You have been subscribed to a public bug: When the Power cable is unplugged, the Internet connection is alredy shown as connected, but it dosn´t funktion. The solution ist to enable the autoneg manually every time after the power cable is unplugged.
sudo ethtool -s eth0 autoneg on The netbook is a Samsung N150 with Ubuntu 12.4 more Information: lspci -nnk | grep -iA2 net 05:00.0 Network controller [0280]: Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express) [168c:002b] (rev 01) Subsystem: Foxconn International, Inc. Device [105b:e025] Kernel driver in use: ath9k -- 09:00.0 Ethernet controller [0200]: Marvell Technology Group Ltd. 88E8040 PCI-E Fast Ethernet Controller [11ab:4354] Subsystem: Samsung Electronics Co Ltd Device [144d:c072] Kernel driver in use: sky2 ifconfig -a eth0 Link encap:Ethernet Hardware Adresse 00:24:54:45:95:95 inet Adresse:10.42.0.1 Bcast:10.42.0.255 Maske:255.255.255.0 inet6-Adresse: fe80::224:54ff:fe45:9595/64 Gültigkeitsbereich:Verbindung UP BROADCAST RUNNING MULTICAST MTU:1500 Metrik:1 RX packets:1149981 errors:0 dropped:0 overruns:0 frame:0 TX packets:1744626 errors:0 dropped:0 overruns:0 carrier:0 Kollisionen:0 Sendewarteschlangenlänge:1000 RX-Bytes:92461226 (92.4 MB) TX-Bytes:2447087681 (2.4 GB) Interrupt:18 sudo ethtool eth0 Settings for eth0: Supported ports: [ TP ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full Supported pause frame use: No Supports auto-negotiation: Yes Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full Advertised pause frame use: No Advertised auto-negotiation: Yes Speed: 100Mb/s Duplex: Full Port: Twisted Pair PHYAD: 0 Transceiver: internal Auto-negotiation: on MDI-X: Unknown Supports Wake-on: pg Wake-on: d Current message level: 0x000000ff (255) drv probe link timer ifdown ifup rx_err tx_err Link detected: yes ** Affects: ubuntu Importance: Undecided Status: New -- No network (eth) in Battery mode https://bugs.launchpad.net/bugs/1053945 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs