Mac Whitelist on Captive Portal results in users not being able to connect 2.3.0

[amartin]

I am running pfSense 2.3.0 on a gatway with a captive portal configured on the OPT1 interface. I add most of the client MAC addresses to the captive portal's MAC whitelist so they can gain access without hitting the captive portal; this has been working well for years. Recently, some clients who have been on the whitelist for a long time suddenly can no longer get a lease from the pfSense DHCP server. Looking at the logs, I see the DHCPDISCOVER, then the DHCPOFFER, but never any DHCPREQUEST or DHCPACK. It just repeats the DHCPDISCOVER and then DHCPOFFER over and over. Restarting the captive portal or DHCP services on pfSense does not fix the problem. However, deleting the MAC address for the MAC whitelist and then re-adding it does fix the problem.

I reviewed the changelog for 2.3.0 - 2.3.1_5 and didn't see anything regarding this problem. Any ideas why this is occuring, or why deleting from the MAC whitelist and re-adding fixes it? Thanks!