Kubuntu 24.04 Wired Connection Not Connected: Troubleshooting Guide
In this article, we'll cover the steps to troubleshoot a Kubuntu 24.04 system where the wired connection is not working, while the wireless connection is still active. This scenario can occur when the wired connection is the main connection, and the wireless connection is used to share the internet as a hotspot.
1. Check the Wired Connection Settings
First, it's important to verify that the wired connection is properly configured. To do this, open the Kubuntu network settings by clicking on the network icon in the system tray, then selecting "Network Settings". From there, select the wired connection and make sure it is enabled.
# nmcli connection show "Wired Connection"
connection.uuid: 9b36dcdc-837f-4da1-a46f-a8e2f54645ab
connection.interface-name: enp0s3
connection.type: 802-3-ethernet
connection.autoconnect: yes
connection.autoconnect-priority: -999
connection.id: Wired Connection
connection.timestamp: 1643328334
connection.read-only: no
802-3-ethernet.pairwise-cipher: ccmp
802-3-ethernet.group-cipher: ccmp
802-3-ethernet.key-mgmt: wpa-psk
802-3-ethernet.wpa-group-rekey: 86400
802-3-ethernet.wpa-group-rekey-interval: 0
802-3-ethernet.wpa-pairwise-rekey: 43200
802-3-ethernet.wpa-pairwise-rekey-interval: 0
802-3-ethernet.mtu: auto
802-3-ethernet.s390-subchannels: ""
802-3-ethernet.s390-nettype: ""
802-3-ethernet.s390-options: ""
802-3-ethernet.peer-dhcp: yes
802-3-ethernet.dhcp-client-id: 00:0c:29:5f:5f:da:5e:2d:37:f8
802-3-ethernet.dhcp-hostname: antonio-lenovo
802-3-ethernet.dhcp-timeout: 30
802-3-ethernet.dhcp-send-hostname: yes
802-3-ethernet.dhcp-confirm-price: no
802-3-ethernet.dhcp-ignore-flags: --
802-3-ethernet.dhcp-no-ipv6: no
802-3-ethernet.dhcp-vendor-class-identifier: ""
802-3-ethernet.ip-address: 192.168.2.114/24
802-3-ethernet.ip6-address: ""
802-3-ethernet.ip6-privacy: 0
802-3-ethernet.may-fail: false
802-3-ethernet.dad-timeout: 5
route.route: -
route.gateway: 192.168.2.1
route.metric: -1
route.table: main
route.priority: 0
route6.route: -
route6.gateway: ""
route6.metric: -1
route6.table: main
route6.priority: 0
timeout.link-timeout: 0
timeout.delay-timeout: 5
timeout.dhcp-timeout: 0
timeout.dhcp-information-timeout: 0
timeout.dhcp-exit-timeout: 0
timeout.timeout: 0
timeout.port-timeout: 0
interface-name: enp0s3
type: 802-3-ethernet
autoconnect: yes
permissions:
timestamp: 1643328334
2. Check the Cable Connection
It's possible that the wired connection is not working because the cable is not properly connected, check the cable and make sure it's securely plugged into both the computer and the router/switch.
3. Check the Router/Switch Configuration
It's also possible that the router/switch is not configured to allow the wired connection. Verify that the router/switch is configured to allow the wired connection and that the computer's MAC address is registered in the router/switch if necessary.
4. Check the DNS Settings
In some cases, the wired connection may not be working because of a DNS issue. To check this, run the following command:
# nmcli device show "Wired Connection" | grep IP4.DNS
IP4.DNS[1]: 8.8.8.8
IP4.DNS[2]: 8.8.4.4
If the DNS servers are not set or are incorrect, you can update them using the Network Manager or by editing the /etc/network/interfaces file.
5. Check the Network Interface
The wired connection may also not be working because of a problem with the network interface. To check this, run the following command:
# ethtool enp0s3
Settings for enp0s3:
Supported ports: [ TP ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Half 1000baseT/Full
Supported pause frame use: No
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Half 1000baseT/Full
Advertised pause frame use: No
Advertised auto-negotiation: Yes
Speed: 100Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 1
Transceiver: internal
Auto-negotiation: on
MDI-X: Unknown
Supports Wake-on: g
Wake-on: g
Link detected: no
If the link is not detected, it's possible that there is a hardware issue with the network interface or that the network interface is disabled.
6. Disable and Enable the Wired Connection
Sometimes, disabling and re-enabling the wired connection can solve the issue. To do this, open the Kubuntu network settings, select the wired connection and click on the "Disconnect" button, then wait for a few seconds and click on the "Connect" button.
7. Restart the Network Manager
If the above steps don't work, you can try restarting the Network Manager service. To do this, run the following command:
# systemctl restart NetworkManager
Summary
- References:
- Ubuntu Server Guide - Network Configuration
- Ubuntu Community Help - Networking
- Ubuntu Wiki - Network Manager
In this article, we covered the steps to troubleshoot a Kubuntu 24.04 system where the wired connection is not working, while the wireless connection is still active. This scenario can occur when the wired connection is the main connection, and the wireless connection is used to share the internet as a hotspot. We hope that this troubleshooting guide will help you resolve the issue and get your wired connection working again.