'who' output is blank, returns nothing

This document (7005415) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 9
SUSE Linux Enterprise Server 10
SUSE Linux Enterprise Server 11

Situation

Typing in 'who' at the command prompt returns to a blank prompt.
Typing in 'who --all' returns more info, but does not list users currently logged in.
ssh logins take up to 30 seconds to complete.

Resolution

/usr/bin/who uses the /var/run/utmp file to store information.  That file needs to have these attributes:
 
#ll /var/run/utmp
-rw-rw-r--  root  tty  ....  /var/run/utmp
 
In this case, it was observed that the 'rw' attributes were not there for both the user (root) and group (tty), just 'r'. 
 
To fix:
1.  chmod 664 /var/run/utmp
 
If that doesn't fix it:
1.  mv /var/run/utmp /var/run/utmp.old (rename the file)
2.  touch /var/run/utmp (create a new file)
3.  chown root:tty /var/run/utmp (set the user and group correctly)
4.  chmod 664 /var/run/utmp (set the file attributes correctly)
 
Now users logging in to the console or ssh should be able to use the 'who' command and have the names show up in the list.

Disclaimer

This Support Knowledgebase provides a valuable tool for SUSE customers and parties interested in our products and solutions to acquire information, ideas and learn from one another. Materials are provided for informational, personal or non-commercial use within your organization and are presented "AS IS" WITHOUT WARRANTY OF ANY KIND.

  • Document ID:7005415
  • Creation Date: 01-Mar-2010
  • Modified Date:03-Mar-2020
    • SUSE Linux Enterprise Server

< Back to Support Search

For questions or concerns with the SUSE Knowledgebase please contact: tidfeedback@suse.com

SUSE Support Forums

Get your questions answered by experienced Sys Ops or interact with other SUSE community experts.

Join Our Community

Support Resources

Learn how to get the most from the technical support you receive with your SUSE Subscription, Premium Support, Academic Program, or Partner Program.


SUSE Customer Support Quick Reference Guide SUSE Technical Support Handbook Update Advisories
Support FAQ

Open an Incident

Open an incident with SUSE Technical Support, manage your subscriptions, download patches, or manage user access.

Go to Customer Center