CentOS 7网络属性配置
时间:2016-05-23 20:59 来源:未知 作者:IT
一、简单介绍
在CentOS 7中对网络管理还是有不少变化的，例如管理服务的命令变为systemctl，许多命令可以更改后直接生效，还有许多独有的工具，本文以CentOS 6与CentOS 7对比进行讲解，下面现总体介绍一下网络属性配置工具。
ifcfg家族
ifcofnig：配置IP，NETMASK
route：路由
netstat：状态及统计数据查看
iproute家族
ip OBJECT：
addr： 地址和掩码
link：接口
route：路由
ss：状态及统计数据查看
CentOS 7：nm（Network Manager）家族
nmcli：命令行工具
nmtui：text window工具
二、ifcfg家族配置管理
1、ifconfig命令：配置网络接口（configure a network interface）
查看网络配置：ifconfig [-a] [interface]
-a：查看当前系统上所有网络接口的状态及详细信息，包括inactive状态的接口
# ifconfig
eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.18.250.108 netmask 255.255.0.0 broadcast 172.18.255.255
inet6 fe80::20c:29ff:fedd:c19c prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:dd:c1:9c txqueuelen 1000 (Ethernet)
RX packets 267796 bytes 27852817 (26.5 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 4268 bytes 556507 (543.4 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 0 (Local Loopback)
RX packets 56 bytes 4760 (4.6 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 56 bytes 4760 (4.6 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
CentOS 7：ifconfig命令显示参数详解
eno1677736:网卡名称
inet：ip地址
netmask：子网掩码
broadcast：广播地址
UP：网卡表示激活状态
BROADCAST：支持广播功能
MULTICAST：支持组播功能
RUNNING：处于运行状态
mtu：网卡的最大传输单元
inet6：表示IPV6地址
ether：以太网地址，表示mac地址
txqueuelen：传输队列长度
RX packets 267796 bytes 27852817 (26.5 MiB)：接收到报文的数量，后面表示接 收到所有报文的大小
RX errors：接收到错误报文的个数
dropped：丢包的数量
overruns：溢出的
TX packets 4268 bytes 556507 (543.4 KiB)：传出到报文的数量，后面表示传出所 有报文的大小
TX errors：传出报文的错误数量
dropped：发送出去丢包数量
此处为CentOS 6上使用ifconfig的显示（注意：不标明的都默认指CentOS7，当与CentOS不同时会标注）
# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:69:45:7B
inet addr:172.18.251.87 Bcast:172.18.255.255 Mask:255.255.0.0
inet6 addr: fe80::20c:29ff:fe69:457b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:303612 errors:0 dropped:0 overruns:0 frame:0
TX packets:2296 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:31934172 (30.4 MiB) TX bytes:261862 (255.7 KiB)
eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85
inet addr:192.168.200.3 Bcast:192.168.200.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe69:4585/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:292609 errors:0 dropped:0 overruns:0 frame:0
TX packets:202 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:30767674 (29.3 MiB) TX bytes:26126 (25.5 KiB)
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:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
CentOS 6：ifconfig命令显示参数详解
eth0:网卡名称
Link encap：接口类型
inet addr：ip地址
Bcast：广播地址
Mask：子网掩码
inet6 addr：IPV6地址
UP：网卡表示激活状态
BROADCAST：支持广播功能
MULTICAST：支持组播功能
RUNNING：处于运行状态
mtu：网卡的最大传输单元
ether：以太网地址，表示mac地址
txqueuelen：传输队列长度
RX packets 接收到报文的数量
errors：接收到错误报文的个数
dropped：丢包的数量
overruns：溢出的
TX packets 传出到报文的数量
errors：传出报文的错误数量
dropped：丢包的数量
overruns：溢出的
RX bytes: 接收到报文的总大小
TX bytes: 传输报文的总大小
# ifconfig -a
eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.18.250.108 netmask 255.255.0.0 broadcast 172.18.255.255
inet6 fe80::20c:29ff:fedd:c19c prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:dd:c1:9c txqueuelen 1000 (Ethernet)
RX packets 267877 bytes 27861934 (26.5 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 4283 bytes 559025 (545.9 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
eno33554984: flags=4098<BROADCAST,MULTICAST> mtu 1500
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
RX packets 257603 bytes 26825123 (25.5 MiB)
RX errors 0 dropped 269 overruns 0 frame 0
TX packets 38 bytes 3900 (3.8 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 0 (Local Loopback)
RX packets 56 bytes 4760 (4.6 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 56 bytes 4760 (4.6 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
可以指定接口名称，进行单独查看
# ifconfig eno33554984
eno33554984: flags=4098<BROADCAST,MULTICAST> mtu 1500
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
RX packets 257603 bytes 26825123 (25.5 MiB)
RX errors 0 dropped 269 overruns 0 frame 0
TX packets 38 bytes 3900 (3.8 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
修改网络配置：ifconfig [-v] interface [aftype] options | address …
方式一：
# ifconfig eno33554984 192.168.200.5/24 up
# ifconfig eno33554984
eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.200.5 netmask 255.255.255.0 broadcast 192.168.200.255
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
RX packets 259004 bytes 26985088 (25.7 MiB)
RX errors 0 dropped 271 overruns 0 frame 0
TX packets 40 bytes 4020 (3.9 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
# 注意此配置仅限临时生效，重启网络服务或者重启系统，内核会重读配置文件，将配置文件中的参数在执行一遍.
方式二：
# ifconfig eno33554984 192.168.100.5 netmask 255.255.255.0 up
# ifconfig eno33554984
eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.100.5 netmask 255.255.255.0 broadcast 192.168.100.255
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
RX packets 260398 bytes 27138591 (25.8 MiB)
RX errors 0 dropped 273 overruns 0 frame 0
TX packets 40 bytes 4020 (3.9 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
2、route命令：查看及管理路由（route – show / manipulate the IP routing table）
命令格式：route add [-net|-host] target [netmask Nm] [gw GW] [[dev] If]
-net：表示添加网络路由
-host：表示添加主机路由
gw：为默认网关
查看：
route -n
# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736
172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736
192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984
添加路由：
# route add -net 10.0.0.0/8 gw 192.168.100.5 dev eno33554984
# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736
10.0.0.0 192.168.100.5 255.0.0.0 UG 0 0 0 eno33554984
172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736
192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984
删除路由：
# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736
10.0.0.0 192.168.100.5 255.0.0.0 UG 0 0 0 eno33554984
172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736
192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984
# route del -net 10.0.0.0/8
# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736
172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736
192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984
3、netstat命令：打印网络连接，路由表，接口等信息（Print network connections, routing tables, interface statis﹖ics, masquerade connections, and multicast memberships）
显示网络连接：
netstat [–tcp|-t] [–udp|-u] [–udplite|-U] [–sctp|-S] [–raw|-w] [–listening|-l] [–all|-a] [–numeric|-n] [–extend|-e[–extend|-e]] [–program|-p]
-t：TCP协议的相关连接，连接均有其状态
-u：UDP协议相关的连接
-w：raw socket相关的；连接
-l：处于监听状态的连接
-a：所有状态
-n：以数字格式显示IP和Port
-e：扩展格式
-p：显示相关的进程及PID
# 常用组合：
-tan，-una，-tnl，-unl，-tunlp，-antup
# netstat -tan
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:6010 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:6011 0.0.0.0:* LISTEN
tcp 0 52 172.18.250.108:22 172.18.4.1:49701 ESTABLISHED
tcp 0 0 172.18.250.108:22 172.18.4.1:49924 ESTABLISHED
tcp6 0 0 :::22 :::* LISTEN
tcp6 0 0 ::1:631 :::* LISTEN
tcp6 0 0 ::1:25 :::* LISTEN
tcp6 0 0 ::1:6010 :::* LISTEN
tcp6 0 0 ::1:6011 :::* LISTEN
# netstat -uan
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
udp 0 0 0.0.0.0:10042 0.0.0.0:*
udp 0 0 127.0.0.1:323 0.0.0.0:*
udp 0 0 0.0.0.0:68 0.0.0.0:*
udp6 0 0 ::1:323 :::*
udp6 0 0 :::50626 :::*
# netstat -tunlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1054/sshd
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 1052/cupsd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1143/master
tcp 0 0 127.0.0.1:6010 0.0.0.0:* LISTEN 1190/sshd: root@pts
tcp 0 0 127.0.0.1:6011 0.0.0.0:* LISTEN 5116/sshd: root@pts
tcp6 0 0 :::22 :::* LISTEN 1054/sshd
tcp6 0 0 ::1:631 :::* LISTEN 1052/cupsd
tcp6 0 0 ::1:25 :::* LISTEN 1143/master
tcp6 0 0 ::1:6010 :::* LISTEN 1190/sshd: root@pts
tcp6 0 0 ::1:6011 :::* LISTEN 5116/sshd: root@pts
udp 0 0 0.0.0.0:10042 0.0.0.0:* 4399/dhclient
udp 0 0 127.0.0.1:323 0.0.0.0:* 752/chronyd
udp 0 0 0.0.0.0:68 0.0.0.0:* 4399/dhclient
udp6 0 0 ::1:323 :::* 752/chronyd
udp6 0 0 :::50626 :::* 4399/dhclient
# netstat -antup
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1054/sshd
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 1052/cupsd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1143/master
tcp 0 0 127.0.0.1:6010 0.0.0.0:* LISTEN 1190/sshd: root@pts
tcp 0 0 127.0.0.1:6011 0.0.0.0:* LISTEN 5116/sshd: root@pts
tcp 0 52 172.18.250.108:22 172.18.4.1:49701 ESTABLISHED 1190/sshd: root@pts
tcp 0 0 172.18.250.108:22 172.18.4.1:49924 ESTABLISHED 5116/sshd: root@pts
tcp6 0 0 :::22 :::* LISTEN 1054/sshd
tcp6 0 0 ::1:631 :::* LISTEN 1052/cupsd
tcp6 0 0 ::1:25 :::* LISTEN 1143/master
tcp6 0 0 ::1:6010 :::* LISTEN 1190/sshd: root@pts
tcp6 0 0 ::1:6011 :::* LISTEN 5116/sshd: root@pts
udp 0 0 0.0.0.0:10042 0.0.0.0:* 4399/dhclient
udp 0 0 127.0.0.1:323 0.0.0.0:* 752/chronyd
udp 0 0 0.0.0.0:68 0.0.0.0:* 4399/dhclient
udp6 0 0 ::1:323 :::* 752/chronyd
udp6 0 0 :::50626 :::* 4399/dhclient
显示路由表：netstat -rn
-r：显示内核路由表
-n：数字格式显示
# netstat -rn
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 172.18.0.1 0.0.0.0 UG 0 0 0 eno16777736
10.0.0.0 192.168.100.5 255.0.0.0 UG 0 0 0 eno33554984
172.18.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eno16777736
192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984
显示借口的统计数据：
netstat {–interfaces|-I|-i} [iface] [–all|-a] [–extend|-e] [–verbose|-v] [–program|-p] [–numeric|-n]
所有接口：
netstat -i
# netstat -i
Kernel Interface table
Iface MTU RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg
eno16777 1500 295676 0 0 0 5992 0 0 0 BMRU
eno33554 1500 281789 0 313 0 40 0 0 0 BMRU
lo 65536 60 0 0 0 60 0 0 0 LRU
具体值：
Iface：借口
MTU：最大传输单元
RX-OK：成功接收报文的数量
RX-ERR：失败的传输报文的数量
RX-DRP：接收丢弃的报文数量
RX-OVR：接收溢出的报文数量
TX-OK：成功传输报文的数量
TX-ERR：失败的传输报文的数量
TX-DRP：传出丢弃的传输数量
TX-OVR：传出溢出的传输数量
Flg：标志
4、ifup/ifdown命令：
# 注意：通过配置文件/etc/sysconfig/network-scripts/ifcfg-IFACE来识别接口并完成配置
# 此处在显示上CentOS 6与CentOS 7有所不同
CentOS 6： 在使用ifdown命令时，禁用的接口用ifconfig命令显示不出来，且在显示中也没有UP选项，如需显示需要指定接口或者使用-a选项
# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:69:45:7B
inet addr:172.18.251.87 Bcast:172.18.255.255 Mask:255.255.0.0
inet6 addr: fe80::20c:29ff:fe69:457b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:320170 errors:0 dropped:0 overruns:0 frame:0
TX packets:2653 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:33769657 (32.2 MiB) TX bytes:313476 (306.1 KiB)
eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85
inet addr:192.168.200.3 Bcast:192.168.200.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe69:4585/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:306513 errors:0 dropped:0 overruns:0 frame:0
TX packets:218 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:32321812 (30.8 MiB) TX bytes:27212 (26.5 KiB)
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:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
# ifdown eth1
# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0C:29:69:45:7B
inet addr:172.18.251.87 Bcast:172.18.255.255 Mask:255.255.0.0
inet6 addr: fe80::20c:29ff:fe69:457b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:319600 errors:0 dropped:0 overruns:0 frame:0
TX packets:2601 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:33705819 (32.1 MiB) TX bytes:305610 (298.4 KiB)
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:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
# ifconfig eth1
eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:306469 errors:0 dropped:0 overruns:0 frame:0
TX packets:211 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:32316117 (30.8 MiB) TX bytes:26744 (26.1 KiB)
# ifup eth1
Determining if ip address 192.168.200.3 is already in use for device eth1...
# ifconfig eth1
eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85
inet addr:192.168.200.3 Bcast:192.168.200.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fe69:4585/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:308152 errors:0 dropped:0 overruns:0 frame:0
TX packets:230 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:32503780 (30.9 MiB) TX bytes:28040 (27.3 KiB)
CentOS 7：在CentOS 7 上用ifdown命令禁用网卡UP选项不会消失，但是IP没有显示，此处与CentOS 6相同
# ifconfig eno33554984
eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.100.3 netmask 255.255.255.0 broadcast 192.168.100.255
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
RX packets 313238 bytes 33067566 (31.5 MiB)
RX errors 0 dropped 349 overruns 0 frame 0
TX packets 42 bytes 4140 (4.0 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
# ifdown eno33554984
Device 'eno33554984' successfully disconnected.
# ifconfig
eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.18.250.108 netmask 255.255.0.0 broadcast 172.18.255.255
inet6 fe80::20c:29ff:fedd:c19c prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:dd:c1:9c txqueuelen 1000 (Ethernet)
RX packets 327832 bytes 34538419 (32.9 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 6428 bytes 919810 (898.2 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
RX packets 313451 bytes 33089849 (31.5 MiB)
RX errors 0 dropped 349 overruns 0 frame 0
TX packets 42 bytes 4140 (4.0 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 0 (Local Loopback)
RX packets 64 bytes 5440 (5.3 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 64 bytes 5440 (5.3 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
# ifup eno33554984
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/12)
# ifconfig eno33554984
eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.100.3 netmask 255.255.255.0 broadcast 192.168.100.255
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
RX packets 314723 bytes 33233696 (31.6 MiB)
RX errors 0 dropped 349 overruns 0 frame 0
TX packets 44 bytes 4260 (4.1 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
5、配置主机名：
hostname命令：
查看：hostname
配置：hostname HOSTNAME
当前系统有效，重启后无效
# hostname
centos6.7
# hostname myserver
# hostname
myserver
hostnamectl命令（CentOS 7）：
hostnamectl status：显示当前主机名信息
hostnamectl set-hostname：设定主机名，永久有效
# hostnamectl status
Static hostname: centos7
Icon name: computer-vm
Chassis: vm
Machine ID: 94b3ec34f75d44df93cc011c79159864
Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7
Virtualization: vmware
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-327.el7.x86_64
Architecture: x86-64
# hostnamectl set-hostname centos7.2
# hostnamectl status
Static hostname: centos7.2
Icon name: computer-vm
Chassis: vm
Machine ID: 94b3ec34f75d44df93cc011c79159864
Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7
Virtualization: vmware
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-327.el7.x86_64
Architecture: x86-64
# 注意hostname在Centos 7上面也可以使用，但是设置后显示临时主机名
例：
# hostnamectl status
Static hostname: centos7.2
Icon name: computer-vm
Chassis: vm
Machine ID: 94b3ec34f75d44df93cc011c79159864
Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7
Virtualization: vmware
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-327.el7.x86_64
Architecture: x86-64
# hostname centos777
# hostnamectl status
Static hostname: centos7.2
Transient hostname: hello
Icon name: computer-vm
Chassis: vm
Machine ID: 94b3ec34f75d44df93cc011c79159864
Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7
Virtualization: vmware
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-327.el7.x86_64
Architecture: x86-64
# hostname
centos777
配置文件：
CentOS6：/etc/sysconfig/network
HOSTNAME=<HOSTNAME>
# hostname
myserver
# vim /etc/sysconfig/network
# cat /etc/sysconfig/network
NETWORKING=yes
HOSTNAME=mycentos6
# hostname
myserver
CentOS7：/etc/hostname
HOSTNAME
# hostnamectl status
Static hostname: centos7
Icon name: computer-vm
Chassis: vm
Machine ID: 94b3ec34f75d44df93cc011c79159864
Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7
Virtualization: vmware
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-327.el7.x86_64
Architecture: x86-64
# vim /etc/hostname
# cat /etc/hostname
mycentos7
# hostnamectl status
Static hostname: centos7
Icon name: computer-vm
Chassis: vm
Machine ID: 94b3ec34f75d44df93cc011c79159864
Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7
Virtualization: vmware
Operating System: CentOS Linux 7 (Core)
CPE OS Name: cpe:/o:centos:centos:7
Kernel: Linux 3.10.0-327.el7.x86_64
Architecture: x86-64
# 注意：在CentOS 6中此方法不会立即生效，但是在CentOS 7中会立即生效
6、配置DNS服务器指向：
配置文件：/etc/resolv.conf
nameserverDNS_SERVER_IP
如何测试（host/nslookup/dig）:
# dig -t A FQDN
FQDN –> IP
# dig -x IP
IP –> FQDN
# dig 命令的好处在于，他不检查hosts文件中的定义，直接去dns服务器解析
三、iproute家族配置管理
1、ip命令
show / manipulate routing, devices, policy routing and tunnels
查看和配置 路由表、设备、策略路由等
ip [ OPTIONS ] OBJECT { COMMAND | help }
OBJECT := { link | addr | route | netns }
a、ip link
网络设备配置（network device configuration）
1、 ip link set：改变设备属性
（1）dev NAME (default)：指明要管理的设备，dev关键字可省略；
（2）up和down：
# ip link set eno33554984 down
# ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff
3: eno33554984: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
# ip link set eno33554984 up
# ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
（3）multicast on或multicast off：启用或禁用多播功能；
# 关闭后可以看到没有UP选项，表示此网卡已关闭
（4）name NAME：重命名接口
# ip link set eno33554984 down
# ip link set eno33554984 name eno666777888
# ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff
3: eno666777888: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
# 改名时需要关闭网卡设备
（5）mtu NUMBER：设置MTU的大小，默认为1500；
# ip link set eno666777888 mtu 1000
# ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff
3: eno666777888: <BROADCAST,MULTICAST> mtu 1000 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
（6）netns PID：ns为namespace，用于将接口移动到指定的网络名称空间；（在后面会详细讲解）
2、ip link show：列出设备属性
# ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff
3: eno666777888: <BROADCAST,MULTICAST> mtu 1000 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
# ip link show eno666777888
3: eno666777888: <BROADCAST,MULTICAST> mtu 1000 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
3、 ip link help：显示简要使用帮助
b、ip netns # 注意：此命令仅在CentOS 7中支持
管理网络名称空间（manage network namespaces）
ip netns list：列出所有的netns
# ip netns list
myspace
ip netns add NAME：创建指定的netns
# ip netns add space1
# ip netns list
space1
myspace
ip netns del NAME：删除指定的netns
# ip netns del myspace
# ip netns list
space1
ip netns exec NAME COMMAND：在指定的netns中运行命令
# ip link set eno666777888 netns space1
# ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff
# 加入名称空间后 使用ip link show查看，可以看到此处看不到了eno66677788
# ip netns exec space1 ip link show
1: lo: <LOOPBACK> mtu 65536 qdisc noop state DOWN mode DEFAULT
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
3: eno666777888: <BROADCAST,MULTICAST> mtu 1000 qdisc noop state DOWN mode DEFAULT qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
# 使用此命令可以查看名称空间space1中的网卡设备
c、ip address
协议地址管理（protocol address management）
ip address add：添加新的协议地址
[label NAME]：为额外添加的地址指明接口别名
# ip add add label eno33554984:0 10.0.0.100/8 dev eno33554984
# ifconfig
eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.18.250.108 netmask 255.255.0.0 broadcast 172.18.255.255
inet6 fe80::20c:29ff:fedd:c19c prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:dd:c1:9c txqueuelen 1000 (Ethernet)
RX packets 372250 bytes 39402750 (37.5 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 9582 bytes 1347144 (1.2 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1000
inet 192.168.200.2 netmask 255.255.255.0 broadcast 0.0.0.0
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
RX packets 344492 bytes 36539558 (34.8 MiB)
RX errors 0 dropped 365 overruns 0 frame 0
TX packets 48 bytes 4500 (4.3 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
eno33554984:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1000
inet 10.0.0.100 netmask 255.0.0.0 broadcast 0.0.0.0
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 0 (Local Loopback)
RX packets 76 bytes 6460 (6.3 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 76 bytes 6460 (6.3 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
[broadcast ADDRESS]：广播地址；会根据IP和NETMASK自动计算得到
[scope SCOPE_VALUE]：作用域，默认设置为global
global：全局可用；
link：接口可用；
host：仅本机可用；
# ip addr show eno33554984
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
inet 192.168.200.2/24 scope global eno33554984
valid_lft forever preferred_lft forever
inet 10.0.0.100/8 scope global eno33554984:0
valid_lft forever preferred_lft forever
inet 10.0.0.200/8 scope global secondary eno33554984
valid_lft forever preferred_lft forever
ip address delete：删除协议地址
# ip addr show eno33554984
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
inet 192.168.200.2/24 scope global eno33554984
valid_lft forever preferred_lft forever
inet 10.0.0.100/8 scope global eno33554984:0
valid_lft forever preferred_lft forever
inet 10.0.0.200/8 scope global secondary eno33554984
valid_lft forever preferred_lft forever
# ip add del 192.168.200.2/24 dev eno33554984
# ip addr show eno33554984
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
inet 10.0.0.100/8 scope global eno33554984:0
valid_lft forever preferred_lft forever
inet 10.0.0.200/8 scope global secondary eno33554984
valid_lft forever preferred_lft forever
ip address show：查看协议地址
# ip add show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
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: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff
inet 172.18.250.108/16 brd 172.18.255.255 scope global dynamic eno16777736
valid_lft 63185sec preferred_lft 63185sec
inet6 fe80::20c:29ff:fedd:c19c/64 scope link
valid_lft forever preferred_lft forever
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
inet 10.0.0.100/8 scope global eno33554984:0
valid_lft forever preferred_lft forever
inet 10.0.0.200/8 scope global secondary eno33554984
valid_lft forever preferred_lft forever
ip address flush：清除协议地址（清除某设备上的所有地址）
# ip add show eno33554984
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
inet 10.0.0.100/8 scope global eno33554984:0
valid_lft forever preferred_lft forever
inet 10.0.0.200/8 scope global secondary eno33554984
valid_lft forever preferred_lft forever
# ip add flush dev eno33554984
# ip add show eno33554984
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
d、ip route
路由表管理（routing table management）
ip route add：添加新的路由
# ip route add 20.0.0.0/8 via 10.0.0.20 dev eno33554984
# ip route show
default via 172.18.0.1 dev eno16777736 proto static metric 100
10.0.0.0/8 dev eno33554984 proto kernel scope link src 10.0.0.200
20.0.0.0/8 via 10.0.0.20 dev eno33554984
172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100
192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2
192.168.100.0/24 dev eno33554984 proto kernel scope link src 192.168.100.2
ip route change：修改路由
# ip route change 20.0.0.0/8 via 172.18.250.108 dev eno16777736
# ip route show
default via 172.18.0.1 dev eno16777736 proto static metric 100
10.0.0.0/8 dev eno33554984 proto kernel scope link src 10.0.0.200
20.0.0.0/8 via 172.18.250.108 dev eno16777736
172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100
192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2
192.168.100.0/24 dev eno33554984 proto kernel scope link src 192.168.100.2
ip route replace：改变或者添加新的路由（表示如果没有就新添加）
ip route add TYPE PREFIX via GW [dev IFACE] [src SOURCE_IP]
ip route delete：删除路由
# ip route show
default via 172.18.0.1 dev eno16777736 proto static metric 100
10.0.0.0/8 dev eno33554984 proto kernel scope link src 10.0.0.200
20.0.0.0/8 via 172.18.250.108 dev eno16777736
172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100
192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2
192.168.100.0/24 dev eno33554984 proto kernel scope link src 192.168.100.2
# ip route del 10.0.0.0/8
# ip route show
default via 172.18.0.1 dev eno16777736 proto static metric 100
20.0.0.0/8 via 172.18.250.108 dev eno16777736
172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100
192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2
192.168.100.0/24 dev eno33554984 proto kernel scope link src 192.168.100.2
ip route show：查看路由
ip route flush：删除路由表
# ip route flush 192.168.100/24
# ip route show
default via 172.18.0.1 dev eno16777736 proto static metric 100
20.0.0.0/8 via 172.18.250.108 dev eno16777736
172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100
192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2
ip route get：查看一条路由
# ip route get 20.0.0.0/8
20.0.0.0 dev eno16777736 src 172.18.250.108
cache
2、ss命令
另一个套接字管理程序（another utility to investigate sockets）
ss [options] [FILTER]
选项：
-t：TCP协议的相关连接
-u：UDP相关的连接
-w：raw socket相关的连接
-l：监听状态的连接
-a：所有状态的连接
-n：数字格式
-p：相关的程序及其PID
-e：扩展格式信息
-m：内存用量
-o：计时器信息
# 用法与netstat相同，组合方式也可以参照netstat
常用组合：-tan，-una，-tnl，-unl，-tunlp，-antup
# ss -tan
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:22 *:*
LISTEN 0 128 127.0.0.1:631 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 128 127.0.0.1:6010 *:*
LISTEN 0 128 127.0.0.1:6011 *:*
ESTAB 0 52 172.18.250.108:22 172.18.4.1:49701
ESTAB 0 0 172.18.250.108:22 172.18.4.1:49924
LISTEN 0 128 :::22 :::*
LISTEN 0 128 ::1:631 :::*
LISTEN 0 100 ::1:25 :::*
LISTEN 0 128 ::1:6010 :::*
LISTEN 0 128 ::1:6011 :::*
# ss -uan
State Recv-Q Send-Q Local Address:Port Peer Address:Port
UNCONN 0 0 *:10042 *:*
UNCONN 0 0 127.0.0.1:323 *:*
UNCONN 0 0 *:68 *:*
UNCONN 0 0 ::1:323 :::*
UNCONN 0 0 :::50626 :::*
FILTER := [ state TCP-STATE ] [ EXPRESSION ]
[EXPRESSION]
dport =
sport =
# ss -tan '( dport = 22 or sport = 22 )'
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:22 *:*
ESTAB 0 52 172.18.250.108:22 172.18.4.1:49701
ESTAB 0 0 172.18.250.108:22 172.18.4.1:49924
LISTEN 0 128 :::22 :::*
四、管理网络属性之配置文件
IP/NETMASK/GW/DNS等配置文件：/etc/sysconfig/network-scripts/ifcfg-IFACE
路由相关的配置文件：/etc/sysconfig/networkj-scripts/route-IFACE
命令方式修改：
CentOS 6：system-config-network
setup
CentOS 7：nmtui
ifcfg-IFACE文件中的参数：
DEVICE：此配置文件对应的设备的名称；
ONBOOT：在系统引导过程中，是否激活此接口；
UUID：此设备的惟一标识；
IPV6INIT：是否初始化IPv6；
BOOTPROTO：激活此接口时使用什么协议来配置接口属性，常用的有dhcp、bootp、static、none；
TYPE：接口类型，常见的有Ethernet, Bridge；
DNS1：第一DNS服务器指向；
DNS2：备用DNS服务器指向；
DOMAIN：DNS搜索域；
IPADDR： IP地址；
NETMASK：子网掩码；CentOS 7支持使用PREFIX以长度方式指明子网掩码；
GATEWAY：默认网关；
USERCTL：是否允许普通用户控制此设备；
PEERDNS：如果BOOTPROTO的值为“dhcp”，是否允许dhcp_server分配的dns服务器指向覆盖本地手动指定的DNS服务器指向；默认为允许；
HWADDR：设备的MAC地址；
NM_CONTROLLED：是否使用NetworkManager服务来控制接口；
示例：
CentOS 7：
IPV6INIT=yes
BOOTPROTO=none
DEVICE=eno16777736
ONBOOT=yes
UUID=fc03aa9a-32b4-4d25-9576-288a0e3cd39a
TYPE=Ethernet
DEFROUTE=yes
NAME="System eno16777736"
PEERDNS=yes
IPADDR=172.18.4.1
PREFIX=8
GATEWAY=172.18.0.1
DNS1=202.106.0.20
DNS2=172.18.0.1
CentOS 6：
DEVICE=eth0
HWADDR=00:0C:29:69:45:7B
TYPE=Ethernet
UUID=1e9d304f-319a-4467-ac3c-67159f182f33
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=dhcp
网络服务：
network
NetworkManger
管理网络服务：
CentOS 6: service {network|NetworkManager} {start|stop|restart|status}
# cat /etc/sysconfig/network-scripts/ifcfg-eth1
DEVICE=eth1
TYPE=Ethernet
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=none
IPADDR=10.0.0.100
PREFIX=8
GATEWAY=10.0.0.1
DNS1=202.106.0.20
# service network restart
Shutting down interface eth0: [ OK ]
Shutting down interface eth1: [ OK ]
Shutting down loopback interface: [ OK ]
Bringing up loopback interface: [ OK ]
Bringing up interface eth0:
Determining IP information for eth0... done.
[ OK ]
Bringing up interface eth1: Determining ip address 10.0.0.100 is already in use for device eth1.. [ OK ]
# ifconfig eth1
eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85
inet addr:10.0.0.100 Bcast:10.255.255.255 Mask:255.0.0.0
inet6 addr: fe80::20c:29ff:fe69:4585/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:411362 errors:0 dropped:0 overruns:0 frame:0
TX packets:240 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:44602847 (42.5 MiB) TX bytes:28728 (28.0 KiB)
CentOS 7: systemctl {start|stop|restart|status} {network|NetworkManager}.service
# cat /etc/sysconfig/network-scripts/ifcfg-eno33554984
# Generated by parse-kickstart
BOOTPROTO=none
DEVICE=eno33554984
ONBOOT=yes
TYPE=Ethernet
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
NAME="System eno33554984"
PEERDNS=yes
PEERROUTES=yes
IPADDR=20.0.0.100
PREFIX=24
GATEWAY=20.0.0.1
DNS1=202.106.0.20
# systemctl restart network.service
# ifconfig eno33554984
eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1000
inet 20.0.0.100 netmask 255.255.255.0 broadcast 20.0.0.255
ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet)
RX packets 406943 bytes 44125370 (42.0 MiB)
RX errors 0 dropped 635 overruns 0 frame 0
TX packets 50 bytes 4620 (4.5 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
配置文件配置路由：/etc/sysconfig/network-scripts/route-IFACE
支持两种配置方式，但不可混用；
(1) 每行一个路由条目：
TARGET via GW
# cat /etc/sysconfig/network-scripts/route-eno33554984
172.0.0.0/8 via 20.0.0.100
# systemctl restart network.service
# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736
0.0.0.0 20.0.0.1 0.0.0.0 UG 101 0 0 eno33554984
20.0.0.0 0.0.0.0 255.255.255.0 U 100 0 0 eno33554984
172.0.0.0 20.0.0.100 255.0.0.0 UG 100 0 0 eno33554984
172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736
(2) 每三行一个路由条目：
ADDRESS#=TARGET
NETMASK#=MASK
GATEWAY#=NEXTHOP
# cat /etc/sysconfig/network-scripts/route-eno33554984
ADDRESS0=11.0.0.0
NETMASK0=255.0.0.0
GATEWAY0=20.0.0.100
# systemctl restart network.service
# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736
0.0.0.0 20.0.0.1 0.0.0.0 UG 101 0 0 eno33554984
11.0.0.0 20.0.0.100 255.0.0.0 UG 100 0 0 eno33554984
20.0.0.0 0.0.0.0 255.255.255.0 U 100 0 0 eno33554984
172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736
对于CentOS 7的网络属性管理就写到这里了，感觉写的不错可以给点个赞。
作者： Ace QQ1257465991 Linux运维攻城狮一只
Q/A：如有问题请慷慨提出
(责任编辑：IT)
一、简单介绍 在CentOS 7中对网络管理还是有不少变化的，例如管理服务的命令变为systemctl，许多命令可以更改后直接生效，还有许多独有的工具，本文以CentOS 6与CentOS 7对比进行讲解，下面现总体介绍一下网络属性配置工具。 ifcfg家族 ifcofnig：配置IP，NETMASK route：路由 netstat：状态及统计数据查看 iproute家族 ip OBJECT： addr： 地址和掩码 link：接口 route：路由 ss：状态及统计数据查看 CentOS 7：nm（Network Manager）家族 nmcli：命令行工具 nmtui：text window工具 二、ifcfg家族配置管理 1、ifconfig命令：配置网络接口（configure a network interface）查看网络配置：ifconfig [-a] [interface] -a：查看当前系统上所有网络接口的状态及详细信息，包括inactive状态的接口 # ifconfig eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 172.18.250.108 netmask 255.255.0.0 broadcast 172.18.255.255 inet6 fe80::20c:29ff:fedd:c19c prefixlen 64 scopeid 0x20<link> ether 00:0c:29:dd:c1:9c txqueuelen 1000 (Ethernet) RX packets 267796 bytes 27852817 (26.5 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 4268 bytes 556507 (543.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 0 (Local Loopback) RX packets 56 bytes 4760 (4.6 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 56 bytes 4760 (4.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 CentOS 7：ifconfig命令显示参数详解eno1677736:网卡名称 inet：ip地址 netmask：子网掩码 broadcast：广播地址 UP：网卡表示激活状态 BROADCAST：支持广播功能 MULTICAST：支持组播功能 RUNNING：处于运行状态 mtu：网卡的最大传输单元 inet6：表示IPV6地址 ether：以太网地址，表示mac地址 txqueuelen：传输队列长度 RX packets 267796 bytes 27852817 (26.5 MiB)：接收到报文的数量，后面表示接 收到所有报文的大小 RX errors：接收到错误报文的个数 dropped：丢包的数量 overruns：溢出的 TX packets 4268 bytes 556507 (543.4 KiB)：传出到报文的数量，后面表示传出所 有报文的大小 TX errors：传出报文的错误数量 dropped：发送出去丢包数量 此处为CentOS 6上使用ifconfig的显示（注意：不标明的都默认指CentOS7，当与CentOS不同时会标注） # ifconfig eth0 Link encap:Ethernet HWaddr 00:0C:29:69:45:7B inet addr:172.18.251.87 Bcast:172.18.255.255 Mask:255.255.0.0 inet6 addr: fe80::20c:29ff:fe69:457b/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:303612 errors:0 dropped:0 overruns:0 frame:0 TX packets:2296 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:31934172 (30.4 MiB) TX bytes:261862 (255.7 KiB) eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85 inet addr:192.168.200.3 Bcast:192.168.200.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:fe69:4585/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:292609 errors:0 dropped:0 overruns:0 frame:0 TX packets:202 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:30767674 (29.3 MiB) TX bytes:26126 (25.5 KiB) 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:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) CentOS 6：ifconfig命令显示参数详解eth0:网卡名称 Link encap：接口类型 inet addr：ip地址 Bcast：广播地址 Mask：子网掩码 inet6 addr：IPV6地址 UP：网卡表示激活状态 BROADCAST：支持广播功能 MULTICAST：支持组播功能 RUNNING：处于运行状态 mtu：网卡的最大传输单元 ether：以太网地址，表示mac地址 txqueuelen：传输队列长度 RX packets 接收到报文的数量 errors：接收到错误报文的个数 dropped：丢包的数量 overruns：溢出的 TX packets 传出到报文的数量 errors：传出报文的错误数量 dropped：丢包的数量 overruns：溢出的 RX bytes: 接收到报文的总大小 TX bytes: 传输报文的总大小 # ifconfig -a eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 172.18.250.108 netmask 255.255.0.0 broadcast 172.18.255.255 inet6 fe80::20c:29ff:fedd:c19c prefixlen 64 scopeid 0x20<link> ether 00:0c:29:dd:c1:9c txqueuelen 1000 (Ethernet) RX packets 267877 bytes 27861934 (26.5 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 4283 bytes 559025 (545.9 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 eno33554984: flags=4098<BROADCAST,MULTICAST> mtu 1500 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) RX packets 257603 bytes 26825123 (25.5 MiB) RX errors 0 dropped 269 overruns 0 frame 0 TX packets 38 bytes 3900 (3.8 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 0 (Local Loopback) RX packets 56 bytes 4760 (4.6 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 56 bytes 4760 (4.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 可以指定接口名称，进行单独查看 # ifconfig eno33554984 eno33554984: flags=4098<BROADCAST,MULTICAST> mtu 1500 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) RX packets 257603 bytes 26825123 (25.5 MiB) RX errors 0 dropped 269 overruns 0 frame 0 TX packets 38 bytes 3900 (3.8 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 修改网络配置：ifconfig [-v] interface [aftype] options | address … 方式一： # ifconfig eno33554984 192.168.200.5/24 up # ifconfig eno33554984 eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.200.5 netmask 255.255.255.0 broadcast 192.168.200.255 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) RX packets 259004 bytes 26985088 (25.7 MiB) RX errors 0 dropped 271 overruns 0 frame 0 TX packets 40 bytes 4020 (3.9 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 # 注意此配置仅限临时生效，重启网络服务或者重启系统，内核会重读配置文件，将配置文件中的参数在执行一遍. 方式二： # ifconfig eno33554984 192.168.100.5 netmask 255.255.255.0 up # ifconfig eno33554984 eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.100.5 netmask 255.255.255.0 broadcast 192.168.100.255 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) RX packets 260398 bytes 27138591 (25.8 MiB) RX errors 0 dropped 273 overruns 0 frame 0 TX packets 40 bytes 4020 (3.9 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 2、route命令：查看及管理路由（route – show / manipulate the IP routing table）命令格式：route add [-net|-host] target [netmask Nm] [gw GW] [[dev] If] -net：表示添加网络路由 -host：表示添加主机路由 gw：为默认网关 查看： route -n # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736 172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736 192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984 添加路由：# route add -net 10.0.0.0/8 gw 192.168.100.5 dev eno33554984 # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736 10.0.0.0 192.168.100.5 255.0.0.0 UG 0 0 0 eno33554984 172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736 192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984 删除路由：# route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736 10.0.0.0 192.168.100.5 255.0.0.0 UG 0 0 0 eno33554984 172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736 192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984 # route del -net 10.0.0.0/8 # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736 172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736 192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984 3、netstat命令：打印网络连接，路由表，接口等信息（Print network connections, routing tables, interface statis﹖ics, masquerade connections, and multicast memberships）显示网络连接：netstat [–tcp|-t] [–udp|-u] [–udplite|-U] [–sctp|-S] [–raw|-w] [–listening|-l] [–all|-a] [–numeric|-n] [–extend|-e[–extend|-e]] [–program|-p] -t：TCP协议的相关连接，连接均有其状态 -u：UDP协议相关的连接 -w：raw socket相关的；连接 -l：处于监听状态的连接 -a：所有状态 -n：以数字格式显示IP和Port -e：扩展格式 -p：显示相关的进程及PID # 常用组合： -tan，-una，-tnl，-unl，-tunlp，-antup # netstat -tan Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:6010 0.0.0.0:* LISTEN tcp 0 0 127.0.0.1:6011 0.0.0.0:* LISTEN tcp 0 52 172.18.250.108:22 172.18.4.1:49701 ESTABLISHED tcp 0 0 172.18.250.108:22 172.18.4.1:49924 ESTABLISHED tcp6 0 0 :::22 :::* LISTEN tcp6 0 0 ::1:631 :::* LISTEN tcp6 0 0 ::1:25 :::* LISTEN tcp6 0 0 ::1:6010 :::* LISTEN tcp6 0 0 ::1:6011 :::* LISTEN # netstat -uan Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State udp 0 0 0.0.0.0:10042 0.0.0.0:* udp 0 0 127.0.0.1:323 0.0.0.0:* udp 0 0 0.0.0.0:68 0.0.0.0:* udp6 0 0 ::1:323 :::* udp6 0 0 :::50626 :::* # netstat -tunlp Active Internet connections (only servers) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1054/sshd tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 1052/cupsd tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1143/master tcp 0 0 127.0.0.1:6010 0.0.0.0:* LISTEN 1190/sshd: root@pts tcp 0 0 127.0.0.1:6011 0.0.0.0:* LISTEN 5116/sshd: root@pts tcp6 0 0 :::22 :::* LISTEN 1054/sshd tcp6 0 0 ::1:631 :::* LISTEN 1052/cupsd tcp6 0 0 ::1:25 :::* LISTEN 1143/master tcp6 0 0 ::1:6010 :::* LISTEN 1190/sshd: root@pts tcp6 0 0 ::1:6011 :::* LISTEN 5116/sshd: root@pts udp 0 0 0.0.0.0:10042 0.0.0.0:* 4399/dhclient udp 0 0 127.0.0.1:323 0.0.0.0:* 752/chronyd udp 0 0 0.0.0.0:68 0.0.0.0:* 4399/dhclient udp6 0 0 ::1:323 :::* 752/chronyd udp6 0 0 :::50626 :::* 4399/dhclient # netstat -antup Active Internet connections (servers and established) Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1054/sshd tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN 1052/cupsd tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1143/master tcp 0 0 127.0.0.1:6010 0.0.0.0:* LISTEN 1190/sshd: root@pts tcp 0 0 127.0.0.1:6011 0.0.0.0:* LISTEN 5116/sshd: root@pts tcp 0 52 172.18.250.108:22 172.18.4.1:49701 ESTABLISHED 1190/sshd: root@pts tcp 0 0 172.18.250.108:22 172.18.4.1:49924 ESTABLISHED 5116/sshd: root@pts tcp6 0 0 :::22 :::* LISTEN 1054/sshd tcp6 0 0 ::1:631 :::* LISTEN 1052/cupsd tcp6 0 0 ::1:25 :::* LISTEN 1143/master tcp6 0 0 ::1:6010 :::* LISTEN 1190/sshd: root@pts tcp6 0 0 ::1:6011 :::* LISTEN 5116/sshd: root@pts udp 0 0 0.0.0.0:10042 0.0.0.0:* 4399/dhclient udp 0 0 127.0.0.1:323 0.0.0.0:* 752/chronyd udp 0 0 0.0.0.0:68 0.0.0.0:* 4399/dhclient udp6 0 0 ::1:323 :::* 752/chronyd udp6 0 0 :::50626 :::* 4399/dhclient 显示路由表：netstat -rn-r：显示内核路由表 -n：数字格式显示
# netstat -rn
Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
0.0.0.0 172.18.0.1 0.0.0.0 UG 0 0 0 eno16777736
10.0.0.0 192.168.100.5 255.0.0.0 UG 0 0 0 eno33554984
172.18.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eno16777736
192.168.100.0 0.0.0.0 255.255.255.0 U 0 0 0 eno33554984
显示借口的统计数据：netstat {–interfaces|-I|-i} [iface] [–all|-a] [–extend|-e] [–verbose|-v] [–program|-p] [–numeric|-n] 所有接口： netstat -i # netstat -i Kernel Interface table Iface MTU RX-OK RX-ERR RX-DRP RX-OVR TX-OK TX-ERR TX-DRP TX-OVR Flg eno16777 1500 295676 0 0 0 5992 0 0 0 BMRU eno33554 1500 281789 0 313 0 40 0 0 0 BMRU lo 65536 60 0 0 0 60 0 0 0 LRU 具体值： Iface：借口 MTU：最大传输单元 RX-OK：成功接收报文的数量 RX-ERR：失败的传输报文的数量 RX-DRP：接收丢弃的报文数量 RX-OVR：接收溢出的报文数量 TX-OK：成功传输报文的数量 TX-ERR：失败的传输报文的数量 TX-DRP：传出丢弃的传输数量 TX-OVR：传出溢出的传输数量 Flg：标志 4、ifup/ifdown命令：# 注意：通过配置文件/etc/sysconfig/network-scripts/ifcfg-IFACE来识别接口并完成配置 # 此处在显示上CentOS 6与CentOS 7有所不同 CentOS 6： 在使用ifdown命令时，禁用的接口用ifconfig命令显示不出来，且在显示中也没有UP选项，如需显示需要指定接口或者使用-a选项 # ifconfig eth0 Link encap:Ethernet HWaddr 00:0C:29:69:45:7B inet addr:172.18.251.87 Bcast:172.18.255.255 Mask:255.255.0.0 inet6 addr: fe80::20c:29ff:fe69:457b/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:320170 errors:0 dropped:0 overruns:0 frame:0 TX packets:2653 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:33769657 (32.2 MiB) TX bytes:313476 (306.1 KiB) eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85 inet addr:192.168.200.3 Bcast:192.168.200.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:fe69:4585/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:306513 errors:0 dropped:0 overruns:0 frame:0 TX packets:218 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:32321812 (30.8 MiB) TX bytes:27212 (26.5 KiB) 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:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) # ifdown eth1 # ifconfig eth0 Link encap:Ethernet HWaddr 00:0C:29:69:45:7B inet addr:172.18.251.87 Bcast:172.18.255.255 Mask:255.255.0.0 inet6 addr: fe80::20c:29ff:fe69:457b/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:319600 errors:0 dropped:0 overruns:0 frame:0 TX packets:2601 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:33705819 (32.1 MiB) TX bytes:305610 (298.4 KiB) 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:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) # ifconfig eth1 eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85 BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:306469 errors:0 dropped:0 overruns:0 frame:0 TX packets:211 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:32316117 (30.8 MiB) TX bytes:26744 (26.1 KiB) # ifup eth1 Determining if ip address 192.168.200.3 is already in use for device eth1... # ifconfig eth1 eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85 inet addr:192.168.200.3 Bcast:192.168.200.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:fe69:4585/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:308152 errors:0 dropped:0 overruns:0 frame:0 TX packets:230 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:32503780 (30.9 MiB) TX bytes:28040 (27.3 KiB) CentOS 7：在CentOS 7 上用ifdown命令禁用网卡UP选项不会消失，但是IP没有显示，此处与CentOS 6相同 # ifconfig eno33554984 eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.100.3 netmask 255.255.255.0 broadcast 192.168.100.255 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) RX packets 313238 bytes 33067566 (31.5 MiB) RX errors 0 dropped 349 overruns 0 frame 0 TX packets 42 bytes 4140 (4.0 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 # ifdown eno33554984 Device 'eno33554984' successfully disconnected. # ifconfig eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 172.18.250.108 netmask 255.255.0.0 broadcast 172.18.255.255 inet6 fe80::20c:29ff:fedd:c19c prefixlen 64 scopeid 0x20<link> ether 00:0c:29:dd:c1:9c txqueuelen 1000 (Ethernet) RX packets 327832 bytes 34538419 (32.9 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 6428 bytes 919810 (898.2 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) RX packets 313451 bytes 33089849 (31.5 MiB) RX errors 0 dropped 349 overruns 0 frame 0 TX packets 42 bytes 4140 (4.0 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 0 (Local Loopback) RX packets 64 bytes 5440 (5.3 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 64 bytes 5440 (5.3 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 # ifup eno33554984 Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/12) # ifconfig eno33554984 eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.100.3 netmask 255.255.255.0 broadcast 192.168.100.255 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) RX packets 314723 bytes 33233696 (31.6 MiB) RX errors 0 dropped 349 overruns 0 frame 0 TX packets 44 bytes 4260 (4.1 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 5、配置主机名：hostname命令： 查看：hostname 配置：hostname HOSTNAME 当前系统有效，重启后无效 # hostname centos6.7 # hostname myserver # hostname myserver hostnamectl命令（CentOS 7）： hostnamectl status：显示当前主机名信息 hostnamectl set-hostname：设定主机名，永久有效 # hostnamectl status Static hostname: centos7 Icon name: computer-vm Chassis: vm Machine ID: 94b3ec34f75d44df93cc011c79159864 Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7 Virtualization: vmware Operating System: CentOS Linux 7 (Core) CPE OS Name: cpe:/o:centos:centos:7 Kernel: Linux 3.10.0-327.el7.x86_64 Architecture: x86-64 # hostnamectl set-hostname centos7.2 # hostnamectl status Static hostname: centos7.2 Icon name: computer-vm Chassis: vm Machine ID: 94b3ec34f75d44df93cc011c79159864 Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7 Virtualization: vmware Operating System: CentOS Linux 7 (Core) CPE OS Name: cpe:/o:centos:centos:7 Kernel: Linux 3.10.0-327.el7.x86_64 Architecture: x86-64 # 注意hostname在Centos 7上面也可以使用，但是设置后显示临时主机名 例： # hostnamectl status Static hostname: centos7.2 Icon name: computer-vm Chassis: vm Machine ID: 94b3ec34f75d44df93cc011c79159864 Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7 Virtualization: vmware Operating System: CentOS Linux 7 (Core) CPE OS Name: cpe:/o:centos:centos:7 Kernel: Linux 3.10.0-327.el7.x86_64 Architecture: x86-64 # hostname centos777 # hostnamectl status Static hostname: centos7.2 Transient hostname: hello Icon name: computer-vm Chassis: vm Machine ID: 94b3ec34f75d44df93cc011c79159864 Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7 Virtualization: vmware Operating System: CentOS Linux 7 (Core) CPE OS Name: cpe:/o:centos:centos:7 Kernel: Linux 3.10.0-327.el7.x86_64 Architecture: x86-64 # hostname centos777 配置文件： CentOS6：/etc/sysconfig/network HOSTNAME=<HOSTNAME> # hostname myserver # vim /etc/sysconfig/network # cat /etc/sysconfig/network NETWORKING=yes HOSTNAME=mycentos6 # hostname myserver CentOS7：/etc/hostname HOSTNAME # hostnamectl status Static hostname: centos7 Icon name: computer-vm Chassis: vm Machine ID: 94b3ec34f75d44df93cc011c79159864 Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7 Virtualization: vmware Operating System: CentOS Linux 7 (Core) CPE OS Name: cpe:/o:centos:centos:7 Kernel: Linux 3.10.0-327.el7.x86_64 Architecture: x86-64 # vim /etc/hostname # cat /etc/hostname mycentos7 # hostnamectl status Static hostname: centos7 Icon name: computer-vm Chassis: vm Machine ID: 94b3ec34f75d44df93cc011c79159864 Boot ID: 174d10ff65ef4f7d82721fc7b08f6bf7 Virtualization: vmware Operating System: CentOS Linux 7 (Core) CPE OS Name: cpe:/o:centos:centos:7 Kernel: Linux 3.10.0-327.el7.x86_64 Architecture: x86-64 # 注意：在CentOS 6中此方法不会立即生效，但是在CentOS 7中会立即生效 6、配置DNS服务器指向： 配置文件：/etc/resolv.conf nameserverDNS_SERVER_IP 如何测试（host/nslookup/dig）: # dig -t A FQDN FQDN –> IP # dig -x IP IP –> FQDN # dig 命令的好处在于，他不检查hosts文件中的定义，直接去dns服务器解析 三、iproute家族配置管理 1、ip命令show / manipulate routing, devices, policy routing and tunnels 查看和配置 路由表、设备、策略路由等 ip [ OPTIONS ] OBJECT { COMMAND | help } OBJECT := { link | addr | route | netns } a、ip link 网络设备配置（network device configuration） 1、 ip link set：改变设备属性 （1）dev NAME (default)：指明要管理的设备，dev关键字可省略； （2）up和down： # ip link set eno33554984 down # ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff 3: eno33554984: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff # ip link set eno33554984 up # ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff 3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff （3）multicast on或multicast off：启用或禁用多播功能； # 关闭后可以看到没有UP选项，表示此网卡已关闭 （4）name NAME：重命名接口 # ip link set eno33554984 down # ip link set eno33554984 name eno666777888 # ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff 3: eno666777888: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff # 改名时需要关闭网卡设备 （5）mtu NUMBER：设置MTU的大小，默认为1500； # ip link set eno666777888 mtu 1000 # ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff 3: eno666777888: <BROADCAST,MULTICAST> mtu 1000 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff （6）netns PID：ns为namespace，用于将接口移动到指定的网络名称空间；（在后面会详细讲解） 2、ip link show：列出设备属性 # ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff 3: eno666777888: <BROADCAST,MULTICAST> mtu 1000 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff # ip link show eno666777888 3: eno666777888: <BROADCAST,MULTICAST> mtu 1000 qdisc pfifo_fast state DOWN mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff 3、 ip link help：显示简要使用帮助 b、ip netns # 注意：此命令仅在CentOS 7中支持管理网络名称空间（manage network namespaces） ip netns list：列出所有的netns # ip netns list myspace ip netns add NAME：创建指定的netns # ip netns add space1 # ip netns list space1 myspace ip netns del NAME：删除指定的netns # ip netns del myspace # ip netns list space1 ip netns exec NAME COMMAND：在指定的netns中运行命令 # ip link set eno666777888 netns space1 # ip link show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 2: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff # 加入名称空间后 使用ip link show查看，可以看到此处看不到了eno66677788 # ip netns exec space1 ip link show 1: lo: <LOOPBACK> mtu 65536 qdisc noop state DOWN mode DEFAULT link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 3: eno666777888: <BROADCAST,MULTICAST> mtu 1000 qdisc noop state DOWN mode DEFAULT qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff # 使用此命令可以查看名称空间space1中的网卡设备 c、ip address协议地址管理（protocol address management） ip address add：添加新的协议地址 [label NAME]：为额外添加的地址指明接口别名 # ip add add label eno33554984:0 10.0.0.100/8 dev eno33554984 # ifconfig eno16777736: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 172.18.250.108 netmask 255.255.0.0 broadcast 172.18.255.255 inet6 fe80::20c:29ff:fedd:c19c prefixlen 64 scopeid 0x20<link> ether 00:0c:29:dd:c1:9c txqueuelen 1000 (Ethernet) RX packets 372250 bytes 39402750 (37.5 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 9582 bytes 1347144 (1.2 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1000 inet 192.168.200.2 netmask 255.255.255.0 broadcast 0.0.0.0 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) RX packets 344492 bytes 36539558 (34.8 MiB) RX errors 0 dropped 365 overruns 0 frame 0 TX packets 48 bytes 4500 (4.3 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 eno33554984:0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1000 inet 10.0.0.100 netmask 255.0.0.0 broadcast 0.0.0.0 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 0 (Local Loopback) RX packets 76 bytes 6460 (6.3 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 76 bytes 6460 (6.3 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 [broadcast ADDRESS]：广播地址；会根据IP和NETMASK自动计算得到 [scope SCOPE_VALUE]：作用域，默认设置为global global：全局可用； link：接口可用； host：仅本机可用；
# ip addr show eno33554984
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
inet 192.168.200.2/24 scope global eno33554984
valid_lft forever preferred_lft forever
inet 10.0.0.100/8 scope global eno33554984:0
valid_lft forever preferred_lft forever
inet 10.0.0.200/8 scope global secondary eno33554984
valid_lft forever preferred_lft forever
ip address delete：删除协议地址
# ip addr show eno33554984
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
inet 192.168.200.2/24 scope global eno33554984
valid_lft forever preferred_lft forever
inet 10.0.0.100/8 scope global eno33554984:0
valid_lft forever preferred_lft forever
inet 10.0.0.200/8 scope global secondary eno33554984
valid_lft forever preferred_lft forever
# ip add del 192.168.200.2/24 dev eno33554984
# ip addr show eno33554984
3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff
inet 10.0.0.100/8 scope global eno33554984:0
valid_lft forever preferred_lft forever
inet 10.0.0.200/8 scope global secondary eno33554984
valid_lft forever preferred_lft forever
ip address show：查看协议地址 # ip add show 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN 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: eno16777736: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:dd:c1:9c brd ff:ff:ff:ff:ff:ff inet 172.18.250.108/16 brd 172.18.255.255 scope global dynamic eno16777736 valid_lft 63185sec preferred_lft 63185sec inet6 fe80::20c:29ff:fedd:c19c/64 scope link valid_lft forever preferred_lft forever 3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff inet 10.0.0.100/8 scope global eno33554984:0 valid_lft forever preferred_lft forever inet 10.0.0.200/8 scope global secondary eno33554984 valid_lft forever preferred_lft forever ip address flush：清除协议地址（清除某设备上的所有地址） # ip add show eno33554984 3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff inet 10.0.0.100/8 scope global eno33554984:0 valid_lft forever preferred_lft forever inet 10.0.0.200/8 scope global secondary eno33554984 valid_lft forever preferred_lft forever # ip add flush dev eno33554984 # ip add show eno33554984 3: eno33554984: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1000 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:dd:c1:a6 brd ff:ff:ff:ff:ff:ff d、ip route路由表管理（routing table management） ip route add：添加新的路由 # ip route add 20.0.0.0/8 via 10.0.0.20 dev eno33554984 # ip route show default via 172.18.0.1 dev eno16777736 proto static metric 100 10.0.0.0/8 dev eno33554984 proto kernel scope link src 10.0.0.200 20.0.0.0/8 via 10.0.0.20 dev eno33554984 172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100 192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2 192.168.100.0/24 dev eno33554984 proto kernel scope link src 192.168.100.2 ip route change：修改路由 # ip route change 20.0.0.0/8 via 172.18.250.108 dev eno16777736 # ip route show default via 172.18.0.1 dev eno16777736 proto static metric 100 10.0.0.0/8 dev eno33554984 proto kernel scope link src 10.0.0.200 20.0.0.0/8 via 172.18.250.108 dev eno16777736 172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100 192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2 192.168.100.0/24 dev eno33554984 proto kernel scope link src 192.168.100.2 ip route replace：改变或者添加新的路由（表示如果没有就新添加） ip route add TYPE PREFIX via GW [dev IFACE] [src SOURCE_IP] ip route delete：删除路由 # ip route show default via 172.18.0.1 dev eno16777736 proto static metric 100 10.0.0.0/8 dev eno33554984 proto kernel scope link src 10.0.0.200 20.0.0.0/8 via 172.18.250.108 dev eno16777736 172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100 192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2 192.168.100.0/24 dev eno33554984 proto kernel scope link src 192.168.100.2 # ip route del 10.0.0.0/8 # ip route show default via 172.18.0.1 dev eno16777736 proto static metric 100 20.0.0.0/8 via 172.18.250.108 dev eno16777736 172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100 192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2 192.168.100.0/24 dev eno33554984 proto kernel scope link src 192.168.100.2 ip route show：查看路由 ip route flush：删除路由表 # ip route flush 192.168.100/24 # ip route show default via 172.18.0.1 dev eno16777736 proto static metric 100 20.0.0.0/8 via 172.18.250.108 dev eno16777736 172.18.0.0/16 dev eno16777736 proto kernel scope link src 172.18.250.108 metric 100 192.168.20.0/24 dev eno33554984 proto kernel scope link src 192.168.20.2 ip route get：查看一条路由
# ip route get 20.0.0.0/8
20.0.0.0 dev eno16777736 src 172.18.250.108
cache
2、ss命令另一个套接字管理程序（another utility to investigate sockets） ss [options] [FILTER] 选项： -t：TCP协议的相关连接 -u：UDP相关的连接 -w：raw socket相关的连接 -l：监听状态的连接 -a：所有状态的连接 -n：数字格式 -p：相关的程序及其PID -e：扩展格式信息 -m：内存用量 -o：计时器信息 # 用法与netstat相同，组合方式也可以参照netstat 常用组合：-tan，-una，-tnl，-unl，-tunlp，-antup # ss -tan State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 *:22 *:* LISTEN 0 128 127.0.0.1:631 *:* LISTEN 0 100 127.0.0.1:25 *:* LISTEN 0 128 127.0.0.1:6010 *:* LISTEN 0 128 127.0.0.1:6011 *:* ESTAB 0 52 172.18.250.108:22 172.18.4.1:49701 ESTAB 0 0 172.18.250.108:22 172.18.4.1:49924 LISTEN 0 128 :::22 :::* LISTEN 0 128 ::1:631 :::* LISTEN 0 100 ::1:25 :::* LISTEN 0 128 ::1:6010 :::* LISTEN 0 128 ::1:6011 :::* # ss -uan State Recv-Q Send-Q Local Address:Port Peer Address:Port UNCONN 0 0 *:10042 *:* UNCONN 0 0 127.0.0.1:323 *:* UNCONN 0 0 *:68 *:* UNCONN 0 0 ::1:323 :::* UNCONN 0 0 :::50626 :::* FILTER := [ state TCP-STATE ] [ EXPRESSION ] [EXPRESSION] dport = sport = # ss -tan '( dport = 22 or sport = 22 )' State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 *:22 *:* ESTAB 0 52 172.18.250.108:22 172.18.4.1:49701 ESTAB 0 0 172.18.250.108:22 172.18.4.1:49924 LISTEN 0 128 :::22 :::* 四、管理网络属性之配置文件 IP/NETMASK/GW/DNS等配置文件：/etc/sysconfig/network-scripts/ifcfg-IFACE 路由相关的配置文件：/etc/sysconfig/networkj-scripts/route-IFACE 命令方式修改： CentOS 6：system-config-network setup CentOS 7：nmtui ifcfg-IFACE文件中的参数： DEVICE：此配置文件对应的设备的名称； ONBOOT：在系统引导过程中，是否激活此接口； UUID：此设备的惟一标识； IPV6INIT：是否初始化IPv6； BOOTPROTO：激活此接口时使用什么协议来配置接口属性，常用的有dhcp、bootp、static、none； TYPE：接口类型，常见的有Ethernet, Bridge； DNS1：第一DNS服务器指向； DNS2：备用DNS服务器指向； DOMAIN：DNS搜索域； IPADDR： IP地址； NETMASK：子网掩码；CentOS 7支持使用PREFIX以长度方式指明子网掩码； GATEWAY：默认网关； USERCTL：是否允许普通用户控制此设备； PEERDNS：如果BOOTPROTO的值为“dhcp”，是否允许dhcp_server分配的dns服务器指向覆盖本地手动指定的DNS服务器指向；默认为允许； HWADDR：设备的MAC地址； NM_CONTROLLED：是否使用NetworkManager服务来控制接口； 示例： CentOS 7： IPV6INIT=yes BOOTPROTO=none DEVICE=eno16777736 ONBOOT=yes UUID=fc03aa9a-32b4-4d25-9576-288a0e3cd39a TYPE=Ethernet DEFROUTE=yes NAME="System eno16777736" PEERDNS=yes IPADDR=172.18.4.1 PREFIX=8 GATEWAY=172.18.0.1 DNS1=202.106.0.20 DNS2=172.18.0.1 CentOS 6： DEVICE=eth0 HWADDR=00:0C:29:69:45:7B TYPE=Ethernet UUID=1e9d304f-319a-4467-ac3c-67159f182f33 ONBOOT=yes NM_CONTROLLED=yes BOOTPROTO=dhcp 网络服务： network NetworkManger 管理网络服务： CentOS 6: service {network|NetworkManager} {start|stop|restart|status} # cat /etc/sysconfig/network-scripts/ifcfg-eth1 DEVICE=eth1 TYPE=Ethernet ONBOOT=yes NM_CONTROLLED=yes BOOTPROTO=none IPADDR=10.0.0.100 PREFIX=8 GATEWAY=10.0.0.1 DNS1=202.106.0.20 # service network restart Shutting down interface eth0: [ OK ] Shutting down interface eth1: [ OK ] Shutting down loopback interface: [ OK ] Bringing up loopback interface: [ OK ] Bringing up interface eth0: Determining IP information for eth0... done. [ OK ] Bringing up interface eth1: Determining ip address 10.0.0.100 is already in use for device eth1.. [ OK ] # ifconfig eth1 eth1 Link encap:Ethernet HWaddr 00:0C:29:69:45:85 inet addr:10.0.0.100 Bcast:10.255.255.255 Mask:255.0.0.0 inet6 addr: fe80::20c:29ff:fe69:4585/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:411362 errors:0 dropped:0 overruns:0 frame:0 TX packets:240 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:44602847 (42.5 MiB) TX bytes:28728 (28.0 KiB) CentOS 7: systemctl {start|stop|restart|status} {network|NetworkManager}.service # cat /etc/sysconfig/network-scripts/ifcfg-eno33554984 # Generated by parse-kickstart BOOTPROTO=none DEVICE=eno33554984 ONBOOT=yes TYPE=Ethernet DEFROUTE=yes IPV4_FAILURE_FATAL=no NAME="System eno33554984" PEERDNS=yes PEERROUTES=yes IPADDR=20.0.0.100 PREFIX=24 GATEWAY=20.0.0.1 DNS1=202.106.0.20 # systemctl restart network.service # ifconfig eno33554984 eno33554984: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1000 inet 20.0.0.100 netmask 255.255.255.0 broadcast 20.0.0.255 ether 00:0c:29:dd:c1:a6 txqueuelen 1000 (Ethernet) RX packets 406943 bytes 44125370 (42.0 MiB) RX errors 0 dropped 635 overruns 0 frame 0 TX packets 50 bytes 4620 (4.5 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 配置文件配置路由：/etc/sysconfig/network-scripts/route-IFACE 支持两种配置方式，但不可混用； (1) 每行一个路由条目： TARGET via GW # cat /etc/sysconfig/network-scripts/route-eno33554984 172.0.0.0/8 via 20.0.0.100 # systemctl restart network.service # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736 0.0.0.0 20.0.0.1 0.0.0.0 UG 101 0 0 eno33554984 20.0.0.0 0.0.0.0 255.255.255.0 U 100 0 0 eno33554984 172.0.0.0 20.0.0.100 255.0.0.0 UG 100 0 0 eno33554984 172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736 (2) 每三行一个路由条目： ADDRESS#=TARGET NETMASK#=MASK GATEWAY#=NEXTHOP # cat /etc/sysconfig/network-scripts/route-eno33554984 ADDRESS0=11.0.0.0 NETMASK0=255.0.0.0 GATEWAY0=20.0.0.100 # systemctl restart network.service # route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 172.18.0.1 0.0.0.0 UG 100 0 0 eno16777736 0.0.0.0 20.0.0.1 0.0.0.0 UG 101 0 0 eno33554984 11.0.0.0 20.0.0.100 255.0.0.0 UG 100 0 0 eno33554984 20.0.0.0 0.0.0.0 255.255.255.0 U 100 0 0 eno33554984 172.18.0.0 0.0.0.0 255.255.0.0 U 100 0 0 eno16777736 对于CentOS 7的网络属性管理就写到这里了，感觉写的不错可以给点个赞。
作者： Q/A：如有问题请慷慨提出 (责任编辑：IT) |