printk timing issues on boot

This document (000004686) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server 12SP4 for SAP

Situation

During bootup printk stack trace messages generated on console.Server times out for a period of time.

Resolution

pleas execute the following command
echo '3 4 1 7' > /proc/sys/kernel/printk

To make the change persistent, we would need to do
[1] Edit "/etc/sysctl.conf" and set "kernel.printk" to 
    kernel.printk = 3 4 1 7
2] Then run "sysctl -p" to make the change effective
 

Cause

Default settings for printk on SLES12 SP4 is:
# /proc/sys/kernel/printk
7    4    1    7

Status

Reported to Engineering

Additional Information

Customer saw on issue on RHEL image that had caused similar timing issues: The printk issue mentioned is related to https://bugzilla.kernel.org/show_bug.cgi?id=199003 The patch for this has been there for some time https://lkml.org/lkml/2016/4/22/487

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:000004686
  • Creation Date: 19-Mar-2020
  • Modified Date:19-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