DHCP exclusions

PhilippeB
PhilippeB Posts: 18  Freshman Member
First Comment Friend Collector

Is there a simple way to configure DHCP exclusions? We want to use a DHCP range from 192.168.124.0 ~ 192.168.127.253 with the following exceptions:
- 192.168.124.0 ~ 192.168.124.99
- 192.168.125.0 ~ 192.168.125.99
- 192.168.126.0 ~ 192.168.126.99
- 192.168.127.0 ~ 192.168.127.99

The goal is that every IP address given by the DHCP server has three digits on the last octet. Therefore, any address given by the DHCP server should be in one of these ranges:
192.168.124.100 ~ 192.168.124.255
192.168.125.100 ~ 192.168.125.255
192.168.126.100 ~ 192.168.126.255
192.168.127.100 ~ 192.168.127.253

This is the IP settings that we use:

Best regards, Philippe

All Replies

  • PeterUK
    PeterUK Posts: 3,389  Guru Member
    100 Answers 2500 Comments Friend Collector Seventh Anniversary

    No way to do this you would need to use a 3rd party DHCP server

    or you can setup VLAN's to a switch

  • PhilippeB
    PhilippeB Posts: 18  Freshman Member
    First Comment Friend Collector

    @PeterUK , thanks for your confirmation. We thought that there isn't a simple way.

    We probably solve it with a workaround and we'll define placeholders in the static DHCP table like this:

  • StefanZ
    StefanZ Posts: 202  Master Member
    First Comment First Answer Friend Collector Community MVP
    edited March 3

    Why don't you just start your DHCP pools at .100?

    You can still use static IPs with other clients like permanent infrastructure.

    I do this – the Router is .1, the switches are .2 – .10, WiFi-APs .11 – .20, etc., PC clients start at .100.

    Also: How is a IPv4 /24 Pool Size of 1023 possible? :-D

  • PhilippeB
    PhilippeB Posts: 18  Freshman Member
    First Comment Friend Collector

    The answer to the last question probably solves the mystery. As you can see in the screenshot, it's a /21 network. That's why the GUI allows a pool size of 1023 addresses. My customer doesn't nee more than 500 DHCP addresses, but would like to have all of them with three digits on the fourth octet (just for cosmetic reasons only),

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