sudo ethtool eth0
Settings for eth0:
	Supported ports: [ TP ]
	Supported link modes:   10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Supported pause frame use: No
	Supports auto-negotiation: Yes
	Advertised link modes:  10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Advertised pause frame use: No
	Advertised auto-negotiation: Yes
	Speed: 100Mb/s
	Duplex: Full
	Port: Twisted Pair
	PHYAD: 2
	Transceiver: internal
	Auto-negotiation: on
	MDI-X: off
	Supports Wake-on: pumbg
	Wake-on: g
	Current message level: 0x00000001 (1)
			       drv
	Link detected: yes


Dmesg output :

[   20.038502] eth0: no IPv6 routers present
[   77.247735] init: tty1 main process ended, respawning
[23546.565566] ip_tables: (C) 2000-2006 Netfilter Core Team
[23688.978024] e1000e: eth0 NIC Link is Down
[23702.153794] e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: Rx/Tx
[23702.153801] e1000e 0000:00:19.0: eth0: 10/100 speed: disabling TSO
[23761.729950] e1000e: eth0 NIC Link is Down
[23783.255839] e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: Rx/Tx
[23783.255845] e1000e 0000:00:19.0: eth0: 10/100 speed: disabling TSO
[26524.226026] init: vsftpd main process (814) killed by TERM signal
[28388.150293] init: vsftpd main process (2015) killed by TERM signal
[84764.474375] e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: None
[84764.474381] e1000e 0000:00:19.0: eth0: 10/100 speed: disabling TSO
[87228.636324] e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: Rx/Tx
[87228.636330] e1000e 0000:00:19.0: eth0: 10/100 speed: disabling TSO
[88984.425807] e1000e: eth0 NIC Link is Down
[89001.252733] e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: Rx/Tx
[89001.252739] e1000e 0000:00:19.0: eth0: 10/100 speed: disabling TSO