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I have

$ ifconfig
eth0      Link encap:Ethernet  HWaddr 00:1f:d0:99:ea:a9  
          inet addr:  Bcast:  Mask:
          inet6 addr: fe80::21f:d0ff:fe99:eaa9/64 Scope:Link
          RX packets:309399 errors:0 dropped:0 overruns:0 frame:0
          TX packets:262110 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:312968243 (312.9 MB)  TX bytes:35445808 (35.4 MB)

lo        Link encap:Локальная петля (Loopback)  
          inet addr:  Mask:
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:4175 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4175 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:975196 (975.1 KB)  TX bytes:975196 (975.1 KB)


$ cat /etc/network/interfaces 
auto lo
iface lo inet loopback

How ifconfig show me settings for eth0? Where are settings store?

UPD: I do not use NetworkManager, and I have LXDE, not Gnome

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up vote 1 down vote accepted

This is most certainly the NetworkManager which is started after login, not at boot time. Look for the Network icon on the Desktop.

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~/.gconf/system/networking/connections – Thomas Sep 8 '11 at 10:09
Is is possible that NetworkManager is been used without the GUI. Configuratin files for this shoud be here: ~/.gconf/system/networking/connectionsor here: /etc/NetworkManager/system-connections. There are alternatives to NetworkManager tha could be in use, e.g. wicd ( In the end there are several ways to set up a nework interface without using /etc/network/interfaces - as this is obviously a non-standard installation it's more like guessing. – Thomas Sep 8 '11 at 10:15
It's true! [802-3-ethernet] duplex=full mac-address=0:1f:d0:99:ea:a9 [connection] id=Auto eth0 uuid=62a54eb7-a80e-497d-b764-c47a2aeb0ef5 type=802-3-ethernet timestamp=1310648604 [ipv6] method=ignore [ipv4] method=manual dns=; addresses1=;24;; – Guy Fawkes Sep 8 '11 at 11:30

You want to look at /etc/dhcp/dhclient.conf

In mine I get all settings from the DHCP server (on my router) apart from my hostname.

Relevant section

send host-name "<hostname>";
#send dhcp-client-identifier 1:0:a0:24:ab:fb:9c;
#send dhcp-lease-time 3600;
#supersede domain-name "";
#prepend domain-name-servers;
request subnet-mask, broadcast-address, time-offset, routers,
    domain-name, domain-name-servers, domain-search, host-name,
    netbios-name-servers, netbios-scope, interface-mtu,
    rfc3442-classless-static-routes, ntp-servers;
#require subnet-mask, domain-name-servers;
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I suspect this is irrelevant. I have almost the same content (in /etc/dhcp3/dhclient.conf), but the IP address is static, as configured in NetworkManager. – enzotib Sep 7 '11 at 13:22
Yes, I always have, but there are a lot of computers in the network; I think it's impossible always get this IP. – Guy Fawkes Sep 8 '11 at 8:36
No it isn't impossible, you get a lease time on the dhcp server (probably your router), assuming you connect more often that the lease time you will always get the same IP. That is by design. – Richard Holloway Sep 9 '11 at 15:16

I suppose you are using NetworkManager.

That settings are managed by NetworkManager by default, that probably is setup to request values from a DHCP server.

Look for "Auto eth0" connection in NetworkManager.

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AFAIK If you are using network-manager, interfaces are handled by network-manager

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No, I don't use network-manager – Guy Fawkes Sep 8 '11 at 8:41

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