Linux dmesg –follow (-w) not working?
Thursday, Apr 30, 2020
For a couple months now, I have noticed that running dmesg -w on my workstation does not appear to print out new kernel messages. In other words dmesg --follow “hangs”. Additionally when running tail -f /var/log/kern.log to monitor new dmesg messages picked up by sysklogd (part of syslogng), the latest messages do not come through until sysklogd periodically “reopens” the /dev/kmsg kernel message buffer. Why is this a problem? This is a problem because I use the dmesg log to monitor important hardware related messages such as the kernel recognizing a USB device or diagnosing bluetooth/wifi issues.