Alcatel-Lucent OmniSwitch 6250, Cli Reference Manual, Page: 774 / 2018

Port Mobility Commands
page 21-6 OmniSwitch 6250 CLI Reference Guide November 2009
vlan dhcp port
Defines a DHCP port rule for an existing VLAN. If a DHCP frame is received on a mobile port that
matches the port specified in the rule, the mobile port is temporarily assigned to the rule’s VLAN.
vlan vid dhcp port slot/port
vlan vid no dhcp port slot/port
Syntax Definitions
vid VLAN ID number (1–4094).
slot/port The slot number for the module and the physical mobile port number on
that module (e.g., 3/1 specifies port 1 on slot 3). To enter multiple slots
and ports in a single command, use a hyphen to specify a range of ports
(e.g., 3/1-16) and a space to specify multiple slots (e.g., 3/1-16 5/10-20
8/2-9).
Defaults
N/A
Platforms Supported
OmniSwitch 6250
Usage Guidelines
•
Use the no form of this command to delete a DHCP port rule from the specified VLAN.
•
Port mobility software checks for and processes DHCP traffic first on an active mobile port. When a
mobile port receives a DHCP frame that matches a DHCP rule, the port is temporarily assigned to the
VLAN long enough to forward the DHCP requests within the VLAN broadcast domain. The source
MAC address of the DHCP frame, however, is not learned for that VLAN port association.
•
Once a DHCP device has obtained an IP address, its non-DHCP traffic must match other VLAN rules
within the same VLAN for the device to remain a member of that VLAN. If this match occurs, then the
frame source is learned in the matching rule VLAN.
•
DHCP rules are most often used in combination with IP network address rules. A DHCP client has an
IP address of all zeros (0.0.0.0) until it receives an IP address from a DHCP server, so it would not
match any IP network address rules.
•
Binding rules, MAC address rules, and protocol rules also capture DHCP client traffic. The exception
to this is binding rules that specify an IP address as part of the rule, similar to IP network address rule
definitions.
•
Rules are only assigned to existing VLANs. Use the vlan command to create a new VLAN.