NEXPEED NBG440 User’s Manual
NexComm Systems, Inc. 31 PAGE
COMMAND
(conf)# interface <ifname> ip unnumbered
(conf)# interface <ifname> ip <address> <mask>
Parameters
unnumbered : sets IP unnumbered
<ifname> - interface name
<address> - IP address
<mask> - subnet mask
Usage Examples:
(conf)# int s0 ip 192.168.3.2 255.255.255.252
(conf)# int s0 ip unnumbered
Note:
IP Unnumbered
Every interface requires a unique subnet. Although each point-to-point serial connection
has only two end points to address, if we assign an entire subnet to each serial interface
where only two addresses are needed. If we use IP unnumbered on each serial interface,
we save address space; the address of a LAN interface is "borrowed" and used as the
source address for packets sourced from the serial interface. In this way, address space
is conserved. IP unnumbered only makes sense for point-to-point links.
Assigning Multiple IP Addresses to the Interface
The router supports multiple IP addresses per interface. You can specify an unlimited
number of secondary addresses. Secondary IP addresses can be used in a variety of
situations. For example, suppose your subnetting allows up to 254 hosts per logical
subnet, but on one physical subnet you must have 300 host addresses. Using secondary
IP addresses on the routers allows you to have two logical subnets using one physical
subnet.
To assign multiple IP addresses to the interface, use the following command.
COMMAND
(conf)# interface <ifname> ip <address> <mask> secondary
Parameters
<ifname> - interface name
<address> - IP address
<mask> - subnet mask
