¿Por qué mi conexión Ethernet se conecta y desconecta repetidamente?

Solo trato de hacer que mi conexión Ethernet funcione en Oneiric, y cuando conecto el cable, se conecta y se desconecta para siempre. / var / syslog dice esto (lo repite una y otra vez):

Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Activation (eth0) successful, device activated. Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 5 of 5 (IP Configure Commit) complete. Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 4 of 5 (IP4 Configure Get) complete. Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  dnsmasq exited with error: Network access problem (address in use; permissions; etc) (2) Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  (eth0): device state change: activated -> failed (reason 'sharing-start-failed') [100 120 18] Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Activation (eth0) failed. Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  (eth0): device state change: failed -> disconnected (reason 'none') [120 30 0] Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  (eth0): deactivating device (reason 'none') [0] Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Withdrawing address record for 10.42.43.1 on eth0. Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Leaving mDNS multicast group on interface eth0.IPv4 with address 10.42.43.1. Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Interface eth0.IPv4 no longer relevant for mDNS. Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Clearing nscd hosts cache. Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table nat --delete POSTROUTING --source 10.42.43.0/255.255.255.0 ! --destination 10.42.43.0/255.255.255.0 --jump MASQUERADE Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --delete FORWARD --destination 10.42.43.0/255.255.255.0 --out-interface eth0 --match state --state ESTABLISHED,RELATED --jump ACCEPT Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --delete FORWARD --source 10.42.43.0/255.255.255.0 --in-interface eth0 --jump ACCEPT Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --delete FORWARD --in-interface eth0 --out-interface eth0 --jump ACCEPT Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --delete FORWARD --out-interface eth0 --jump REJECT Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --delete FORWARD --in-interface eth0 --jump REJECT Sep 26 17:06:47 X58A-UD3R ntpdate[15004]: Can't find host ntp.ubuntu.com: Name or service not known (-2) Sep 26 17:06:47 X58A-UD3R ntpdate[15004]: no servers can be used, exiting Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --delete INPUT --in-interface eth0 --protocol udp --destination-port 67 --jump ACCEPT Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --delete INPUT --in-interface eth0 --protocol tcp --destination-port 67 --jump ACCEPT Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --delete INPUT --in-interface eth0 --protocol udp --destination-port 53 --jump ACCEPT Sep 26 17:06:47 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --delete INPUT --in-interface eth0 --protocol tcp --destination-port 53 --jump ACCEPT Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::a800:4ff:fe00:a04. Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: New relevant interface eth0.IPv6 for mDNS. Sep 26 17:06:47 X58A-UD3R avahi-daemon[1321]: Registering new address record for fe80::a800:4ff:fe00:a04 on eth0.*. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Auto-activating connection 'Wired'. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) starting connection 'Wired' Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0] Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled... Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 1 of 5 (Device Prepare) started... Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 2 of 5 (Device Configure) scheduled... Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 1 of 5 (Device Prepare) complete. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 2 of 5 (Device Configure) starting... Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  (eth0): device state change: prepare -> config (reason 'none') [40 50 0] Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 2 of 5 (Device Configure) successful. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 2 of 5 (Device Configure) complete. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 3 of 5 (IP Configure Start) started... Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  (eth0): device state change: config -> ip-config (reason 'none') [50 70 0] Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 4 of 5 (IP4 Configure Get) scheduled... Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Beginning IP6 addrconf. Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Withdrawing address record for fe80::a800:4ff:fe00:a04 on eth0. Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::a800:4ff:fe00:a04. Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Interface eth0.IPv6 no longer relevant for mDNS. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 3 of 5 (IP Configure Start) complete. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 4 of 5 (IP4 Configure Get) started... Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Activation (eth0) Stage 5 of 5 (IP Configure Commit) started... Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Joining mDNS multicast group on interface eth0.IPv4 with address 10.42.43.1. Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: New relevant interface eth0.IPv4 for mDNS. Sep 26 17:06:50 X58A-UD3R avahi-daemon[1321]: Registering new address record for 10.42.43.1 on eth0.IPv4. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  caught signal 15, shutting down normally. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Clearing nscd hosts cache. Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --insert INPUT --in-interface eth0 --protocol tcp --destination-port 53 --jump ACCEPT Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --insert INPUT --in-interface eth0 --protocol udp --destination-port 53 --jump ACCEPT Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --insert INPUT --in-interface eth0 --protocol tcp --destination-port 67 --jump ACCEPT Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --insert INPUT --in-interface eth0 --protocol udp --destination-port 67 --jump ACCEPT Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --insert FORWARD --in-interface eth0 --jump REJECT Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --insert FORWARD --out-interface eth0 --jump REJECT Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --insert FORWARD --in-interface eth0 --out-interface eth0 --jump ACCEPT Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --insert FORWARD --source 10.42.43.0/255.255.255.0 --in-interface eth0 --jump ACCEPT Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table filter --insert FORWARD --destination 10.42.43.0/255.255.255.0 --out-interface eth0 --match state --state ESTABLISHED,RELATED --jump ACCEPT Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Executing: /sbin/iptables --table nat --insert POSTROUTING --source 10.42.43.0/255.255.255.0 ! --destination 10.42.43.0/255.255.255.0 --jump MASQUERADE Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  Starting dnsmasq... Sep 26 17:06:50 X58A-UD3R NetworkManager[1344]:  (eth0): device state change: ip-config -> activated (reason 'none') [70 100 0] Sep 26 17:06:50 X58A-UD3R dnsmasq[15064]: failed to create listening socket for 10.42.43.1: Address already in use Sep 26 17:06:50 X58A-UD3R dnsmasq[15064]: FAILED to start up 

corríjame si estoy equivocado, pero parece que está intentando usar una conexión compartida. Hay un error en Oneiric con respecto a esto. Por favor, busque una respuesta diferente para una solución y el enlace al error. La conexión por cable compartida con otras computadoras se conecta y luego se desconecta en el applet de nm. La solución es configurar IPv6 para que se ignore cuando edite la conexión y luego haga sudo killall dnsmasq

Lo mismo sucede cuando trato de compartir Internet inalámbrica ad hoc en Ubuntu11.10 sudo killall dnsmasq ha ayudado finalmente.

Diagnostique el controlador haciendo clic en el ícono LAN, abra Compartir en red, haga clic en Conexiones de área local, Diagnosticar.

Lo arreglé para mí. Esto restablecerá el adaptador LAN, por lo que funcionará normalmente.