It is a strange (for me) and random behaviour. This morning, for example, running Ubuntu for the first time, I found internet connection working perfectly (I could surf and download with no problem at all).
However, after rebooting, net connection was unavailable as usual. Sometimes after running Vista on the same PC, net works, sometimes it doesn't.
This is the result of my test, when net is not working:
$ lspci
00:00.0 Host bridge: Intel Corporation 82G33/G31/P35/P31 Express DRAM Controller (rev 02)
00:01.0 PCI bridge: Intel Corporation 82G33/G31/P35/P31 Express PCI Express Root Port (rev 02)
00:02.0 VGA compatible controller: Intel Corporation 82G33/G31 Express Integrated Graphics Controller (rev 02)
00:19.0 Ethernet controller: Intel Corporation 82562V-2 10/100 Network Connection (rev 02)
00:1a.0 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #4 (rev 02)
00:1a.1 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #5 (rev 02)
00:1a.2 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #6 (rev 02)
00:1a.7 USB Controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #2 (rev 02)
00:1b.0 Audio device: Intel Corporation 82801I (ICH9 Family) HD Audio Controller (rev 02)
00:1d.0 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #1 (rev 02)
00:1d.1 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #2 (rev 02)
00:1d.2 USB Controller: Intel Corporation 82801I (ICH9 Family) USB UHCI Controller #3 (rev 02)
00:1d.7 USB Controller: Intel Corporation 82801I (ICH9 Family) USB2 EHCI Controller #1 (rev 02)
00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev 92)
00:1f.0 ISA bridge: Intel Corporation 82801IR (ICH9R) LPC Interface Controller (rev 02)
00:1f.2 IDE interface: Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 4 port SATA IDE Controller (rev 02)
00:1f.3 SMBus: Intel Corporation 82801I (ICH9 Family) SMBus Controller (rev 02)
00:1f.5 IDE interface: Intel Corporation 82801I (ICH9 Family) 2 port SATA IDE Controller (rev 02)
02:01.0 Communication controller: Conexant Systems, Inc. SoftV92 SpeakerPhone SoftRing Modem with SmartSP (rev 01)
$ sudo ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:21:70:15:f6:cd
indirizzo inet6: fe80::221:70ff:fe15:f6cd/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:36 errors:0 dropped:0 overruns:0 carrier:0
collisioni:0 txqueuelen:100
Byte RX:0 (0.0 B) Byte TX:6128 (6.1 KB)
Memoria:fdfc0000-fdfe0000
eth0:avahi Link encap:Ethernet HWaddr 00:21:70:15:f6:cd
indirizzo inet:169.254.10.26 Bcast:169.254.255.255 Maschera:255.255.0.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
Memoria:fdfc0000-fdfe0000
lo Link encap:Loopback locale
indirizzo inet:127.0.0.1 Maschera:255.0.0.0
indirizzo inet6: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:4 errors:0 dropped:0 overruns:0 frame:0
TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
collisioni:0 txqueuelen:0
Byte RX:240 (240.0 B) Byte TX:240 (240.0 B)
$ ping
www.linuxquestions.org
ping: unknown host
www.libero.it
$ ping 75.126.162.205
connect: Network is unreachable
I use a Belkin modem router. My network manager in Ubuntu is Wicd. Thanks a lot for your kind help!
Giancarlo