Injecting messages to /dev/kmsg don't get logged to disk on RHEL6 Realtime kernels
Issue
-
The
/dev/kmsgdevice can be used to write to the kernel buffer -
On the normal RHEL6 kernels, you can "echo test > /dev/kmsg" and "test" will end up in
/var/log/kernelor/var/log/messages(wherever configured). -
On the Realtime kernels, this doesn't work. The message ends up in the kernel buffer according to "dmesg" but never gets logged to disk.
[root@ibm-x3550m4-7 log]# echo testkmsg > /dev/kmsg
[root@ibm-x3550m4-7 log]# dmesg|tail -1
testkmsg
[root@ibm-x3550m4-7 log]# grep testkmsg /var/log/*
Environment
Red Hat Enterprise Linux 6
Realtime kernels
rsyslog
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