Hi, @emad said in Nginx "404 Not Found" Error after POST action to "$PORTAL_ACTION%2quot;: So, do I miss knowledge with CP behavior or should I modify something? You might as well check (== read and understand what happens when and why etc) this file /usr/local/captiveportal/index.php It's the file that's get 'executed' when a users is redirected that the portal login interface. Read that file carefully - and also check this one : /etc/inc/captiveportal.inc which contains all the functions. For instance, you'll find why/where/when a string like $PORTAL_ACTION$ is replaced by the correct URL before getting send to the client. Throwing $PORTAL_ACTION$ at the client's web browser who throws it back to the captive portal web server will produce 404 errors.

@stephenw10 I just tried it again and it works. Looks like they finally updated their certs. Thanks for the help!

If you want hostA.domain.tld to return local hostB.domain.tld to return public hostC.domain.tld to return local Then you would have to create host overrides for each specific fqdn that you want to return local. Or you can go the other way and do a redirect, and then just create records that point to your public IP for those fqdn.. Depends on how many you have on what side, etc.