Centos7系统配置上的变化（三）为网络接口添加多IP

时间：2015-01-29 23:48:12 收藏：0 阅读：324

原文 Centos7系统配置上的变化（三）为网络接口添加多IP

实验的方法有 nmtui, 编辑ifcfg-*文件，ip addr 指令，子连接配置文件。
一、nmtui手工添加IP

看一下当前网络设备的IP，为了精简指令输出，指令就要复杂一些了：

view source print ?

01.[root@centos7 ~]# nmcli -t -f IP4.ADDRESS dev show enp0s3

02.IP4.ADDRESS[1]:ip = 192.168.150.110/24, gw = 192.168.150.254

03.[root@centos7 ~]#

04.[root@centos7 ~]# ip addr show enp0s3 scope global

05.2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

06.link/ether 08:00:27:15:35:d2 brd ff:ff:ff:ff:ff:ff

07.inet 192.168.150.110/24 brd 192.168.150.255 scope global enp0s3

08.valid_lft forever preferred_lft forever

09.[root@centos7 ~]#

10.[root@centos7 ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0

11.......

12.IPADDR0=192.168.150.110

13.PREFIX0=24

14.GATEWAY0=192.168.150.254

15.DNS1=192.168.150.254

16.HWADDR=08:00:27:15:35:D2

17.IPADDR1=192.168.150.111

18.PREFIX1=24

19.[root@centos7 ~]#

新IP已经被加入到ifcfg-eth0中，原始地址的关键字是 IPADDR0、PREFIX0，新地址的关键字是 IPADDR1、PREFIX1 。

view source print ?

1.[root@centos7 ~]# nmcli con load /etc/sysconfig/network-scripts/ifcfg-eth0

2.[root@centos7 ~]#

3.[root@centos7 ~]# nmcli -t -f IP4.ADDRESS dev show enp0s3

4.IP4.ADDRESS[1]:ip = 192.168.150.110/24, gw = 192.168.150.254

5.[root@centos7 ~]# [root@centos7 ~]# ip addr show enp0s3 scope global 2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 08:00:27:15:35:d2 brd ff:ff:ff:ff:ff:ff inet 192.168.150.110/24 brd192.168.150.255 scope global enp0s3 valid_lft forever preferred_lft forever [root@centos7 ~]#

load connection 后，NetworkManager 也没有知晓新增IP，新增IP也没有出现在 ip addr show 中。

view source print ?

01.[root@centos7 ~]# systemctl restart network

02.[root@centos7 ~]#

03.[root@centos7 ~]# nmcli -t -f IP4.ADDRESS dev show enp0s3

04.IP4.ADDRESS[1]:ip = 192.168.150.110/24, gw = 192.168.150.254

05.IP4.ADDRESS[2]:ip = 192.168.150.111/24, gw = 192.168.150.254

06.[root@centos7 ~]#

07.[root@centos7 ~]# ip addr show enp0s3 scope global

08.2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

09.link/ether 08:00:27:15:35:d2 brd ff:ff:ff:ff:ff:ff

10.inet 192.168.150.110/24 brd 192.168.150.255 scope global enp0s3

11.valid_lft forever preferred_lft forever

12.[root@centos7 ~]#

13.[root@centos7 ~]#

14.[root@centos7 ~]# ping 192.168.150.111

15.PING 192.168.150.111 (192.168.150.111) 56(84) bytes of data.

16.From 192.168.150.110 icmp_seq=1 Destination Host Unreachable

17.From 192.168.150.110 icmp_seq=2 Destination Host Unreachable

18.......

19.[root@centos7 ~]#

重启network服务后，NetworkManager 知晓新增IP了，但新增IP还是没有生效。

view source print ?

01.[root@centos7 ~]# nmcli dev connect enp0s3

02.[root@centos7 ~]#

03.[root@centos7 ~]#

04.[root@centos7 ~]# nmcli -t -f IP4.ADDRESS dev show enp0s3

05.IP4.ADDRESS[1]:ip = 192.168.150.110/24, gw = 192.168.150.254

06.IP4.ADDRESS[2]:ip = 192.168.150.111/24, gw = 192.168.150.254

07.[root@centos7 ~]#

08.[root@centos7 ~]#

09.[root@centos7 ~]# ip addr show enp0s3 scope global

10.2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

11.link/ether 08:00:27:15:35:d2 brd ff:ff:ff:ff:ff:ff

12.inet 192.168.150.110/24 brd 192.168.150.255 scope global enp0s3

13.valid_lft forever preferred_lft forever

14.inet 192.168.150.111/24 brd 192.168.150.255 scope global secondary enp0s3

15.valid_lft forever preferred_lft forever

16.[root@centos7 ~]#

17.[root@centos7 ~]#

18.[root@centos7 ~]# ping 192.168.150.111

19.PING 192.168.150.111 (192.168.150.111) 56(84) bytes of data.

20.64 bytes from 192.168.150.111: icmp_seq=1 ttl=64 time=0.039 ms

21.64 bytes from 192.168.150.111: icmp_seq=2 ttl=64 time=0.079 ms

22.......

23.[root@centos7 ~]#

重新连接设备 enp0s3，新IP生效了。注意：不需要先断开设备（nmcli dev disconnect enp0s3），断开设备的话ssh立刻断线。重新连接设备的过程中，ssh是不会断线的。

nmtui添加IP后，需要： nmcli con load /etc/sysconfig/network-scripts/ifcfg-eth0 nmcli dev connect enp0s3

二、手工添加IP到ifcfg-eth0

在ifcfg-eth0配置文件中手工添加如下两行： IPADDR2=192.168.150.112 PREFIX2=24
先执行 nmcli con load /etc/sysconfig/network-scripts/ifcfg-eth0 后，在nmtui中可以看到新增IP。（也可以简单的用 nmcli con reload ，reload 和 load的区别自己脑补一下吧。）再执行 nmcli dev connect enp0s3 后，IP 192.168.150.112 才生效的。

手工添加IP到ifcfg-eth0后，需要： nmcli con load /etc/sysconfig/network-scripts/ifcfg-eth0 或 nmcli con reload nmcli dev connect enp0s3

三、用ip addr add指令添加/删除IP，即刻生效，重启不保留。
在线添加IP：

view source print ?

01.[root@centos7 ~]# ip addr add 192.168.150.113/24 dev enp0s3

02.[root@centos7 ~]#

03.[root@centos7 ~]#

04.[root@centos7 ~]# nmcli -t -f IP4.ADDRESS dev show enp0s3

05.IP4.ADDRESS[1]:ip = 192.168.150.110/24, gw = 192.168.150.254

06.IP4.ADDRESS[2]:ip = 192.168.150.111/24, gw = 192.168.150.254

07.IP4.ADDRESS[3]:ip = 192.168.150.112/24, gw = 192.168.150.254

08.IP4.ADDRESS[4]:ip = 192.168.150.113/24, gw = 192.168.150.254

09.[root@centos7 ~]#

10.[root@centos7 ~]#

11.[root@centos7 ~]# ip addr show enp0s3 scope global

12.2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

13.link/ether 08:00:27:15:35:d2 brd ff:ff:ff:ff:ff:ff

14.inet 192.168.150.110/24 brd 192.168.150.255 scope global enp0s3

15.valid_lft forever preferred_lft forever

16.inet 192.168.150.111/24 brd 192.168.150.255 scope global secondary enp0s3

17.valid_lft forever preferred_lft forever

18.inet 192.168.150.112/24 brd 192.168.150.255 scope global secondary enp0s3

19.valid_lft forever preferred_lft forever

20.inet 192.168.150.113/24 scope global secondary enp0s3

21.valid_lft forever preferred_lft forever

22.[root@centos7 ~]#

23.[root@centos7 ~]#

24.[root@centos7 ~]# ping 192.168.150.113

25.PING 192.168.150.113 (192.168.150.113) 56(84) bytes of data.

26.64 bytes from 192.168.150.113: icmp_seq=1 ttl=64 time=0.098 ms

27.64 bytes from 192.168.150.113: icmp_seq=2 ttl=64 time=0.255 ms

28.......

/etc/sysconfig/network-scripts/ifcfg-eth0 配置文件里并没有192.168.150.113，所以重启后该IP不会保留。
在线删除IP：

view source print ?

01.[root@centos7 ~]# ip addr del 192.168.150.113/24 dev enp0s3

02.[root@centos7 ~]#

03.[root@centos7 ~]#

04.[root@centos7 ~]# nmcli -t -f IP4.ADDRESS dev show enp0s3

05.IP4.ADDRESS[1]:ip = 192.168.150.110/24, gw = 192.168.150.254

06.IP4.ADDRESS[2]:ip = 192.168.150.111/24, gw = 192.168.150.254

07.IP4.ADDRESS[3]:ip = 192.168.150.112/24, gw = 192.168.150.254

08.[root@centos7 ~]#

09.[root@centos7 ~]#

10.[root@centos7 ~]# ip addr show enp0s3 scope global

11.2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

12.link/ether 08:00:27:15:35:d2 brd ff:ff:ff:ff:ff:ff

13.inet 192.168.150.110/24 brd 192.168.150.255 scope global enp0s3

14.valid_lft forever preferred_lft forever

15.inet 192.168.150.111/24 brd 192.168.150.255 scope global secondary enp0s3

16.valid_lft forever preferred_lft forever

17.inet 192.168.150.112/24 brd 192.168.150.255 scope global secondary enp0s3

18.valid_lft forever preferred_lft forever

四、使用子连接配置文件 ifcfg-*:n
子连接配置文件是 Centos6 常用的方法，即：如果当前网卡配置文件为 ifcfg-eth0，则子连接配置文件可以为 ifcfg-eth0:1，并且文件中需要写明 DEVICE=eth0:1 ， IPADDR=<新IP地址> 。我们试试在Centos7 中是否也支持。理论上应该是不支持的，因为在Centos7的网络连接配置文件（即 ifcfg-*）中，DEVICE关键字已经具有了新的定义，即我们上篇说的“设备”。参考上篇 http://www.cnblogs.com/panblack/p/Centos7-WhatsNew-02-networking.html

首先注释掉ifcfg-eth0中的其他地址，复制 ifcfg-eth0 为 ifcfg-eth0:1，编辑ifcfg-eth0:1， DEVICE 设为eth0:1 ，IP设为 192.168.150.119 ，然后 nmcli con reload ， nmcli dev con enp0s3

view source print ?

01.[root@centos7 ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0

02.TYPE=Ethernet

03.BOOTPROTO=none

04.DEFROUTE=yes

05.IPV4_FAILURE_FATAL=no

06.IPV6INIT=no

07.IPV6_AUTOCONF=yes

08.IPV6_DEFROUTE=yes

09.IPV6_PEERDNS=yes

10.IPV6_PEERROUTES=yes

11.IPV6_FAILURE_FATAL=no

12.NAME=eth0

13.UUID=295e1841-0ff3-4db9-8800-4e25fc2944da

14.ONBOOT=yes

15.IPADDR0=192.168.150.110

16.PREFIX0=24

17.GATEWAY0=192.168.150.254

18.DNS1=192.168.150.254

19.HWADDR=08:00:27:15:35:D2

20.#IPADDR1=192.168.150.111

21.#PREFIX1=24

22.#IPADDR2=192.168.150.112

23.#PREFIX2=24

24.

25.[root@centos7 ~]#

26.[root@centos7 ~]#

27.[root@centos7 ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0:1

28.TYPE=Ethernet

29.BOOTPROTO=none

30.DEFROUTE=yes

31.IPV4_FAILURE_FATAL=no

32.IPV6INIT=no

33.IPV6_AUTOCONF=yes

34.IPV6_DEFROUTE=yes

35.IPV6_PEERDNS=yes

36.IPV6_PEERROUTES=yes

37.IPV6_FAILURE_FATAL=no

38.NAME=eth0:1

39.DEVICE=eth0:1

40.UUID=295e1841-0ff3-4db9-8800-4e25fc2944da

41.ONBOOT=yes

42.IPADDR0=192.168.150.119

43.PREFIX0=24

44.GATEWAY0=192.168.150.254

45.DNS1=192.168.150.254

46.HWADDR=08:00:27:15:35:D2

47.[root@centos7 ~]#

48.[root@centos7 ~]# nmcli con reload

49.[root@centos7 ~]# nmcli dev connect enp0s3

50.[root@centos7 ~]#

51.[root@centos7 ~]# nmcli -t -f IP4.ADDRESS dev show enp0s3

52.IP4.ADDRESS[1]:ip = 192.168.150.110/24, gw = 192.168.150.254

53.[root@centos7 ~]#

54.[root@centos7 ~]#

55.[root@centos7 ~]# ip addr show enp0s3 scope global

56.2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000

57.link/ether 08:00:27:15:35:d2 brd ff:ff:ff:ff:ff:ff

58.inet 192.168.150.110/24 brd 192.168.150.255 scope global eth0:1

59.valid_lft forever preferred_lft forever

60.[root@centos7 ~]#

可以看到ifcfg-eth0:1里的新IP确实没有生效。
五、总结
ip addr show 中显示的IP才是有效的。 ip addr add 能在线添加IP，立即生效，但重启即丢。 ip addr del 能在线删除IP，立即生效，但重启即丢。 子连接(ifcfg-*:n)已经无效了。 nmtui和编辑ifcfg-eth0 文件效果基本相同，都不能立即生效，必须 load 连接再重新connect网络设备，即： nmcli con load /etc/sysconfig/network-scripts/ifcfg-eth0 或 nmcli reload nmcli dev connect enp0s3