Complementando as informações, conforme solicitado:
Mundivox é um serviço de acesso a cabo no centro do Rio de Janeiro. Estou utilizando uma só máquina. Todos IP's são indicados pela operadora do serviço como a configuração necessária e que já funciona no Windows.
Os resultados dos comandos indicados:
~$ ifconfig
eth0 Link encap:Ethernet Endereço de HW 00:16:76:dc:7e:e2
inet end.: 192.168.0.1 Bcast:192.168.0.255 Masc:255.255.255.0
endereço inet6: fe80::216:76ff:fedc:7ee2/64 Escopo:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Métrica:1
pacotes RX:8 erros:0 descartados:0 excesso:0 quadro:0
Pacotes TX:24 erros:0 descartados:0 excesso:0 portadora:0
colisões:0 txqueuelen:1000
RX bytes:902 (902.0 B) TX bytes:4076 (4.0 KB)
IRQ:21 Endereço de E/S:0xde00
lo Link encap:Loopback Local
inet end.: 127.0.0.1 Masc:255.0.0.0
endereço inet6: ::1/128 Escopo:Máquina
UP LOOPBACK RUNNING MTU:16436 Métrica:1
pacotes RX:0 erros:0 descartados:0 excesso:0 quadro:0
Pacotes TX:0 erros:0 descartados:0 excesso:0 portadora:0
colisões:0 txqueuelen:0
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
~$ lspci -v
00:00.0 Host bridge: ATI Technologies Inc Radeon Xpress 200 Host Bridge (rev 01)
Subsystem: Intel Corporation Device d600
Flags: bus master, 66MHz, medium devsel, latency 64
Memory at <ignored> (64-bit, non-prefetchable)
Kernel modules: ati-agp
00:01.0 PCI bridge: ATI Technologies Inc RS480 PCI Bridge
Flags: bus master, 66MHz, medium devsel, latency 99
Bus: primary=00, secondary=01, subordinate=01, sec-latency=68
I/O behind bridge: 0000e000-0000efff
Memory behind bridge: fde00000-fdefffff
Prefetchable memory behind bridge: f0000000-f7ffffff
Capabilities: <access denied>
Kernel modules: shpchp
00:11.0 IDE interface: ATI Technologies Inc IXP SB400 Serial ATA Controller (rev 80) (prog-if 8f [Master SecP SecO PriP PriO])
Subsystem: Intel Corporation Device d600
Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 23
I/O ports at ff00 [size=8]
I/O ports at fe00
I/O ports at fd00 [size=8]
I/O ports at fc00
I/O ports at fb00 [size=16]
Memory at fe02f000 (32-bit, non-prefetchable) [size=512]
Expansion ROM at fdf80000 [disabled] [size=512K]
Capabilities: <access denied>
Kernel driver in use: sata_sil
00:12.0 IDE interface: ATI Technologies Inc IXP SB400 Serial ATA Controller (rev 80) (prog-if 8f [Master SecP SecO PriP PriO])
Subsystem: Intel Corporation Device d600
Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 22
I/O ports at fa00 [size=8]
I/O ports at f900
I/O ports at f800 [size=8]
I/O ports at f700
I/O ports at f600 [size=16]
Memory at fe02e000 (32-bit, non-prefetchable) [size=512]
Expansion ROM at 80000000 [disabled] [size=512K]
Capabilities: <access denied>
Kernel driver in use: sata_sil
00:13.0 USB Controller: ATI Technologies Inc IXP SB400 USB Host Controller (rev 80) (prog-if 10)
Subsystem: Intel Corporation Device d600
Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 19
Memory at fe02d000 (32-bit, non-prefetchable) [size=4K]
Capabilities: <access denied>
Kernel driver in use: ohci_hcd
00:13.1 USB Controller: ATI Technologies Inc IXP SB400 USB Host Controller (rev 80) (prog-if 10)
Subsystem: Intel Corporation Device d600
Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 19
Memory at fe02c000 (32-bit, non-prefetchable) [size=4K]
Capabilities: <access denied>
Kernel driver in use: ohci_hcd
00:13.2 USB Controller: ATI Technologies Inc IXP SB400 USB2 Host Controller (rev 80) (prog-if 20)
Subsystem: Intel Corporation Device d600
Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 19
Memory at fe02b000 (32-bit, non-prefetchable) [size=4K]
Capabilities: <access denied>
Kernel driver in use: ehci_hcd
00:14.0 SMBus: ATI Technologies Inc IXP SB400 SMBus Controller (rev 82)
Subsystem: Intel Corporation Device d600
Flags: 66MHz, medium devsel
I/O ports at 0b00 [size=16]
Memory at fe02a000 (32-bit, non-prefetchable) [size=1K]
Kernel driver in use: piix4_smbus
Kernel modules: i2c-piix4
00:14.1 IDE interface: ATI Technologies Inc IXP SB400 IDE Controller (rev 80) (prog-if 8a [Master SecP PriP])
Subsystem: Intel Corporation Device d600
Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 16
I/O ports at 01f0 [size=8]
I/O ports at 03f4
I/O ports at 0170 [size=8]
I/O ports at 0374
I/O ports at f400 [size=16]
Capabilities: <access denied>
Kernel driver in use: pata_atiixp
00:14.2 Audio device: ATI Technologies Inc IXP SB4x0 High Definition Audio Controller (rev 01)
Subsystem: Intel Corporation Device d600
Flags: bus master, slow devsel, latency 64, IRQ 16
Memory at fe024000 (64-bit, non-prefetchable) [size=16K]
Capabilities: <access denied>
Kernel driver in use: HDA Intel
Kernel modules: snd-hda-intel
00:14.3 ISA bridge: ATI Technologies Inc IXP SB400 PCI-ISA Bridge (rev 80)
Subsystem: Intel Corporation Device d600
Flags: bus master, 66MHz, medium devsel, latency 0
00:14.4 PCI bridge: ATI Technologies Inc IXP SB400 PCI-PCI Bridge (rev 80) (prog-if 01)
Flags: bus master, VGA palette snoop, 66MHz, medium devsel, latency 64
Bus: primary=00, secondary=02, subordinate=02, sec-latency=64
I/O behind bridge: 0000d000-0000dfff
Memory behind bridge: fdd00000-fddfffff
Prefetchable memory behind bridge: fdc00000-fdcfffff
01:05.0 VGA compatible controller: ATI Technologies Inc RC410 [Radeon Xpress 200]
Subsystem: Intel Corporation Device d600
Flags: bus master, 66MHz, medium devsel, latency 64, IRQ 17
Memory at f0000000 (32-bit, prefetchable) [size=128M]
I/O ports at ee00 [size=256]
Memory at fdef0000 (32-bit, non-prefetchable) [size=64K]
[virtual] Expansion ROM at fde00000 [disabled] [size=128K]
Capabilities: <access denied>
02:02.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ (rev 10)
Subsystem: Intel Corporation Device d600
Flags: bus master, medium devsel, latency 64, IRQ 21
I/O ports at de00 [size=256]
Memory at fddff000 (32-bit, non-prefetchable) [size=256]
Capabilities: <access denied>
Kernel driver in use: 8139too
Kernel modules: 8139too, 8139cp
~$