This article is from a FAQ concerning SCO operating systems. While some of the information may be applicable to any OS, or any Unix or Linux OS, it may be specific to SCO Xenix, Open There is lots of Linux, Mac OS X and general Unix info elsewhere on this site: Search this site is the best way to find anything.
This is an ancient post with no relevance to modern systems.
This error can be caused for various reasons. First, determine the cause of the problem and implement a solution. Then install all required SLSes according to the following paragraph, derived from TA 440249.
For SCO UNIX System V/386 Release 3.2 Operating System (the original version) SLS unx223 must be installed prior to installation of SLS unx257. For SCO Open Desktop Release 1.0.0 and 1.0.1, UFE should be installed prior to unx257. For 3.2.2 without Maintenance Supplement 1 and for ODT 1.1 without update G, install unx257 on its own (MS1 and UG both include unx257, and if you have them, you should not install unx257). SCO Unix 3.2v4 and ODT 2.0 have more up-to-date security, and unx257 should not be installed on either. Note that few, if any, of these supplements are available any longer.
The following is from TA 480020.
CAUSE 1: The file /etc/auth/system/ttys has become corrupted. Reboot the system and enter single user (System Maintenance) mode. Edit the file and insert the following line if it does not exist:
This file should only contain entries for your terminals (ttyxx - where xx is the tty number). Each entry ends with :chkent:. Remove unwanted lines.
CAUSE 2: After installation of a multiport intelligent serial board the file /etc/auth/system/ttys did not get updated with new entries for each tty port. These entries can be created by taking the following steps:
CAUSE 3: This message can be generated sporadically on a system with a large number of users logging on and off. Check the /etc/auth/system directory for ttys files. If there are multiple files, the extra files must be removed.
When database files such as /etc/auth/system/ttys are updated, a renaming procedure is used to ensure that multiple accesses to the file are managed properly. The contents of the old file (ttys) are copied/updated to create the new -t file (ttys-t). After that is done the old file is moved to a -o file (ttys-o), the new file (ttys-t) is moved to the original name (ttys), and the ttys-o file is deleted.
It is important to verify which of the files is the more complete file. This file is usually the largest, but use vi, cat, or more commands to examine the content of the files for correctness and/or corruption. Once you have determined which file is the most correct, make sure it is renamed to ttys, and remove all others.
It is recommended that you have "OVERRIDE=tty01" in the file /etc/default/login. That way root can always log in on that terminal when in multiuser mode.
NOTE 1: if this error message appears on just one port and no other ports are affected or prevented from logging in, then ckeck to make sure the device has just one link. If the device has more than one link, remove it and recreate it with mknod.
NOTE 2: TCP/IP 1.1.1 has an old /bin/login which can cause this problem. This release of TCP/IP is unsupported.
Got something to add? Send me email.