Reload ethernet card configuration

Use /etc/init.d instead of service since the latter is deprecated.

_$: /etc/init.d/networking restart

Alternatively:

_$: ifdown -a && ifup -a

When connected to a server and you do not want to lose the connection:

_$: nohup sh -c "ifdown eth0 && ifup eth0"

Change ethernet card speed

Check current speed

_$: ethtool eth0
Settings for eth0:
	Supported ports: [ TP ]
	Supported link modes:   10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Half 1000baseT/Full	# <--- Total capacity
	Supported pause frame use: No
	Supports auto-negotiation: Yes
	Advertised link modes:  10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Half 1000baseT/Full
	Advertised pause frame use: Symmetric
	Advertised auto-negotiation: Yes
	Link partner advertised link modes:  10baseT/Half 10baseT/Full
	                                     100baseT/Half 100baseT/Full
	Link partner advertised pause frame use: Symmetric
	Link partner advertised auto-negotiation: Yes
	Speed: 100Mb/s     # <--- Current speed
	Duplex: Full
	Port: Twisted Pair
	PHYAD: 1
	Transceiver: internal
	Auto-negotiation: on
	MDI-X: off
	Supports Wake-on: g
	Wake-on: g
	Current message level: 0x000000ff (255)
			       drv probe link timer ifdown ifup rx_err tx_err
	Link detected: yes

_$: lshw -C network
PCI (sysfs)
  *-network
       description: Ethernet interface
       product: NetXtreme BCM5722 Gigabit Ethernet PCI Express
       vendor: Broadcom Corporation
       physical id: 0
       bus info: pci@0000:0e:00.0
       logical name: eth0
       version: 00
       serial: 00:23:7d:07:f0:72
       size: 100Mbit/s      # <--- Current speed
       capacity: 1Gbit/s    # <--- Total capacity
       width: 64 bits
       clock: 33MHz
       capabilities: pm vpd msi pciexpress bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=tg3 driverversion=3.128 duplex=full firmware=5722-v3.07 ip=192.168.1.101 latency=0 link=yes multicast=yes port=twisted pair speed=100Mbit/s
       resources: irq:46 memory:ed000000-ed00ffff

Change speed

_$: ethtool -s eth0 speed 1000 duplex full

Check new speed

_$: ethtool eth0
Settings for eth0:
	Supported ports: [ TP ]
	Supported link modes:   10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Half 1000baseT/Full # <--- Total capacity
	Supported pause frame use: No
	Supports auto-negotiation: Yes
	Advertised link modes:  1000baseT/Full
	Advertised pause frame use: Symmetric
	Advertised auto-negotiation: Yes
	Link partner advertised link modes:  10baseT/Half 10baseT/Full
	                                     100baseT/Half 100baseT/Full
	                                     1000baseT/Half 1000baseT/Full
	Link partner advertised pause frame use: Symmetric
	Link partner advertised auto-negotiation: Yes
	Speed: 1000Mb/s    # <--- New speed
	Duplex: Full
	Port: Twisted Pair
	PHYAD: 1
	Transceiver: internal
	Auto-negotiation: on
	MDI-X: off
	Supports Wake-on: g
	Wake-on: g
	Current message level: 0x000000ff (255)
			       drv probe link timer ifdown ifup rx_err tx_err
	Link detected: yes

_$: lshw -C network
PCI (sysfs)
  *-network
       description: Ethernet interface
       product: NetXtreme BCM5722 Gigabit Ethernet PCI Express
       vendor: Broadcom Corporation
       physical id: 0
       bus info: pci@0000:0e:00.0
       logical name: eth0
       version: 00
       serial: 00:23:7d:07:f0:72
       size: 1Gbit/s        # <--- New speed
       capacity: 1Gbit/s    # <--- Total capacity
       width: 64 bits
       clock: 33MHz
       capabilities: pm vpd msi pciexpress bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=tg3 driverversion=3.128 duplex=full firmware=5722-v3.07 ip=192.168.1.101 latency=0 link=yes multicast=yes port=twisted pair speed=1Gbit/s
       resources: irq:46 memory:ed000000-ed00ffff