$ cat /etc/pam.d/login

HPAM-1.0

auth       required-    /lib/security/pam_securetty.so

auth       required     /lib/security/pam_stack.so service=system-auth

auth       required     /lib/security/pam_nologin.so

 login    ,    
     . .  11.5  11.6.

1.     pam_securetty ("secure tty"   -
),       root   -
  (  root    login  ;  -
     ).   -
 pam securetty      .
 pam_securetty     ,  - 
    root   .    (
    root     root,
      )  pam_securetty
   .

         , -
   .       -
     .

2.  pam stack, so     ,  
  ,       . 
service=system-auth    ,    system-auth 
 /etc/pam.d.   ,     -
    ,    
 .

3.   pam_nologin ,     /etc/nologin.txt
      root (   pam_nologin -
  ,      /etc/nologin.txt   -
   root).  ,   
  -      
   ,         .

  account    auth,    -
  .      -
        . , 
 account   ,       -
   .

  session     (,   -
   ).    
session   Red Hat Linux   pam_console,   -
    ,    ,  
.         -
-,       ,   -
.

442                                        IV.  