = 0.038/0.055/0.072/0.017 ms
oracle@yaoyuan ~$ telnet 192.168.56.107 1521
Trying 192.168.56.107...
Connected to 192.168.56.107.