DHCP stops working when ip address and subnet are changed



  • Hello
    I have done a pfsense fresh install.. everything works on the LAN port with the ip 192.168.1.1 and subnet 255.255.255.0.
    Once I change the ip address class to 10.0.0.1/8 everything works as well.
    But the DHCP stops working once I go to SERVICE-DHCP SERVER and change the range of the starting ip to 10.0.0.2 -  10.255.255.253.

    The DCHP stops working and no computer on the LAN port can't automatically obtained an ip address…
    I am doing something wrong here with setting up the cidr ?

    Chris
    ![Screenshot from 2015-12-04 05:06:04.png](/public/imported_attachments/1/Screenshot from 2015-12-04 05:06:04.png)
    ![Screenshot from 2015-12-04 05:06:04.png_thumb](/public/imported_attachments/1/Screenshot from 2015-12-04 05:06:04.png_thumb)
    ![Screenshot from 2015-12-04 05:13:06.png](/public/imported_attachments/1/Screenshot from 2015-12-04 05:13:06.png)
    ![Screenshot from 2015-12-04 05:13:06.png_thumb](/public/imported_attachments/1/Screenshot from 2015-12-04 05:13:06.png_thumb)



  • dhcpd allocates a certain amount of memory for each available lease. Having a pool that huge is completely unnecessary, and would require gobs of RAM for dhcpd alone. Make the pool a reasonable size and you'll be fine. Probably better off with a /24 or /20 if you have a big network, using an entire /8 on a single broadcast domain isn't a good practice.



  • True, it was a memory limitation…. I did not know that the ip allocation would use that much resources from my server...
    Thanks



  • only when you reserve leases for >16million devices



  • @akieni:

    True, it was a memory limitation…. I did not know that the ip allocation would use that much resources from my server...
    Thanks

    16mil IPs times ( 4 bytes per IP plus 12 bytes per MAC address) is 256MiB. That is not including any other overhead like padding, time stamps, etc.


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