It is a story that solved the problem that ens224 and ens256 do not UP and the IP address cannot be set.
[root@centos ~]# nmcli device
DEVICE TYPE STATE CONNECTION
ens192 ethernet connected ens192
ens224 ethernet connecting (getting IP configuration) Wired connection 1
ens256 ethernet connecting (getting IP configuration) Wired connection 2
lo loopback unmanaged --
First, I tried to change the name of the interface, but I can't see ens224 and ens256 in the first place.
[root@centos network-scripts]# ls -la
total 240
drwxr-xr-x. 2 root root 4096 Oct 8 00:45 .
drwxr-xr-x. 6 root root 4096 Oct 8 00:45 ..
-rw-r--r--. 1 root root 422 Oct 7 01:04 ifcfg-ens192
-rw-r--r--. 1 root root 254 Sep 12 2016 ifcfg-lo
I tried the interface enable command, but I got angry when there was no connection.
[root@centos network-scripts]# nmcli c m eth224 connection.autoconnect yes
Error: unknown connection 'eth224'.
[root@centos network-scripts]# nmcli c down eth224
Error: 'eth224' is not an active connection.
Error: no active connection provided.
When you execute the command to add a connection,
[root@centos network-scripts]# nmcli con add type ethernet ifname ens81
Connection 'ethernet-ens81' (36a6afec-8712-4242-8d75-4cc6d2c9bbf0) successfully added.
[root@centos network-scripts]# nmcli con add type ethernet ifname ens91
Connection 'ethernet-ens91' (b6b6eaac-0593-44c6-a0af-6cdb340a85e4) successfully added.
[root@centos network-scripts]# nmcli device
DEVICE TYPE STATE CONNECTION
ens192 ethernet connected ens192
ens224 ethernet connecting (getting IP configuration) Wired connection 1
ens256 ethernet connecting (getting IP configuration) Wired connection 2
lo loopback unmanaged --
The file is ready!
[root@centos network-scripts]# ls -la
total 248
drwxr-xr-x. 2 root root 4096 Oct 8 16:31 .
drwxr-xr-x. 6 root root 4096 Oct 8 00:45 ..
-rw-r--r--. 1 root root 422 Oct 7 01:04 ifcfg-ens192
-rw-r--r--. 1 root root 319 Oct 8 16:22 ifcfg-ethernet-ens81
-rw-r--r--. 1 root root 319 Oct 8 16:23 ifcfg-ethernet-ens91
-rw-r--r--. 1 root root 254 Sep 12 2016 ifcfg-lo
However, the IP address cannot be set.
[root@centos network-scripts]# nmcli c m ens81 ipv4.method manual ipv4.addr 10.1.81.102/24 10.1.81.21
Error: unknown connection 'ens81'.
When I read the article Poke the corner of the nmcli command, I found that Connection and Device seem to be different.
The name of ens254 that I saw on the nmcli device is actually "Wired connection 1".
[root@centos network-scripts]# nmcli connection show
NAME UUID TYPE DEVICE
Wired connection 1 d7993957-17e7-38ae-8499-289a1d69a331 802-3-ethernet ens224
Wired connection 2 c5323930-cfab-3867-a1c2-89ed3727c83f 802-3-ethernet ens256
ens192 25523ce6-e6f2-4a9c-831c-4ba5a3d36d94 802-3-ethernet ens192
ethernet-ens81 36a6afec-8712-4242-8d75-4cc6d2c9bbf0 802-3-ethernet --
ethernet-ens81-1 6e02b7f5-af7d-4c97-a895-7ceb4a52feae 802-3-ethernet --
ethernet-ens91 b6b6eaac-0593-44c6-a0af-6cdb340a85e4 802-3-ethernet --
ethernet-ens91-1 059e7a43-ef58-4382-8c62-14366341b7f9 802-3-ethernet --
[root@centos network-scripts]# ip add show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
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: ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
link/ether 00:50:56:86:99:7a brd ff:ff:ff:ff:ff:ff
inet 172.22.2.102/16 brd 172.22.255.255 scope global ens192
valid_lft forever preferred_lft forever
inet6 fe80::608f:5a80:8910:3594/64 scope link
valid_lft forever preferred_lft forever
3: ens224: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
link/ether 00:50:56:86:20:c8 brd ff:ff:ff:ff:ff:ff
inet6 fe80::549c:63a:2c22:8109/64 scope link
valid_lft forever preferred_lft forever
4: ens256: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
link/ether 00:50:56:86:82:06 brd ff:ff:ff:ff:ff:ff
inet6 fe80::511d:7bfc:90d2:8df8/64 scope link
valid_lft forever preferred_lft forever
So when I tried to execute the command again with "Wired connection 1", the command passed. However, the interface is not UP.
[root@centos ~]# nmcli c m "Wired connection 1" connection.autoconnect yes
[root@centos ~]# nmcli device
DEVICE TYPE STATE CONNECTION
ens192 ethernet connected ens192
ens224 ethernet connecting (getting IP configuration) Wired connection 1
ens256 ethernet connecting (getting IP configuration) Wired connection 2
lo loopback unmanaged --
[root@centos ~]# nmcli device
When I set the IP address again, it became Connected!
[root@centos ~]# nmcli c m "Wired connection 1" ipv4.method manual ipv4.addr 10.1.81.102/24
[root@centos ~]# nmcli device
DEVICE TYPE STATE CONNECTION
ens192 ethernet connected ens192
ens224 ethernet connected Wired connection 1
ens256 ethernet disconnected --
lo loopback unmanaged --
Try changing the name.
[root@centos ~]# nmcli connection modify "Wired connection 2" connection.id ens91
Error: unknown connection 'Wired connection 2'.
[root@centos ~]# nmcli connection modify "Wired connection 1" connection.id ens81
Error: unknown connection 'Wired connection 1'.
[root@centos ~]# nmcli device
DEVICE TYPE STATE CONNECTION
ens192 ethernet connected ens192
ens224 ethernet connected ens81
ens256 ethernet connected ens91
lo loopback unmanaged --
If you look at the file, the one that is updated is the "ifcfg-Wired_connection_1" file.
[root@centos network-scripts]# pwd
/etc/sysconfig/network-scripts
[root@centos network-scripts]# ls
ifcfg-ens192 ifdown-ipv6 ifup-bnep ifup-sit
ifcfg-ethernet-ens81 ifdown-isdn ifup-eth ifup-Team
ifcfg-ethernet-ens91 ifdown-post ifup-ib ifup-TeamPort
ifcfg-lo ifdown-ppp ifup-ippp ifup-tunnel
ifcfg-Wired_connection_1 ifdown-routes ifup-ipv6 ifup-wireless
ifcfg-Wired_connection_2 ifdown-sit ifup-isdn init.ipv6-global
ifdown ifdown-Team ifup-plip network-functions
ifdown-bnep ifdown-TeamPort ifup-plusb network-functions-ipv6
ifdown-eth ifdown-tunnel ifup-post
ifdown-ib ifup ifup-ppp
ifdown-ippp ifup-aliases ifup-routes
[root@centos network-scripts]# cat ifcfg-Wired_connection_1
HWADDR=00:50:56:86:20:C8
TYPE=Ethernet
BOOTPROTO=none
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=eth81
UUID=d7993957-17e7-38ae-8499-289a1d69a331
ONBOOT=yes
AUTOCONNECT_PRIORITY=-999
IPADDR=10.1.81.102
PREFIX=24
IPV6_PEERDNS=yes
IPV6_PEERROUTES=yes
Therefore, delete this file created earlier.
[root@centos network-scripts]# cat ifcfg-ethernet-ens81
TYPE=Ethernet
BOOTPROTO=dhcp
DEFROUTE=yes
PEERDNS=yes
PEERROUTES=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_PEERDNS=yes
IPV6_PEERROUTES=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=ethernet-ens81
UUID=36a6afec-8712-4242-8d75-4cc6d2c9bbf0
DEVICE=ens81
ONBOOT=yes
The file has been renamed.
[root@centos network-scripts]# ls
ifcfg-ens192 ifdown-isdn ifup-bnep ifup-routes
ifcfg-ens81 ifdown-post ifup-eth ifup-sit
ifcfg-ens91 ifdown-ppp ifup-ib ifup-Team
ifcfg-lo ifdown-routes ifup-ippp ifup-TeamPort
ifdown ifdown-sit ifup-ipv6 ifup-tunnel
ifdown-bnep ifdown-Team ifup-isdn ifup-wireless
ifdown-eth ifdown-TeamPort ifup-plip init.ipv6-global
ifdown-ib ifdown-tunnel ifup-plusb network-functions
ifdown-ippp ifup ifup-post network-functions-ipv6
ifdown-ipv6 ifup-aliases ifup-ppp
The IP address did not change with service restart.
[root@centos squid-4.13]# systemctl restart network.service
[root@centos squid-4.13]# ip add
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
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: ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 100 0
link/ether 00:50:56:86:99:7a brd ff:ff:ff:ff:ff:ff
inet 172.22.2.102/16 brd 172.22.255.255 scope global ens192
valid_lft forever preferred_lft forever
inet6 fe80::608f:5a80:8910:3594/64 scope link
valid_lft forever preferred_lft forever
3: ens224: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 100 0
link/ether 00:50:56:86:20:c8 brd ff:ff:ff:ff:ff:ff
inet 10.1.81.102/24 brd 10.1.81.255 scope global ens224
valid_lft forever preferred_lft forever
inet6 fe80::549c:63a:2c22:8109/64 scope link
valid_lft forever preferred_lft forever
4: ens256: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 100 0
link/ether 00:50:56:86:82:06 brd ff:ff:ff:ff:ff:ff
inet 10.1.91.102/24 brd 10.1.91.255 scope global ens256
valid_lft forever preferred_lft forever
inet6 fe80::511d:7bfc:90d2:8df8/64 scope link
valid_lft forever preferred_lft forever
Looking at the contents of the file, the settings have changed.
[root@centos squid-4.13]# cd /etc/sysconfig/network-scripts
[root@centos network-scripts]# ls
ifcfg-ens192 ifdown-isdn ifup-bnep ifup-routes
ifcfg-ens81 ifdown-post ifup-eth ifup-sit
ifcfg-ens91 ifdown-ppp ifup-ib ifup-Team
ifcfg-lo ifdown-routes ifup-ippp ifup-TeamPort
ifdown ifdown-sit ifup-ipv6 ifup-tunnel
ifdown-bnep ifdown-Team ifup-isdn ifup-wireless
ifdown-eth ifdown-TeamPort ifup-plip init.ipv6-global
ifdown-ib ifdown-tunnel ifup-plusb network-functions
ifdown-ippp ifup ifup-post network-functions-ipv6
ifdown-ipv6 ifup-aliases ifup-ppp
[root@centos network-scripts]# cat ifcfg-ens81
HWADDR=00:50:56:86:20:C8
TYPE=Ethernet
BOOTPROTO=none
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_FAILURE_FATAL=no
IPV6_ADDR_GEN_MODE=stable-privacy
NAME=ens82
UUID=d7993957-17e7-38ae-8499-289a1d69a331
ONBOOT=yes
AUTOCONNECT_PRIORITY=-999
IPADDR=10.1.82.102
PREFIX=24
IPV6_PEERDNS=yes
IPV6_PEERROUTES=yes
Up / down the interface.
[root@centos network-scripts]# nmcli connection down ens82 && nmcli connection u p ens82
Connection 'ens82' successfully deactivated (D-Bus active path: /org/freedesktop /NetworkManager/ActiveConnection/1158)
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkMa nager/ActiveConnection/1162)
[root@centos network-scripts]# nmcli connection down ens92 && nmcli connection u p ens92
Connection 'ens92' successfully deactivated (D-Bus active path: /org/freedesktop /NetworkManager/ActiveConnection/1156)
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkMa nager/ActiveConnection/1163)
The change of IP address was reflected.
[root@centos network-scripts]# ip add
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
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: ens192: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 100 0
link/ether 00:50:56:86:99:7a brd ff:ff:ff:ff:ff:ff
inet 172.22.2.102/16 brd 172.22.255.255 scope global ens192
valid_lft forever preferred_lft forever
inet6 fe80::608f:5a80:8910:3594/64 scope link
valid_lft forever preferred_lft forever
3: ens224: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 100 0
link/ether 00:50:56:86:20:c8 brd ff:ff:ff:ff:ff:ff
inet 10.1.82.102/24 brd 10.1.82.255 scope global ens224
valid_lft forever preferred_lft forever
inet6 fe80::549c:63a:2c22:8109/64 scope link
valid_lft forever preferred_lft forever
4: ens256: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 100 0
link/ether 00:50:56:86:82:06 brd ff:ff:ff:ff:ff:ff
inet 10.1.92.102/24 brd 10.1.92.255 scope global ens256
valid_lft forever preferred_lft forever
inet6 fe80::511d:7bfc:90d2:8df8/64 scope link
valid_lft forever preferred_lft forever
[root@centos network-scripts]#
Device confirmation
nmcli device
Interface enablement
nmcli c m eth224 connection.autoconnect yes
IP address setting
nmcli c m ens81 ipv4.method manual ipv4.addr 10.1.81.102/24 10.1.81.21
Device name change
nmcli connection modify "Wired connection 2" connection.id ens91
Location of interface configuration file
cd /etc/sysconfig/network-scripts
reference: After adding the Network Adapter in the RHEL 7.x VM.
I was addicted to the network not being connected when rebooting centos7