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Remote ID
(Option 37)
Identifies the host from which the message is received.
The default values of the Options 18 and 37 are as follows:
● Default Agent Interface ID is constructed in the format VLANID:LagID:SlotID:PortStr. When the port is fanned-out,
the PortStr is represented as mainPort:subPort (all in ASCII format).
● Default Agent Remote ID is the system MAC address of the relay agent that adds Option 37 (in binary format).
Releasing and Renewing DHCP-based IP Addresses
On an Aggregator configured as a DHCP client, you can release a dynamically-assigned IP address without removing the DHCP
client operation on the interface.
To manually acquire a new IP address from the DHCP server, use the following command.
● Release a dynamically-acquired IP address while retaining the DHCP client configuration on the interface.
EXEC Privilege mode
release dhcp interface type slot/port
● Acquire a new IP address with renewed lease time from a DHCP server.
EXEC Privilege mode
renew dhcp interface type slot/port
Viewing DHCP Statistics and Lease Information
To display DHCP client information, enter the following show commands:
● Display statistics about DHCP client interfaces.
EXEC Privilege
show ip dhcp client statistics interface type slot/port
● Clear DHCP client statistics on a specified or on all interfaces.
EXEC Privilege
clear ip dhcp client statistics {all | interface type slot/port}
● Display lease information about the dynamic IP address currently assigned to a DHCP client interface.
EXEC Privilege
show ip dhcp lease [interface type slot/port]
View the statistics about DHCP client interfaces with the show ip dhcp client statistics command and the lease information
about the dynamic IP address currently assigned to a DHCP client interface with the show ip dhcp lease command.
Example of the show ip dhcp client statistics Command
Dell#show ip dhcp client statistics interface managementethernet 0/0
Interface Name Ma 0/0
Message Received
DHCPOFFER 0
DHCPACK 0
DHCPNAK 0
Message Sent
DHCPDISCOVER 1626
DHCPREQUEST 0
DHCPDECLINE 0
DHCPRELEASE 0
DHCPREBIND 0
DHCPRENEW 0
DHCPINFORM 0
Dell#
Example of the show ip dhcp lease Command
Dell# show ip dhcp
Interface Lease-IP Def-Router ServerId State Lease Obtnd At Lease Expires At
Dynamic Host Configuration Protocol (DHCP)
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