DHCP Reservations not being excluded from address pool

Article #:

Product

Castle

1713

Unified Threat Management

All

Summary

How to stop reserved DHCP addresses being assigned to devices.

Problem

With Smoothwall acting as the DHCP server, within the DHCP address pool, you also have static assignments for certain devices on your network. These static DHCP addresses should only been assigned the one network device, but you find it is being allocated as a "standard" DHCP address.

Solution

It is recommended, and best practice, to have address pools that do not overlap, particularly when using a combination of static and DHCP assignments.

If static IP addresses within the pool are currently (mis)assigned, do the following:

1. From the Smoothwall administration user interface, go to Services > DHCP > DHCP server.
2. Reduce the dynamic IP address pool range so that you free up enough IP addresses for all static-assigned IP addresses. For example, for 3 IP addresses change the pool from 192.168.2.2-192.168.2.253 to 192.168.168.2.2-192.168.2.200.
3. Adjust all static assignments to those newly freed up IP addresses.
4. When you click Save, you are prompted to restart the DHCP service. Click Restart to continue.
5. Reboot all devices that are currently using the DHCP service, or waiting for a lease to expire to resolve any IP address conflicts.

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30 August 2016

 

DMT

 

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