lighttdm and autofs template rules

[Emmanuel]

For some unknown reason, lightdm do not accept login when autofs is configured that way :

nas.home.autofs : /home /etc/auto.master.d/nas.home.folders --ghost,--timeout=600
nas.home.folders : * -fstype=cifs,uid=&,gid=&,file_mode=0640,dir_mode=0750,credentials=/etc/credentials.d/cre.&,iocharset=utf8 ://192.168.0.100/home.&

but it works if mounted directory are manually specified :

nas.home.autofs : /home /etc/auto.master.d/nas.home.folders --ghost,--timeout=600
nas.home.folders : My_account -fstype=cifs,uid=My_account,gid=My_account,file_mode=0640,dir_mode=0750,credentials=/etc/credentials.d/cre.My_account,iocharset=utf8 ://192.168.0.100/home.My_account

I suppose this is due to the fact that in the 1st method, home directory where not created by autofs. It only create them when an attempt to access it is done.

Please help to define trace and logs to analyse the reason.