Inspecting the Status of Network Links with 'networkctl'

You can inspect information about network connections by using the networkctl command. This can help you configure networking services and troubleshoot networking problems.

You can progressively add options and arguments to the networkctl command to move from general information about network connections to specific information about a network connection.

networkctl Command Without Options

Run the networkctl command without options to default to the list command:

networkctl
IDX LINK             TYPE               OPERATIONAL SETUP
  1 lo               loopback           carrier     unmanaged
  2 eth0             ether              routable    configured
  3 docker0          ether              routable    unmanaged
  11 vethb0aa7a6      ether              degraded    unmanaged
  4 links listed.

‘networkctl status’ Command

Run networkctl with the status command to display the following information:

root@photon-rc [ ~ ]# > networkctl status
   State: routable
  Address: 10.197.103.56 on eno1
           172.17.0.1 on docker0
           fe80::20c:29ff:fe44:f92c on eno1
  Gateway: 10.197.103.253 (Cisco Systems, Inc) on eno1
      DNS: 10.142.7.1
           10.132.7.1
           10.166.17.90
      NTP: 10.128.152.81
           10.166.1.120
           10.188.26.119
           10.84.55.42

You can see that there are active network links with IP addresses for not only the Ethernet connection but also a Docker container.

You can add a network link, such as the Ethernet connection, as the argument of the status command to show specific information about the link:

	root@photon-rc [ ~ ]# networkctl status ens33
	* 2: ens33
	         Link File: /usr/lib/systemd/network/99-default.link                                      
                  Network File: /usr/lib/systemd/network/10-eth.network                                       
                          Type: ether                                                                         
                         State: routable (configured)                               
             Alternative Names: enp2s1                                                                        
                          Path: pci-0000:02:01.0                                                              
                        Driver: e1000                                                                         
                        Vendor: Intel Corporation                                                             
                         Model: 82545EM Gigabit Ethernet Controller (Copper) (PRO/1000 MT Single Port Adapter)
                    HW Address: 00:0c:29:5f:d1:39 (VMware, Inc.)                                              
                           MTU: 1500 (min: 46, max: 16110)                                                    
                         QDisc: fq_codel                                                                      
  IPv6 Address Generation Mode: eui64                                                                         
          Queue Length (Tx/Rx): 1/1                                                                           
              Auto negotiation: yes                                                                           
                         Speed: 1Gbps                                                                         
                        Duplex: full                                                                          
                          Port: tp                                                                            
                       Address: 172.16.85.225 (DHCP4 via 172.16.85.254)                                       
                                fe80::20c:29ff:fe5f:d139                                                      
                       Gateway: 172.16.85.2 (VMware, Inc.)                                                    
                           DNS: 172.16.85.2                                                                   
               DHCP4 Client ID: IAID:0x2b9434c1/DUID                                                          
             DHCP6 Client DUID: DUID-EN/Vendor:0000ab11d258482fc7eee6510000                                   
Feb 26 10:19:44 fedora systemd-networkd[650]: ens33: Link UP
Feb 26 10:19:44 fedora systemd-networkd[650]: ens33: Gained carrier
Feb 26 10:19:45 fedora systemd-networkd[650]: ens33: DHCPv4 address 172.16.85.225/24 via 172.16.85.2
Feb 26 10:19:46 fedora systemd-networkd[650]: ens33: Gained IPv6LL

‘networkctl status’ Command With Docker Option

You can add a Docker container as the argument of the status command to show specific information about the container:

networkctl status docker0
	* 3: docker0
	       Link File: /usr/lib/systemd/network/99-default.link
	    Network File: n/a
	            Type: ether
	           State: routable (unmanaged)
	          Driver: bridge
	      HW Address: 02:42:f0:f7:bd:81
	             MTU: 1500
	         Address: 172.17.0.1
	                  fe80::42:f0ff:fef7:bd81

In the example above, the state of the Docker container is unmanaged because Docker handles managing the networking for the containers without using systemd-resolved or systemd-networkd. Docker manages the container connection by using its bridge drive.

For more information about networkctl commands and options, see https://www.freedesktop.org/software/systemd/man/networkctl.html.

Last modified March 24, 2021: big docs v4 cleanup (80869a1a7)