We have the following problem with hotspot users authenticating by MAC address, with user-manager enabled and working.
Sometimes and especially after an accidental router reboot or a sudden electric failure, some MAC clients do not get authenticated, the message in the log is simply radius timed out.
We have tried a variety of possible fixes including increasing the radius timeout value, without success. The unauthenticated users have to be manually removed from the host list then they get successfully authenticated.
I have seen someone report the same problem on this forum, please advise if a fix is possible. or maybe a work around.