iES22GF User’s Manual
54
iS5 Communications Inc.
Relay
Label
Description
Relay Mode
Indicates the existing DHCP relay mode. The modes include:
Enabled
: activate DHCP relay. When DHCP relay is enabled, the agent
forward and transfers DHCP messages between clients and the server
when they are not in the same subnet domain, in order to prevent the
DHCP broadcast message from flooding for security considerations.
Disabled
: Disable DHCP relay
Relay Server
Indicates the DHCP relay server IP address. A DHCP relay agent is used to
forward and transfer DHCP messages between the client and the server
when they are not in the same subnet domain.
Relay Information Mode
Indicates the existing DHCP relay information mode. The format of DHCP
option 82 circuit ID format is "[vlan_id][module_id][port_no]". The first
four characters represent the VLAN ID, the fifth and sixth characters are
the module ID. In stand-alone devices, the module ID always equals to 0;
in stacked devices, it means switch ID. The last two characters are the
port number. For example, "00030108" means the DHCP message
received form VLAN ID 3, switch ID 1, and port No. 8. The option 82
remote ID value equals to the switch MAC address.
The mode include:
Enabled
: activate DHCP relay information. When DHCP relay information
is enabled, the agent inserts specific information (option 82) into a DHCP
message when forwarding to a DHCP server, and removes it from a
DHCP message when transferring to a DHCP client. It only works when
the DHCP relay mode is enabled.
Disabled
: disable DHCP relay information
Relay Information Policy
Indicates the policies to be enforced when receiving DHCP relay
information. When DHCP relay information mode is enabled, if the agent
receives a DHCP message that already contains relay agent information,
it will enforce the policy. The Replace option is invalid when relay
information mode is disabled. The policy includes:
