From almost any Linux system you can use "ip" or the ifconfig/route commands to initially set up the network. To configure the network interface manually you can use the same set of commands in the initramfs or Debian.
# Bring up the CPU network interface ifconfig eth0 up # Or if you're on a baseboard with a second ethernet port, you can use that as: ifconfig eth1 up # Set an ip address (assumes 255.255.255.0 subnet mask) ifconfig eth0 192.168.0.50 # Set a specific subnet ifconfig eth0 192.168.0.50 netmask 255.255.0.0 # Configure your route. This is the server that provides your internet connection. route add default gw 192.168.0.1 # Edit /etc/resolv.conf for your DNS server echo "nameserver 192.168.0.1" > /etc/resolv.conf
Most commonly networks will offer DHCP which can be set up with one command:
Configure DHCP in Debian:
# To setup the default CPU ethernet port dhclient eth0 # Or if you're on a baseboard with a second ethernet port, you can use that as: dhclient eth1 # You can configure all ethernet ports for a dhcp response with dhclient
Configure DHCP in the initrd:
udhcpc -i eth0 # Or if you're on a baseboard with a second ethernet port, you can use that as: udhcpc -i eth1
To make your network settings take effect on startup in Debian, edit /etc/network/interfaces:
# Used by ifup(8) and ifdown(8). See the interfaces(5) manpage or # /usr/share/doc/ifupdown/examples for more information. # We always want the loopback interface. # auto lo iface lo inet loopback auto eth0 iface eth0 inet static address 192.168.0.50 netmask 255.255.255.0 gateway 192.168.0.1 auto eth1 iface eth1 inet dhcp
|Note:||During Debian's startup it will assign the interfaces eth0 and eth1 to the detected mac addresses in /etc/udev/rules.d/70-persistent-net.rules. If the system is imaged while this file exists it will assign the new interfaces as eth1 and eth2. This file is generated automatically on startup, and should be removed before your first software image is created. The initrd network configuration does not use this file.|
In this example eth0 is a static configuration and eth1 receives its configuration from the DHCP server. For more information on network configuration in Debian see their documentation here.