Salve guru e ben ritrovati
Problema del giorno (mai farsene mancare uno!)

- realizzata rete Lan per portare collegamento internet in altra mia postazione (7km)
- pc all'arrivo (dual boot win xp - Ubuntu 12.10) destinato solo alla LAN (ovviamente solo Ubu!!)
- primi due mesi funzionamento regolare
- da qualche giorno continue sconnessioni, sempre più frequenti;
- verificati, nell'ordine: router, lan ed ISP;
- router e lan OK; verifica dell'ISP (h24) non ha evidenziato problemi;

supposti problemi alla di scheda di rete ho eseguito test di sistema che indica “stato device disattivato" – pur non comprendendo come potesse funzionare ugualmente – ho attivato e rieffettuato il test:

networking/detect
Devices found by lspci--Ethernet: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller (rev 01)
Devices found by Network Manager--Type: Ethernet Interface: eth0 IP: 192.168.1.2 Driver: r8169 (ver: 2.3LK-NAPI) State: Activated
networking/internet
nessuna connessione ad internet ma io sono! connesso!!!

sudo lshw -C network
*-network
description: Ethernet interface
product: RTL8101E/RTL8102E PCI Express Fast Ethernet controller
vendor: Realtek Semiconductor Co., Ltd.
physical id: 0
bus info: pci@0000:01:00.0
logical name: eth0
version: 01
serial: 00:19:66:67:0f:3b
size: 100Mbit/s
capacity: 100Mbit/s
width: 64 bits
clock: 33MHz
capabilities: pm vpd msi pciexpress bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full ip=192.168.1.2 latency=0 link=yes multicast=yes port=MII speed=100Mbit/s
resources: irq:40 ioport:c800(size=256) memory:fdfff000-fdffffff memory:fdfc0000-fdfdffff

rfkill list (non funge)

Dmesg
.....
[ 0.826165] r8169 Gigabit Ethernet driver 2.3LK-NAPI loaded
[ 0.826308] r8169 0000:01:00.0: irq 40 for MSI/MSI-X
[ 0.826541] r8169 0000:01:00.0: eth0: RTL8101e at 0xf8410000, 00:19:66:67:0f:3b, XID 94200000 IRQ 40

[ 21.371214] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 21.391039] udevd[452]: starting version 175
[ 21.440508] lp: driver loaded but no devices found
[ 21.569015] EXT4-fs (sda3): re-mounted. Opts: errors=remount-ro
[ 21.756948] intel_rng: FWH not detected

[ 21.809169] ACPI Warning: 0x00000830-0x00000833 SystemIO conflicts with Region \_SB_.PCI0.SBRG.SMIE 1 (20120320/utaddress-251)
[ 21.809179] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver
[ 21.809182] lpc_ich: Resource conflict(s) found affecting iTCO_wdt
[ 21.809191] ACPI Warning: 0x00000480-0x000004bf SystemIO conflicts with Region \GPRG 1 (20120320/utaddress-251)
[ 21.809197] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver
[ 21.809199] lpc_ich: Resource conflict(s) found affecting gpio_ich

[ 21.861521] lp0: using parport0 (interrupt-driven).

[ 22.622703] r8169 0000:01:00.0: eth0: link down
[ 22.622727] r8169 0000:01:00.0: eth0: link down

[ 22.629880] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 22.630450] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready
[ 22.690510] microcode: CPU1 sig=0x6fd, pf=0x1, revision=0xa1
[ 22.693249] microcode: Microcode Update Driver: v2.00 <tigran@aivazian.fsnet.co.uk>, Peter Oruba
[ 22.888732] init: gdm main process (1153) killed by TERM signal
[ 23.320906] input: ImExPS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input10
[ 24.158355] init: plymouth-stop pre-start process (1571) terminated with status 1
[ 24.242220] r8169 0000:01:00.0: eth0: link up
[ 24.242409] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready

ifconfig
eth0 Link encap:Ethernet IndirizzoHW 00:19:66:67:0f:3b
indirizzo inet:192.168.1.2
Bcast: 192.168.1.255
Maschera: 255.255.255.0
indirizzo inet6: fe80::219:66ff:fe67:f3b/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:5437 errors:0 dropped:1 overruns:0 frame:0
TX packets:8791 errors:0 dropped:0 overruns:0 carrier:0
collisioni:0 txqueuelen:1000
Byte RX:1306286 (1.3 MB) Byte TX:1534280 (1.5 MB)

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:2250 errors:0 dropped:0 overruns:0 frame:0
TX packets:2250 errors:0 dropped:0 overruns:0 carrier:0
collisioni: 0 txqueuelen:0
Byte RX: 190321(190.3 KB)
Byte TX: 190321 (190.3 KB)

cat /etc/resolv.conf
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN nameserver 127.0.1.1

Su altri due pc le sconnessioni non avvengomo!!!!

Grazie anticipate e scutemi la lunghezza del post.