Вот такой диалог

user@user-desktop:~$ poff dsl-provider ifdown eth0 ifup eth0
/usr/bin/poff: /bin/kill failed. None stopped.
user@user-desktop:~$ poff dsl-provider ifdown eth0 ifup eth0
/usr/bin/poff: /bin/kill failed. None stopped.
user@user-desktop:~$ cat /etc/network/interfaces
auto lo
iface lo inet loopback
auto dsl-provider
iface dsl-provider inet ppp
pre-up /sbin/ifconfig usb0 up # line maintained by pppoeconf
provider dsl-provider
auto usb0
iface usb0 inet manual
iface ppp0 inet ppp
provider ppp0
auto ppp0
iface eth0 inet dhcp
auto eth0
user@user-desktop:~$ ifconfig
eth0 Link encap:Ethernet HWaddr 00:1e:8c:c3:7a:42
inet6 addr: fe80::21e:8cff:fec3:7a42/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:81 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:9327 (9.1 KB)
Interrupt:18
eth0:avahi Link encap:Ethernet HWaddr 00:1e:8c:c3:7a:42
inet addr:169.254.6.178 Bcast:169.254.255.255 Mask:255.255.0.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Interrupt:18
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:3133 errors:0 dropped:0 overruns:0 frame:0
TX packets:3133 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:160980 (157.2 KB) TX bytes:160980 (157.2 KB)
usb0 Link encap:Ethernet HWaddr 22:17:31:fb:ca:a5
inet6 addr: fe80::2017:31ff:fefb:caa5/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:100 errors:0 dropped:0 overruns:0 frame:0
TX packets:91 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:4627 (4.5 KB) TX bytes:3888 (3.7 KB)
user@user-desktop:~$ cat/etc/resolv.conf
bash: cat/etc/resolv.conf: No such file or directory