Dreamplug, IF IP GONE.

Create a network config file manually.
# vi /etc/network/interfaces
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address 192.168.1.1
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255

auto eth1
iface eth1 inet static
address 192.168.2.1
netmask 255.255.255.0
network 192.168.2.0
broadcast 192.168.2.255
# /sbin/ifup -a
Note-01:
# ifup -h

BusyBox v1.16.1 (2015-12-03 19:06:58 CST) multi-call binary.

Usage: ifup [-ainmvf] IFACE...

Options:
        -a      De/configure all interfaces automatically
        -i FILE Use FILE for interface definitions
        -n      Print out what would happen, but don't do it
                (note: doesn't disable mappings)
        -m      Don't run any mappings
        -v      Print out what would happen before doing it
        -f      Force de/configuration

Note-02: When "ifup -a" and get below message, try this

ifup: interface lo already configured
ifup: interface eth0 already configured
ifup: interface eth1 already configured

# ifdown -a
# ifup -a

Dreamplug, uDHCPd options

File: /etc/udhcpd.conf

# Sample udhcpd configuration file (/etc/udhcpd.conf)
# Values shown are defaults

# The start and end of the IP lease block
start  192.168.0.20
end  192.168.0.254

# The interface that udhcpd will use
interface eth0

Dreamplug, DHCP server