linux系统基础网络配置

时间:2023-12-19 11:58:20

1.修改主机名

临时方法:

linux系统基础网络配置

退出当前shell重新登录即可生效。此法只能临时修改生效。重启系统后失效。

提示:很多人使用hostname主机名来修改,其实这个只是作为暂时的。重启后将恢复到配置前的主机名

永久方法:

[root@greymouster ~]# hostname greymouster

linux系统基础网络配置

linux系统基础网络配置

提示:这里修改完后,执行/etc/init.d/network restart 或 source /etc/sysconfig/network等做法都不会生效,如果要单一的修改这个文件可能就需要重启服务器了

[root@greymouster ~]# reboot

重启后就永久生效了

修改 /etc/hosts 里面对应的主机名也要修改下

[root@greymouster ~]# vi /etc/hosts

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
greymouster
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6

提示:如果/etc/hosts不改,以后会遇到一些问题,如sendmail启动缓慢,ldap服务解析缓慢,sudo切用户缓慢等等都是主机名和/etc/hosts中的解析不对应导致的

2)网卡配置文件说明:

[root@greymouster ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0 #这里是网卡名称第一块网卡为eth0,第二块为eth1....
HWADDR=00:0C:29:1F:B7:7B #这里是mac地址,不同的机器不能重复,尤其是在克隆虚拟机或复制网卡配置时要注意
TYPE=Ethernet #类型
UUID=938bff60-0b1e-4ed3-9ff8-74eb8ba0ed57
ONBOOT=yes #开机网卡自启动
NM_CONTROLLED=no
DNS1:8.8.8.8 #DNS
DNS2:202.106.0.20 #DNS
BOOTPROTO=static #是否是静态的ip地址
IPADDR=192.168.1.169 #ip地址
NETMASK=255.255.255.0 #子网掩码
GATEWAY=192.168.1.1 #网关的配置,也可以命令行通过route添加删除
[root@greymouster ~]#

3)配置修改ip地址:

配置服务器ip及DNS等网络配置的方法:

直接编辑上面的配置文件

IPADDR=192.168.1.169

[root@greymouster ~]# /etc/init.d/network restart
正在关闭接口 eth0: [确定]
关闭环回接口: [确定]
弹出环回接口: [确定]
弹出界面 eth0: Determining if ip address 192.168.1.169 is already in use for device eth0...
[确定]
[root@greymouster ~]# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:0C:29:1F:B7:7B
inet addr:192.168.1.169 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe1f:b77b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:42845 errors:3 dropped:0 overruns:0 frame:0
TX packets:2711 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3406987 (3.2 MiB) TX bytes:332569 (324.7 KiB)
Interrupt:19 Base address:0x2000 [root@greymouster ~]#

ifup eth0 启动网卡

ifdown eth0 关闭网卡

临时配置两个ip 重启后会失效

[root@greymouster ~]# ifconfig eth0:0 192.168.1.168 netmask 255.255.255.0
[root@greymouster ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:1F:B7:7B
inet addr:192.168.1.169 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe1f:b77b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:43371 errors:3 dropped:0 overruns:0 frame:0
TX packets:2832 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3458368 (3.2 MiB) TX bytes:347403 (339.2 KiB)
Interrupt:19 Base address:0x2000 eth0:0 Link encap:Ethernet HWaddr 00:0C:29:1F:B7:7B
inet addr:192.168.1.168 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:19 Base address:0x2000 lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:9 errors:0 dropped:0 overruns:0 frame:0
TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:612 (612.0 b) TX bytes:612 (612.0 b) [root@greymouster ~]#

关闭临时ip:  ifconfig eth0:0 down

要想永久生效 就要复制配置文件改为eth0:0

[root@greymouster ~]# cd /etc/sysconfig/network-scripts/
[root@greymouster network-scripts]# cp ifcfg-eth0 ifcfg-eth0:0
[root@greymouster network-scripts]# vi ifcfg-eth0:0
DEVICE=eth0:0
HWADDR=00:0C:29:1F:B7:7B
TYPE=Ethernet
UUID=938bff60-0b1e-4ed3-9ff8-74eb8ba0ed57
ONBOOT=yes
NM_CONTROLLED=no
BOOTPROTO=static
IPADDR=192.168.1.168
NETMASK=255.255.255.0
GATEWAY=192.168.1.1
~
[root@greymouster network-scripts]# /etc/init.d/network restart

4)配置修改DNS:

[root@greymouster network-scripts]# cat /etc/resolv.conf
nameserver 8.8.8.8
nameserver 202.106.0.20

因为centos6.8以上 只要/etc/sysconfig/network-scripts/ifcfg-eth0 配置DNS1 重启后就会同步到 /etc/resolv.conf里面 所以在/etc/sysconfig/network-scripts/ifcfg-eth0 配置DNS一样

5)查看网关

[root@greymouster network-scripts]# route -n  查看
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 1002 0 0 eth0
0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0 eth0 #下面的命令是临时生效的
[root@greymouster network-scripts]# route del default gw 192.168.1.1 删除网关
[root@greymouster network-scripts]# route add default gw 192.168.1.1 添加网关

网关首先看/etc/sysconfig/network/ifcfg-eth0里面的GATEWAY 如果没有则找/etc/sysconfig/network下的GATEWAY

[root@greymouster ~]# cat /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=greymouster
GATEWAY=192.168.1.1
[root@greymouster ~]#

提示:如果/etc/sysconfig/network/ifcfg-eth0里面的GATEWAY配置了 则先生效

#第一生效文件
[root@greymouster ~]# grep -i gate /etc/sysconfig/network-scripts/ifcfg-eth0
GATEWAY=192.168.1.1
#第二生效文件
[root@greymouster ~]# grep -i gate /etc/sysconfig/network
GATEWAY=192.168.1.1
[root@greymouster ~]#

查看DNS域名解析

[root@greymouster ~]# dig www.baidu.com

[root@greymouster ~]# nslookup

linux 网络检查:ping

[root@greymouster ~]# traceroute www.baidu.com

windows:跟踪路由

cmd: tracert -d www.baidu.com

tcpdump 抓包:

linux系统基础网络配置

[root@greymouster ~]# host www.baidu.com
www.baidu.com is an alias for www.a.shifen.com.
www.a.shifen.com has address 119.75.217.109
www.a.shifen.com has address 119.75.218.70