New to Pfsense - DHCP Exclusion



  • I just need to know how to exclude an IP from being distribute by DHCP?

    Thanks in advance



  • Do you mean you want a specific address for a device?  If so, you can do that on the DHCP server tab, at the bottom, in "DHCP Static Mappings for this Interface".  I don't know if it's required with pfSense, but it's generally a good idea to keep those addresses outside of the DHCP address pool.



  • first off tanks for your prompt response,
    I want to exclude an IP from being giving by DHCP.

    My DHCP range is form (192.168.0.11) to (99) and I don't want DHCP to give out some IPs within that rang such as (192.168.0.80)



  • It might help to know what you're trying to do with this.  If you have some reason to not allow that specific address to be handed out, then do what I described in the other post, but use a dummy MAC address.  That address will then never be handed out.  But somehow, I think there's more to this than what you're saying. If so, there may be a better way to do what you want.



  • Somplu I want to exclude these ip because it's already occupied by some printers and other devices.

    I used to do it in one step with Microsoft DHCP that's why I can't find it easy :)



  • I assume those devices have a static address?  If so, just give them addresses outside of the DHCP address pool.  For example, you might have the pool configured for 192.168.0.100 to 192.168.0.199.  You then can give static addresses outside that range to those devices.  Or you could configure them to use DHCP and create a static mapping between the MAC address and IP address.  Either way will work fine.


  • Rebel Alliance Global Moderator

    The devices with static IPs on your network should be outside your pool.  If you have devices inside your pool, even if the client is already set inside the pool.  And you want to be clean about it create multiple pools skipping those IPs.  But would prob just be easier to change those devices so they are not in the pool range.

    You can have multiple pools.  So for example with your .80 just create pools

    192.168.0.11-79

    Then create next pool

    192.168.0.81-99

    You can have many pools setup skipping over single IPs or ranges of IPs if your setting those clients as static.. But its much simpler and cleaner to just put your devices outside the pool.. If your pool is .11-99 then your statics could be .1 to .10 and .100 to .254 if your using a /24



  • In fact I can't change some devices IP. But now I got a question, when I enabled the DHCP server I defined the range of IPs but didn't make Pools, though my DHCP still handing out IPs! So you mean if I make pool range my DHCP will pass IP from pool ranges only and not from the whole range?



  • @Hamooda:

    In fact I can't change some devices IP. But now I got a question, when I enabled the DHCP server I defined the range of IPs but didn't make Pools, though my DHCP still handing out IPs! So you mean if I make pool range my DHCP will pass IP from pool ranges only and not from the whole range?

    All you have to specify is the available range.  You'd only use the additional pools if you needed more pools.  As for those devices you can't change, you can always create a DHCP entry for their address and use the device's MAC address.  That way, no other device can get that address.



  • Thanks a lot, I will try thatbnext Sunday and will let you know. Much appreciated your advice.


  • Rebel Alliance Global Moderator

    "you can always create a DHCP entry for their address and use the device's MAC address."

    No not really, you can not create a reservation for IP inside the pool.. If you mean create a dummy lease? How exactly you going to do that?

    Why not just do the pools.. Clickity Clickity done!




  • "you can always create a DHCP entry for their address and use the device's MAC address."

    No not really, you can not create a reservation for IP inside the pool.

    Sorry, forgot about that.

    Still, I don't think I've ever seen an IP device that couldn't be configured for a specific address, if not DHCP.  However, I have seen some that were difficult to configure in that I had to manually create an arp entry and then use that IP to access the device.



  • Thanks to all, I solve it by IP reservation and used fake MAC address.


  • Rebel Alliance Global Moderator

    How exactly did you do that, pfsense does not allow you to create reservations for IPs "inside" the pool range..