[...] > >> This is on racktables 0.17.0 > > > > Do you run a modified version of the code? > > No, this is plain 0.17.0. > > Any idea how to debug this? I'd suggest checking first, that both things (RackTables and single-signon) work on its own. Then its worth configuring it back together and installing a checkpoint in auth.php/authenticate() to see the value of $_SERVER ['REMOTE_USER']. After that it should become clear, why $auto_tags isn't initialised properly. I'd suppose, that authenticate() isn't called at all, but the only way to get that with original code is to set $script_mode option, which again is something odd for a web-frontend. Could you check everything once more? -- Denis Ovsienko