I had a qemu virtual-machine which crashed several times because HDD in hypervisor had no space left. This made me wonder is there a possibility to to set up a logging/debugging for quemu virtual-machines. I tried to start virtual-machine with -D /tmp/qemu-debug-log command:qemu-system-i386 -D /tmp/qemu-debug-log -monitor pty -device e1000,netdev=tap0 -netdev tap,id=tap0 -m 512M -display vnc=:1 -drive file=FreeBSD10.2..but this did not even create a /tmp/qemu-debug-log file.In addition, qemu does not seem to write into messages or kernel ring buffer(dmesg). What are the best practices to enable logging for qemu virtual machines?
logging and debugging for qemu virtual machines
qemu
qemu command accepts a simple -d switch which creates a log file called /tmp/qemu.log.You can access more logging/debugging options via  QEMU Monitor (e.g. qemu -monitor stdio).