ipconfig ifconfig

The equivalent of ipconfig command in Linux is ifconfig although you may need to use multiple commands to retrieve and configure network configuration in Linux.  Here are some basic equivalent uses of ipconfig in linux:
ipconfig simply translates to:
$ ifconfig
ipconfig /all could be translated to,
$ ifconfig -a
although it does not show all information as it is in case of ipconfig \all.  -a option in the above example instructs ifconfig to also show all network interfaces even those that are disconnected ( down ) .
ipconfig /renew is used to renew an IP address automatically using DHCP. The closes equivalent to this command dhclient:
# dhclient eth0
dhclient will release IP address for eth0 network interface and obtain new.
ipconfig /release will release current IP address. To release IP address in linux you can use:
# dhclient -r eth0
To release IP address is not required by DHCP protocol. If you want to discard IP address and disable network interface simply use:
# ifconfig eth0 down