Ip Multinetting; Ip Interface Setup - D-Link xStack DGS-3324SRi User Manual

xStack DGS/DXS-3300 Series Layer 3 Stackable Gigabit Ethernet Switch User Manual

IP Multinetting

IP Multinetting is a function that allows multiple IP interfaces to be assigned to the same VLAN. This is beneficial to the
administrator when the number of IPs on the original interface is insufficient and the network administrator wishes not to
resize the interface. IP Multinetting is capable of assigning another IP interface on the same VLAN without affecting the
original stations or settings of the original interface.
Two types of interfaces are configured for IP multinetting, primary and secondary, and every IP interface must be
classified as one of these. A primary interface refers to the first interface created on a VLAN, with no exceptions. All other
interfaces created will be regarded as secondary only, and can only be created once a primary interface has been
configured. There may be five interfaces per VLAN (one primary, and up to four secondary) and they are, in most cases,
independent of each other. Primary interfaces cannot be deleted if the VLAN contains a secondary interface. Once the user
creates multiple interfaces for a specified VLAN (primary and secondary), that set IP interface cannot be changed to
another VLAN.
IP Multinetting is a valuable tool for network administrators requiring a multitude of IP addresses, but configuring the
Switch for IP multinetting may cause troubleshooting and bandwidth problems, and should not be used as a long term
solution. Problems may include:
The Switch may use extra resources to process packets for multiple IP interfaces.
•
The amount of broadcast data, such as RIP update packets and PIM hello packets, will be increased.
•

IP Interface Setup

Each VLAN must be configured prior to setting up the VLAN's corresponding IP interface.
An example is presented below:
In this case, six IP interfaces are required, so a CIDR notation of 10.32.0.0/11 (or a 11-bit) addressing scheme will work.
This addressing scheme will give a subnet mask of 11111111.11100000.00000000.00000000 (binary) or 255.224.0.0
(decimal).
Application Limitation: A multicast router cannot be connected to IP
interfaces that are utilizing the IP Multinetting function.
NOTE: Only the primary IP interface will support the BOOTP relay agent.
VLAN Name
System (default)
Engineer
Marketing
Finance
Sales
Backbone
Table 6- 4. VLAN Example - Assigned Ports
VID Switch Ports
1 5, 6, 7, 8, 21, 22, 23, 24
2 9, 10, 11, 12
3 13, 14, 15, 16
4 17, 18, 19, 20
5 1, 2, 3, 4
6 25, 26
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