What is an sosreport and how to create one in Red Hat Enterprise Linux?

Solution Verified - Updated -

Environment

  • Red Hat Enterprise Linux (RHEL) 4.6+, 5, 6, 7, 8
  • Red Hat Enterprise MRG

Issue

Resolution

Table of Contents

What is an sosreport?

The sosreport command is a tool that collects configuration details, system information and diagnostic information from a Red Hat Enterprise Linux system. For instance: the running kernel version, loaded modules, and system and service configuration files. The command also runs external programs to collect further information, and stores this output in the resulting archive.

» Why am I being asked to provide an sosreport?

The output of sosreport is the common starting point for Red Hat support engineers when performing an initial analysis of a service request for a Red Hat Enterprise Linux system.

The utility provides a standardized way to collect diagnostic information that your Red Hat support engineer will reference throughout their investigation of issues reported in support cases.

The use of sosreport helps to ensure that you are not being continually asked for piecemeal data outputs.

How can I generate an sosreport?

Once the sos package has been installed, issue the following command to run sosreport:

# sosreport
Notice The sosreport command requires root permissions to gather data correctly. There is no current mechanism to allow non-root executions of sosreport.
Notice Starting in RHEL 8, the sosreport command is deprecated in favor of sos report. A message to this affect is output if sosreport is issued on a RHEL 8 system and "Redirecting to 'sos report'" is performed.

The command will normally complete within a few minutes on Red Hat Enterprise Linux 6. Older versions may take longer to complete. Depending on local configuration and the options specified in some cases the command may take longer to finish. If you are concerned about the run time of the sosreport command contact your Red Hat support representative for assistance.

Once completed, sosreport will generate a compressed file under /tmp (for RHEL6 and earlier) or under /var/tmp (for RHEL7 and later). The file should be provided to your support representative (normally as an attachment to an open support case).

» Running sosreport results in "no valid plugins were enabled" message

  • Typically the "no valid plugins" message is output then the sosreport command run without full root privileges. The sosreport command requires root permissions to gather data from the system correctly. Many of the files, commands, and tools that it runs to gather information required root access privilege. For example, if multipath is configured on the system then sosreport will gather information from multipath subsystem on the current configuration settings, which it cannot do as a normal user.

    $ multipathd -k"show config"
need to be root

  • Please try running again as root, and if you are still experiencing issues, open a support case so that we may investigate.*

» Running sosreport fills my available disk space

  • The size of the archive varies depending on system configuration and any optional sosreport features that are enabled. For example --all-logs will greatly increase the size of the archive as it removes size-limiting features for command output and log file collection.

  • If /tmp/ or /var/tmp is too small to hold an sosreport archive, use the --tmp-dir option to specify an alternate location with sufficient available space.

» How do I provide an sosreport to Red Hat?

  • To post sosreport, or any other file, to an existing support case you can use the redhat-support-tool command line option, the Red Hat Portal UI or several different methods using FTP.
  • If the collected sosreport file is too big to upload to the case, it may be uploaded to the Red Hat FTP dropbox.
    • If you use the ftp option, update your support case with the exact filename as this is the only way your support engineer will be able to retrieve it.

» I do not have a case number yet, do I need to provide one for sosreport to run?

  • The case number input prompt is optional, and if provided the case number will be part of the archive's file name. Omitting the case number will not have any negative effect on running the sosreport command.

  • Also, the command may be run in batch mode using the --batch option in order to avoid the need to enter user and account information interactively.

How can I control how the sosreport command runs?

The sosreport command has a plugin structure and allows the user to enable and disable plugins and specify plugin options via the command line. Available plugins and their options may be listed by running the following command:

# sosreport -l

» How can I disable or enable specific plugins?

Users may selectively enable or disable plugins using the -e/--enable-plugins and -n/--skip-plugins options respectively. These options take comma-delimited lists of plugin names or may be specified multiple times. For example, to disable the amd and kvm plugins, use the following:

# sosreport -n kvm,amd

» How do I use plugin options?

Individual plugins may provide additional options that may be specified via the -k option. These options are listed in the same output as the listing of available plugins (sosreport -l). The format this option takes is plugin_name.option_name=value. For example, to enable collection of container logs, use the following:

# sosreport -k podman.logs=on

Options will specify whether they are boolean toggles or expect a string or integer. For boolean toggles, users may use True, on, or yes and False, off, or no interchangeably.

» Why does sosreport sometimes skip collecting certain command output?

An sosreport execution might print to console a message like the following:

[plugin:networking] skipped command 'nft list ruleset': required kernel modules or services not present (kmods=[nf_tables] services=[]).

sosreport aims to not alter the system it runs on in any way. Some commands called by certain plugins may automatically trigger a change (load a kernel module in the example above) and are thus gated by default. If making these changes is acceptable for your environment, and you would like to have sosreport make them in order to collect the skipped commands, run sosreport like so:

# sosreport --allow-system-changes

» *Running sosreport on my system uses too much CPU time or memory»* (it is supported with sos version 3.6 or later)

By default sosreport will run up to 4 plugins in parallel in an effort to reduce total runtime. This may cause memory contention or high CPU usage on certain systems depending on which plugins are being run (and particularly if each of those plugins collects journal output). To reduce the number of simultaneous collections use the --threads option. For example, to run plugins one at a time, use the following:

# sosreport --threads=1

Installing sosreport

The sos package must be installed in order to run the sosreport command. You can check to see if the sos package is installed and whether there is any problems with the installation using the following command:

# rpm -qa | grep sos
sos-3.2-35.el7_2.3.noarch                  << sos package is installed
# rpm -V sos                               << run verification on installed package

» Red Hat Enterprise Linux 5 and later

If the system is registered with RHSM, use the yum command:

# yum install sos

If the system is not registered with RHSM, the sos package can be downloaded from the RHN website or found on the installation CDs or DVD. The rpm command may be used to install the package on any version of Red Hat Enterprise Linux:

# rpm -Uvh sos-<version>.noarch.rpm

» Red Hat Enterprise Linux 4 Update 6 and later 4.x kernels

If the system is registered with Red Hat Subscription Manager (RHSM), sos can be installed using the up2date command:

# up2date sos

What to do if sosreport hangs

First, verify that there is enough free space available in either /tmp (RHEL 6) or /var/tmp (RHEL7 and later), and if not, use the --tmp-dir option as detailed earlier.

If sosreport is hanging/stalling on a specific plugin (currently running plugins are displayed during execution), try running sosreport with the problem plugin(s) disabled using the -n/--skip-plugins option as detailed earlier.

Note that each plugin has a default timeout of 5 minutes (controllable by the timeout plugin option available to all plugins). Please allow enough time for this timeout threshold to be hit, and sosreport should automatically terminate that plugin's execution. In the event that this termination does not happen, use the option highlighted above.

If an sosreport can not be completed at all for one reason or another, please see How to gather data from a Red Hat Enterprise Linux system for troubleshooting if the sosreport process goes to hung state? for further guidance.

I cannot run sosreport at all and would like to collect a bare minimum of data to provide

Please see sosreport fails. What data should I provide in its place? for an alternative bare-minimum data collection script.

For issue-specific guidance in the case of sosreport failure, please see Additional and alternative steps for gathering an sosreport for a Red Hat Enterprise Linux support case

What commands does a particular sosreport plugin run in the background?

There are following ways to understand what a particular plugin does when its is executed through the sosreport command.

  • Check the source of sos package that provides sosreport command.
    For a specific version of source code, see downloads section on Customer Portal.

  • Check sos.log file in the sosreport. For example, for plugin scsi there would be something similar to as shown below

    -- directories and files collected --

2020-07-30 11:04:53,632 INFO: [plugin:scsi] collecting path '/sys/bus/scsi'
2020-07-30 11:04:53,656 INFO: [plugin:scsi] collecting path '/sys/class/scsi_disk'
2020-07-30 11:04:53,663 INFO: [plugin:scsi] collecting path '/proc/scsi'
2020-07-30 11:04:53,666 INFO: [plugin:scsi] collecting path '/sys/class/scsi_generic'
2020-07-30 11:04:53,675 INFO: [plugin:scsi] collecting path '/sys/class/scsi_host'
2020-07-30 11:04:53,677 INFO: [plugin:scsi] collecting path '/sys/class/scsi_device'

-- these were the commands executed in the background --

2020-07-30 11:04:53,686 INFO: [plugin:scsi] collecting output of 'lsscsi -i'
2020-07-30 11:04:53,710 INFO: [plugin:scsi] collecting output of 'sg_map -x'
2020-07-30 11:04:53,765 INFO: [plugin:scsi] collecting output of 'udevadm info -a /sys/class/scsi_host/host3'
2020-07-30 11:04:53,789 INFO: [plugin:scsi] collecting output of 'udevadm info -a /sys/class/scsi_host/host1'

  • Generate the sosreport only with that particular plugin and check the files and directories and the output of the commands in the collected archive.
    To generate the sosreport with particular plugin, do

    # sosreport -o plugin-name

  • To see the list of plugins, do

    # sosreport -l
  • Component
  • sos

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