Why is there no access to the local network and the Internet in Ubuntu?

Question

ubuntu

The PC has two operating systems: Ubuntu 12.04 LTS and Windows. In the first, after some time, it seems that some kind of firewall blocks any network activity (pings do not even go to the router) or something is wrong with the routes. There are no problems under Windows. I am superficially familiar with Linux, I really do not want to reinstall, namely to solve the problem. The PC has two network cards (integrated into the motherboard and pci) and wifi (also pci).
I reset the iptables settings according to this manual, I also attach the logs. If you need anything else - write.

[email protected]:~$ netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
0.0.0.0         192.168.0.1     0.0.0.0         UG        0 0          0 eth1
169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 eth1
192.168.0.1     0.0.0.0         255.255.255.255 UH        0 0          0 eth1

[email protected]:~# lspci -nn | grep 0200
04:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 02)
05:01.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ [10ec:8139] (rev 10)

[email protected]:~# dmesg | grep 816
[    0.128160] bio: create slab <bio-0> at 0
[    0.128160] ACPI: Added _OSI(Module Device)
[    0.128160] ACPI: Added _OSI(Processor Device)
[    0.128160] ACPI: Added _OSI(3.0 _SCP Extensions)
[    0.128160] ACPI: Added _OSI(Processor Aggregator Device)
[    0.141173] pci 0000:04:00.0: [10ec:8168] type 00 class 0x020000
[    1.581946] r8169 Gigabit Ethernet driver 2.3LK-NAPI loaded
[    1.582153] r8169 0000:04:00.0: irq 44 for MSI/MSI-X
[    1.582336] r8169 0000:04:00.0 eth0: RTL8168c/8111c at 0xffffc90000c5e000, 00:1f:d0:98:bb:69, XID 1c4000c0 IRQ 44
[    1.582340] r8169 0000:04:00.0 eth0: jumbo features [frames: 6128 bytes, tx checksumming: ko]
[   14.823816] ieee80211 phy0: Selected rate control algorithm 'minstrel_ht'
[   28.105311] r8169 0000:04:00.0 eth0: link down

[email protected]:~# ufw status
Status: inactive

PS Before the "breakdown" I collected Allegro and ClanLib from the source code , I did not go deep into the system.

Answer 1

You have not assigned an IP to any network interface, of course the computer does not see the network. If the NetworkManager applet is installed, then configure it through it, if not, see the /etc/network/interfaces file