Confirmation or Reassurance of pfSense DHCP reallocation after a full table

  • Good day!

    I have used a commercial Captive Portal which had its share of problems and I am moving over to pfSense. One of the problems with the commercial solution was that it would not provide a lease to a new PC (guest) after its allocation table was full and most leases expired. Had a similar problem with some SpeedStream devices too.

    This is in a hotel where many people come and go. The DHCP table will fill quickly with expired leases.

    I am after some confirmation or some reassurance that the DHCP server in pfSense WILL reallocate an IP address which is expired yet still remaining in the table (as expired) from some other PC, to a new PC/MAC.

    I have STFed (Searched the Forums) and found an old post in 2007, and it inferred that pfSense "should" reallocate expired leases that were still in the table. But nothing concrete. The posters then seemed to have a problem with this same issue. I Just don't want to have to do much hands on resets or DHCP restarts or manually clear the table every week or so.

    Thanks in advance for any information.


  • Rebel Alliance Developer Netgate

    It should be easy to test in a VM. Setup a DHCP pool of only 5 IPs and try it out, see what happens.

    I haven't ever filled up one of my DHCP pools so I can't say for certain what happens, but I believe it should reallocate from expired leases also.

  • @Jimp,

    Thanks! That is exactly what I was going to do today! Not in a VM but in a real world test scenario.  If it is a properly written/coded server, it should wihtout fail reallocate IPs still in the list but I am "gun shy" since some pretty high end stuff I have had in place simply didn't do that.

    Go figure! I will post back my results down the road.

    Thanks again!


  • I can state with confidence that pfSense's DHCP server is as I had hoped. Seems fully compliant and once a lease has expired it will, in a top down fashion, reassign a long expired IP address to a new MAC.

    Again, this was just a concern because I did have some high end appliances, (or alledgedly high end),  that simply would stop providing IP addresses once the IP database was full as all IPs in the range had been allocated even though they were expired.

    Go figure!



Log in to reply