Dhcp Commands - Alcatel-Lucent 7750 SR OS Service Manual

DHCP Commands

dhcp
Syntax dhcp
Context config>service>vprn>interface
config>service>vprn>subscriber-interface
config>service>vprn>sub-if>grp-if
Description
This command enables the context to configure DHCP parameters.
action
Syntax action {replace | drop | keep}
no action
Context config>service>vprn>if>dhcp>option
config>service>vprn>sub-if>grp-if>dhcp>option
Description
This command configures the processing required when the SR-Series receives a DHCP request that
already has a Relay Agent Information Option (Option 82) field in the packet.
The no form of this command returns the system to the default value.
Default
Per RFC 3046, DHCP Relay Agent Information Option , section 2.1.1, Reforwarded DHCP requests,
the default is to keep the existing information intact. The exception to this is if the giaddr of the
received packet is the same as the ingress address on the router. In that case the packet is dropped and
an error is logged.
Parameters
replace — In the upstream direction (from the user), the existing Option 82 field is replaced with the
drop — The packet is dropped, and an error is logged.
keep — The existing information is kept in the packet and the router does not add any additional
circuit-id
Syntax circuit-id [ascii-tuple | ifindex | sap-id | vlan-ascii-tuple]
no circuit-id
7750 SR OS Services Guide
Option 82 field from the router. In the downstream direction (towards the user) the Option 82
field is stripped (in accordance with RFC 3046).
information. In the downstream direction the Option 82 field is not stripped and is sent on
towards the client.
The behavior is slightly different in case of Vendor Specific Options (VSOs). When the keep
parameter is specified, the router will insert his own VSO into the Option 82 field. This will only
be done when the incoming message has already an Option 82 field.
If no Option 82 field is present, the router will not create the Option 82 field. In this in that case,
no VSO will be added to the message.
Virtual Private Routed Network Services
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