Vlan configuration – Rockwell Automation 1783-EMS08T Stratix 6000 Ethernet Managed Switch User Manual User Manual
Page 57
Rockwell Automation Publication 1783-UM001D-EN-P - January 2013
57
Switch Management
Chapter 4
VLAN Configuration
A VLAN is a logical segment of network users and resources grouped by
function, team, or application. This segmentation is without regard to the
physical location of the users and resources. For example, VLANs can be based on
the departments in your company or by sets of users who communicate mostly
with each other.
VLAN can be configured to span multiple switches, so devices on separate
switches can communicate as though they are on the same subnet. A port that is
configured as a trunk port provides traffic for all VLANs across the port. VLAN
trunking is defined in IEEE 802.1Q.
VLAN is implemented on the 1783-EMS08T switch in these ways:
• VLAN is disabled by default. If VLAN is disabled, the following is true:
– Packets are filtered faster by the switch control processor.
– There is no need to internally configure VLAN after powerup.
– There is no need to reconfigure VLAN after a configuration change.
– You cannot set up a querier on a custom VLAN.
– No VLAN infomation is provided in the IGMP report.
• Each of the switch’s nine ports can be assigned the role of an access port
(end station) or a trunk port (switch/router).
• One VLAN can be specified as the management VLAN to provide
administrative access to the switch.
• The management VLAN is the only VLAN that can run IP services. IP
services include the following:
– Address Conflict Detection (ACD)
– BOOTP
– DHCP server
– SNMP
– CIP interface
• IGMP is supported on all VLANs. However, the IGMP querier function
is limited to only one VLAN. The querier function is assigned to the
management VLAN by default, but you can assign the querier to a custom
VLAN instead of the management VLAN, as described on
.
• The number of VLANs you can have is determined by the number of
devices, as defined by this formula:
devices per VLAN = 4000/number of VLANs
For instance, if you have 4,000 devices, you can have 500 VLANs with
eight devices on each VLAN (4000/500 = 8).
IMPORTANT
The virtual local-area network (VLAN) feature used in earlier firmware
revisions has been renamed port segmenting. As of firmware revisions 0.11
and 0.53, a new VLAN feature is provided for only the 1783-EMS08T switch. For
more information about port segmenting, refer to