Linux Network

See Linux Tips
Network
ethtool eth0  - Display info on network device
ifdown eth0  - Shutdown network device
ifup eth0  - Startup network device
lsof -i - Show all listening ports(Linux)
mii-tool -F 100basetx-fd
ping -sv mymachine -   Ping hosts (Unix)

Linux dhcp/static network configuration
[/etc/sysconfig/network-scripts/ifcfg-eth0]
  [DHCP]
    DEVICE=eth0
    BOOTPROTO=dhcp
    HWADDR=00:0C:29:74:7E:1D
    ONBOOT=yes
    TYPE=Ethernet
  	DEVICE=eth0
  [STATIC]
    BOOTPROTO=static
    HWADDR=00:0c:29:39:94:25
    ONBOOT=yes
    TYPE=Ethernet
    USERCTL=no
    PEERDNS=yes
    IPV6INIT=no
    NETMASK=255.255.255.0
    IPADDR=172.18.20.68