Allied Telesis AT-8550 - Manual (Page 136)

IP Multinetting
8-8
IP Multinetting
IP multinetting is used in many legacy IP networks when there is a
need to overlap multiple subnets into one physical segment. On the
switch, you can only assign a single IP address to a router interface
(one IP address per VLAN). To support IP multinetting, you must
assign multiple VLANs to the same physical port. The switch routes IP
traffic from one subnet to another, all within the same physical port.
The following rules apply when you are configuring IP multinetting:
❑ A maximum of one IP address is associated with a router
interface (or VLAN).
❑ Multiple VLANs must be used to implement IP multinetting.
❑ A maximum of four subnets are allowed on one multinetted
port.
❑ For multinetted segments that span multiple ports, you must
configure all the multinetted VLANs with the same port
assignment.
❑ A maximum of one VLAN can run RIP or OSPF, and this VLAN
must be configured to use the IP protocol.
Note
BootP works only on the VLAN assigned to the IP protocol.
❑ The FDB aging timer is automatically set to 3,000 (5 minutes).
❑ If you are using BootP/DHCP relay, only the VLAN that
contains the IP protocol filter is able to service BootP and
DHCP requests.