Section 23.1.5, Example – Westermo RedFox Series User Manual
Page 525

Westermo OS Management Guide
Version 4.17.0-0
relayed by RA4 to the DHCP server, will be forwarded through RA5 like any
other packet.
23.1.5
Mitigating duplication of DHCP messages by using a dif-
ferent server port
An alternative to address the issue with multiple DHCP requests in switched
topologies with non-snooping relay agents is to let the DHCP server listen on a
non-standard UDP port (
). The DHCP relay agent can be configured
to forward its packets to this server port (
), thus all relayed packets
will reach the server. Packets coming directly from the client will be dropped by
server, since they are sent to the regular DHCP server UDP port (67).
Example
-- DHCP Server configuration of non-standard listen port
example-server:/#> configure
example-server:/config/#>
example-server:/config/#> dhcp-server
example-server:/config/dhcp-server/#> server-port 6767
example-server:/config/dhcp-server/#> leave
Stopping DHCP/DNS Server ................................... [ OK ]
Starting DHCP/DNS Server ................................... [ OK ]
Configuration activated.
Remember "copy run start" to save to flash (NVRAM).
example-server:/#>
-- DHCP Relay Agent configuration of non-standard server port
example-relay:/#> configure
example-relay:/config/#> dhcp-relay
example-relay:/config/dhcp-relay/#> server-port 6767
example-relay:/config/dhcp-relay/#> leave
Stopping DHCP/DNS Server ................................... [ OK ]
Starting DHCP/DNS Server ................................... [ OK ]
Configuration activated.
Remember "copy run start" to save to flash (NVRAM).
Starting DHCP Relay Agent .................................. [ OK ]
example-relay:/#>
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