Correlating A Dhcp Server Group With Relay Agent Interfaces - 3Com MSR 50 Series Configuration Manual

592 C 34: DHCP R
HAPTER
n
Correlating a DHCP
Server Group with Relay
Agent Interfaces
n
A C
ELAY GENT ONFIGURATION
To do...
Enter system view
Enter interface view
Enable the DHCP relay agent
on the current interface
If you enabled the DHCP relay agent on an Ethernet subinterface, a client
■
connected must also use a subinterface to guarantee normal communication
with the relay agent. In this case, if the client is a PC, it cannot obtain an IP
address.
If the DHCP client obtains an IP address via the DHCP relay agent, the address
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pool of the subnet which the IP address of the DHCP relay agent belongs to
must be configured on the DHCP server. Otherwise, the DHCP client cannot
obtain a correct IP address.
To improve reliability, you can specify several DHCP servers as a group on the
DHCP relay agent and correlate a relay agent interface with the server group.
When the interface receives requesting messages from clients, the relay agent will
forward them to all the DHCP servers of the group.
To correlate a DHCP server group with relay agent interfaces, use the following
commands:
To do...
Enter system view
Specify a DHCP server group
number and servers in the
group
Enter interface view
Correlate the DHCP server
group with the current
interface
You can specify at most twenty DHCP server groups on the relay agent and at
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most eight DHCP server addresses for each DHCP server group.
The IP addresses of DHCP servers and those of relay agent's interfaces cannot
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be on the same subnet. Otherwise, the client cannot obtain an IP address.
A DHCP server group can correlate with one or multiple DHCP relay agent
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interfaces, while a relay agent interface can only correlate with one DHCP
server group. Using the dhcp relay server-select command repeatedly
overwrites the previous configuration. However, if the specified DHCP server
group does not exist, the interface still uses the previous correlation.
The group-id in the dhcp relay server-select command was specified by the
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dhcp relay server-group command.
Use the command...
system-view
Interface interface-type
interface-number
dhcp select relay
Use the command...
system-view
dhcp relay server-group
group-id ip ip-address
interface interface-type
interface-number
dhcp relay server-select
group-id
Remarks
-
-
Required
With DHCP enabled,
interfaces work in the DHCP
server mode.
Remarks
-
Required
Not specified by default
-
Required
By default, no interface is
correlated with any DHCP
server group.