R0106-HP MSR Router Series Layer 3 - IP Services Command Reference(V7)

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undo dhcp relay client-information refresh enable
Default
The DHCP relay agent periodically refreshes relay entries.
Views
System view
Predefined user roles
network-admin
Usage guidelines
A DHCP client unicasts a DHCP-RELEASE message to the DHCP server to release its IP address. The
DHCP relay agent conveys the message to the DHCP server and does not remove the IP-to-MAC entry of
the client.
With this feature, the DHCP relay agent uses the IP address of a client and the MAC address of the DHCP
relay interface to periodically send a DHCP-REQUEST message to the DHCP server.
• If the server returns a DHCP-ACK message or does not return any message within an interval, the
DHCP relay agent performs the following operations:
{ Removes the relay entry.
{ Sends a DHCP-RELEASE message to the DHCP server to release the IP address.
• If the server returns a DHCP-NAK message, the relay agent keeps the entry.
With this feature disabled, the DHCP relay agent does not remove relay entries automatically. After a
DHCP client releases its IP address, you must use the reset dhcp relay client-information on the relay
agent to remove the corresponding relay entry.
Examples
# Disable periodic refresh of relay entries.
<Sysname> system-view
[Sysname] undo dhcp relay client-information refresh enable
Related commands
• dhcp relay client-information record
• dhcp relay client-information refresh
• reset dhcp relay client-information
dhcp relay information circuit-id
Use dhcp relay information circuit-id to configure the padding content and padding format for the Circuit
ID sub-option of Option 82.
Use undo dhcp relay information circuit-id to restore the default.
Syntax
dhcp relay information circuit-id { string circuit-id | { normal | verbose [ node-identifier { mac | sysname
| user-defined node-identifier } ] } [ format { ascii | hex } ] }
undo dhcp relay information circuit-id
Default
The content mode is normal and the padding format is hex.