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MES-2110 User’s Guide
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DHCP Relay Configuration
18.1 Overview
Configure DHCP relay on the MES-2110 if the DHCP clients and the DHCP server
are not in the same broadcast domain. During the initial IP address leasing, the
MES-2110 helps to relay network information (such as the IP address and subnet
mask) between a DHCP client and a DHCP server. Once the DHCP client obtains an
IP address and can connect to the network, network information renewal is done
between the DHCP client and the DHCP server without the help of the MES-2110.
The MES-2110 can be configured as a global DHCP relay. This means that the
MES-2110 forwards all DHCP requests from all domains to the same DHCP server.
You can also configure the MES-2110 to relay DHCP information based on the
VLAN membership of the DHCP clients.
18.1.1 DHCP Relay Agent Information
The MES-2110 can add information about the source of client DHCP requests that
it relays to a DHCP server by adding Relay Agent information. This helps provide
authentication about the source of the requests. The DHCP server can then
provide an IP address based on this information. Please refer to RFC 3046 for
more details.
The DHCP Relay Agent feature adds an additional parameter to the Option 82
field. The Option 82 field is in the DHCP headers of client DHCP request frames
that the MES-2110 relays to a DHCP server.
The following describes the DHCP relay information that the MES-2110 sends to
the DHCP server:
Table 51
Relay Agent Information
FIELD LABELS
DESCRIPTION
Slot ID
(1 byte) This value is always 0 for stand-alone non-card based
switches.
Port ID
(1 byte) This is the port that the DHCP client is connected to.
Summary of Contents for ES-100
Page 2: ......
Page 8: ...Safety Warnings MES 2110 User s Guide 8 ...
Page 10: ...Contents Overview MES 2110 User s Guide 10 ...
Page 17: ...Table of Contents MES 2110 User s Guide 17 Index 229 ...
Page 18: ...Table of Contents MES 2110 User s Guide 18 ...
Page 50: ...Chapter 4 Tutorials MES 2110 User s Guide 50 ...
Page 74: ...Chapter 8 Loop Detection MES 2110 User s Guide 74 ...
Page 76: ...Chapter 9 Jumbo Frame MES 2110 User s Guide 76 ...
Page 88: ...Chapter 10 802 1x MES 2110 User s Guide 88 ...
Page 136: ...Chapter 17 IGMP MES 2110 User s Guide 136 ...
Page 140: ...Chapter 18 DHCP Relay Configuration MES 2110 User s Guide 140 ...
Page 150: ...Chapter 19 IP Source Guard MES 2110 User s Guide 150 ...
Page 206: ...Chapter 23 Command Line Interface MES 2110 User s Guide 206 ...
Page 214: ...Chapter 24 Troubleshooting MES 2110 User s Guide 214 ...
Page 220: ...Appendix A Changing a Fuse MES 2110 User s Guide 220 ...
Page 228: ...Appendix C Legal Information MES 2110 User s Guide 228 ...