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Unable to get kernel log messages written to a specific log file on syslog server

pl flag

I have a working rsyslog setup with CentOS as my server and I am using Kali as the client.

I am able to use logger on Kali to send test log messages and see the log messages appear in the CentOS messages file and in the facility specific files I have setup in /var/log. All with the exception of kernel messages.

I see kernel messages appear in the messages file on CentOS, but it does not write to the kernel.log file I have in /var/log.

From this I deduce that the Kali client sends the log message correctly (as it is received and present in the messages file), but I am missing something in the rsyslog.conf file on CentOS.

This is what I use to generate a log message from Kali:

logger -t "new test" -p kern.err "testing kernel log messages"

I do a tail -f messages on CentOS and the log message appears. However, when I cat the kernel.log file, it is empty.

This is what I have for rsyslog.conf on the CentOS machine. Any advice is welcome.

Here is the full rsyslog.conf file


# rsyslog configuration file

# For more information see /usr/share/doc/rsyslog-*/rsyslog_conf.html
# If you experience problems, see http://www.rsyslog.com/doc/troubleshoot.html

#### MODULES ####

# The imjournal module bellow is now used as a message source instead of imuxsock.
$ModLoad imuxsock # provides support for local system logging (e.g. via logger command)
$ModLoad imjournal # provides access to the systemd journal
$ModLoad imklog # reads kernel messages (the same are read from journald)
$ModLoad immark  # provides --MARK-- message capability

# Provides UDP syslog reception
#$ModLoad imudp
#$UDPServerRun 514

# Provides TCP syslog reception
$ModLoad imtcp
$InputTCPServerRun 514


#### GLOBAL DIRECTIVES ####

# Where to place auxiliary files
$WorkDirectory /var/lib/rsyslog

# Use default timestamp format
$ActionFileDefaultTemplate RSYSLOG_TraditionalFileFormat

# File syncing capability is disabled by default. This feature is usually not required,
# not useful and an extreme performance hit
#$ActionFileEnableSync on

# Include all config files in /etc/rsyslog.d/
$IncludeConfig /etc/rsyslog.d/*.conf

# Turn off message reception via local log socket;
# local messages are retrieved through imjournal now.
$OmitLocalLogging on

# File to store the position in the journal
$IMJournalStateFile imjournal.state


#### RULES ####

# Log all kernel messages to the console.
# Logging much else clutters up the screen.
kern.info                                                  /var/log/kernel.log
# Log anything (except mail) of level info or higher.
# Don't log private authentication messages!
*.info;mail.none;authpriv.none;cron.none                /var/log/messages
kern.err                        /var/log/kernel.log
# The authpriv file has restricted access.
authpriv.*                                              /var/log/secure

# Log all the mail messages in one place.
mail.*                                                  /var/log/maillog
#log lpr message to a file
#lpr.*                          /var/log/lpr.log

# Log cron stuff
cron.*                                                  /var/log/cron

# Everybody gets emergency messages
*.emerg                                                 :omusrmsg:*

# Save news errors of level crit and higher in a special file.
uucp,news.crit                                          /var/log/spooler

# Save boot messages also to boot.log
local7.*                                                /var/log/boot.log


# ### begin forwarding rule ###
# The statement between the begin ... end define a SINGLE forwarding
# rule. They belong together, do NOT split them. If you create multiple
# forwarding rules, duplicate the whole block!
# Remote Logging (we use TCP for reliable delivery)
#
# An on-disk queue is created for this action. If the remote host is
# down, messages are spooled to disk and sent when it is up again.
#$ActionQueueFileName fwdRule1 # unique name prefix for spool files
#$ActionQueueMaxDiskSpace 1g   # 1gb space limit (use as much as possible)
#$ActionQueueSaveOnShutdown on # save messages to disk on shutdown
#$ActionQueueType LinkedList   # run asynchronously
#$ActionResumeRetryCount -1    # infinite retries if host is down
# remote host is: name/ip:port, e.g. 192.168.0.1:514, port optional
#*.* @@remote-host:514
# ### end of the forwarding rule ###

Chris Lewis avatar
pl flag
Thank you @mforsetti for the formatting improvements
mforsetti avatar
tz flag
sure, no problem. back on topic, can you dump the whole `rsyslogd` config with `sudo rsyslog -o -` and include it (copy and paste, not a screenshot) in your question?
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