Hello everyone,
Today I will share with you how to clear DHCP address pool binding and maintain a DHCP Address Pool.
Clear DHCP address pool binding
On the device acting as a DHCP server, unbind the fixed IP address assigned to a client. For example, in an address pool with a network segment address of 10.1.1.0 and a mask length of 24, the IP address 10.1.1.5 has been fixedly assigned to a certain client. If you want to unbind, you can take the following measures:
Configuration in the global address pool:
Withdraw the IP address 10.1.1.5.
<HUAWEI> reset ip pool name pool1 10.1.1.5
Cancel the static binding relationship.
<HUAWEI> system-view
[HUAWEI] ip pool pool1
[HUAWEI-ip-pool-pool1] undo static-bind ip-address 10.1.1.5
Configuration in the interface address pool:
Withdraw the IP address 10.1.1.5.
<HUAWEI> reset ip pool interface vlanif100 10.1.1.5
Cancel the static binding relationship.
<HUAWEI> system-view
[HUAWEI] interface vlanif 100
[HUAWEI-Vlanif100] undo dhcp server static-bind ip-address 10.1.1.5
Resetting a DHCP Address Pool
When the device functions as a DHCP server, you can reset the DHCP address pool to re-allocate IP addresses to clients or set the IP addresses in the address pool to idle (the idle IP addresses are preferentially allocated).
Run the following command to reset the configured DHCP address pool:
For the interface address pool:
Run the reset ip pool interface interface-name {start-ip-address [end-ip-address] | all | conflict | expired | used} command.
For a global address pool:
Run the reset ip pool name ip-pool-name {start-ip-address [end-ip-address] | all | conflict | expired | used} command.
When the device functions as a DHCP relay agent, run the following command to request the DHCP server to release the IP address of the client:
After a DHCP relay agent is configured to request a DHCP server to release the IP address of a client, the DHCP relay agent sends a DHCP RELEASE message to the specified DHCP server. After receiving the message, the DHCP server resets the specified IP address to the idle state. In this way, the released IP address can be allocated to other DHCP clients.
system-view
interface interface-type interface-number[.subinterface-number ]
dhcp relay release client-ip-address mac-address [ vpn-instance vpn-instance-name ] [ server-ip-address ]
In the system view, when the DHCP relay agent is configured to release IP addresses of clients:
If the DHCP server is not specified, the DHCP server sends a release request to the DHCP server corresponding to all interfaces configured in relay mode.
If the IP address of the DHCP server is specified, the DHCP server sends a release request to the specified DHCP server.
When you configure the DHCP relay agent to release the IP address of a client in the interface view:
If no DHCP server is specified, the DHCP server sends a release request to the DHCP server corresponding to the interface.
If the IP address of the DHCP server is specified, the DHCP server sends a release request to the specified DHCP server.
Forcing a DHCP Client to Release and Renew Its IP Address
If a DHCP client obtains its IP address dynamically, you can force the client to release and renew its IP address, which is useful during certain troubleshooting procedures.
The commands used to release and renew an IP address depend on the operating system running on the client. For details about the commands to run, see the documentation of your operating system. The commands for some common operating systems are as follows:
Release an IP address.
For Windows 7, run the ipconfig/release command.
For MS-DOS of Windows 98, run the winipcfg/release command.
For Unix-like operating systems, run the dhclient –r command.
Renew an IP address lease or apply for a new IP address.
For Windows 7, run the ipconfig/renew command.
For MS-DOS of Windows 98, run the winipcfg/renew command.
For Unix-like operating systems, run the dhclient command.
That is all I want to share with you! Thank you!
