Thread: wired connection disconnected

my network connection periodically comes , goes on dual boot ubuntu 12.04 / windows 7 64 bit system. happens ubuntu. doesn't happen windows 7 loaded. also, have 5 other computers on network, 4 of dual boot windows 7/ubuntu 12.04. problem not observed on other machine.

upgraded 12.04 morning fresh installation after deleting old partition , formatting new one. initially, network connection established , worked fine. while reloading files backup network went down. after poking @ several times ifconfig, ifup, ifdown dhclient , nm-tool, came , continued work 15 minutes went down again.

sudo ifdown eth0 returns "interface eth0 not configured"

sudo ifup eth0 returns "ignoring unknown interface eth0"

ifconfig shows hardware correct mac address no ip address

nm-tool shows device wired driver r8169, correct mac address, carrier detected , on, speed 100 mb/s, state="connecting (getting ip configuration)

dmesg says nothing network going down repeated reports no ipv6 router present.

have deleted, added, , reconfigured network connections parameters @ least dozen times using small no-name applet in notifications panel.

when ping router returns "network unreachable".

@ point, cannot network @ all. can help?

please show outputs of:

code:

lspci -nnk | grep -ia2 net  lsmod

checked bios ("last state", "on")?

Forum The Ubuntu Forum Community Ubuntu Official Flavours Support Networking & Wireless [ubuntu] wired connection disconnected

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