PureStream PureLink VIP-NET-M28A Media Hub, User Manual

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VIP-NET-M28A Network Switch - USER MANUAL
VERSION 1.0
Relay Agent
DHCP relay is used to forward and transfer DHCP messages between the clients and the server when they
are not in the same subnet domain. You can configure the function in this page.
Label Description
Relay Mode Indicates the existing DHCP relay mode. The modes include:
Enabled : activate DHCP relay. When DHCP relay is enabled,
the agent forwards and transfers DHCP messages between the
clients and the server when they are not in the same subnet
domain 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 clients 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, and 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 modes 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 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