(Optional) Configuring DHCP Data Restoration

Context

Automatically saving IP address allocation information allows the DHCP server to re-allocate the same configurations (such as IP address and lease time) to clients in the event that the server unexpectedly restarts.

After this function is enabled, the DHCP server stores lease information in lease.txt and conflicting IP addresses in conflict.txt (both data files are saved to the DHCP folder). New data files overwrite earlier data files.

The time displayed in the lease.txt and conflict.txt files is the UTC time rather than the system time, and you do not need to pay attention to time zone information.
To view information about the DHCP database, run the display dhcp server database command.
During the interval, if the device restarts unexpectedly, DHCP data generated at the interval are lost. Users can only recover the last successfully saved DHCP data from storage device files.

Procedure

Enter the system view.
```
system-view
```
Enable the DHCP server to automatically save IP address allocation information.
```
dhcp server database enable
```
By default, the DHCP server does not automatically save IP address allocation information.
Specify the interval at which the DHCP server saves IP address allocation information.
```
dhcp server database write-delay interval
```
By default, IP address allocation information is saved every 7200 seconds in data files. The new data files overwrite the earlier data files.
Enable the DHCP server to recover IP address allocation information from the data files upon a restart.
```
dhcp server database recover
```
By default, the DHCP server is disabled from recovering IP address allocation information from the data files upon a restart.