acrnlog is a userland tool used to capture a ACRN hypervisor log. It runs as an
SOS service at boot, capturing two kinds of logs:
- log of the currently running hypervisor
- log of last running hypervisor if it crashed and the logs remain.
Log files are saved in
/tmp/acrnlog/, so the log files would be lost
after a system reset.
acrnlog tool is launched as a service at boot, and limited to
supporting four 1MB log files by default. You can change this log file
limitation temporarily or permanently.
-h display help -t specify a polling interval (ms). Once buffer is empty, acrnlog stops and starts reading in specified interval. If an incomplete log warning is reported, please try with a smaller interval to get a complete log. -s limit the size of each log file, in KB. 0 means no limitation. -n specify the number of log files to keep, old files would be deleted.
Temporary log file changes¶
You can temporarily change the log file setting by following these steps:
# systemctl disable acrnlog
acrnlog, running in the background, and specify the new number of log files and their size (in MB). For example:
# acrnlog -n 8 -s 4 &
You can use
loglevel command in the hypervisor shell (not the Service
OS shell) to query and change the hypervisor log level.
mem_loglevel parameter controls the log to be saved using
acrnlog, while the
console_loglevel parameter controls the log
output to the console. For example, in the hypervisor shell you
can use these commands:
ACRN:\>loglevel console_loglevel: 3, mem_loglevel: 5, npk_loglevel: 5 ACRN:\>loglevel 2 5 ACRN:\>loglevel console_loglevel: 2, mem_loglevel: 5, npk_loglevel: 5
Permanent log file changes¶
You can also permanently change the log file settings by
/usr/lib/systemd/system/acrnlog.service and use the
-s options on the
ExecStart cmd, and restart the service.
acrnlog.service could have these parameters added:
ExecStart=/usr/bin/acrnlog -n 8 -s 4
and then restart the service with:
# systemctl daemon-reload # systemctl restart acrnlog
Build and Install¶
Source code for the
acrnlog tools is in the
folder. Build and install the tools from source using:
# make # make install
and if you changed the
acrnlog.service file, install it using:
# cp acrnlog.service /usr/lib/systemd/system/