<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> <HTML> <HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> <META NAME="Generator" CONTENT="MS Exchange Server version 6.5.7652.24"> <TITLE>RE: [Libvir] PATCH: Create a logfile for each QEMU vm</TITLE> </HEAD> <BODY>  "If QEMU fails during startup" ... please tell me how to start QEMU as a service! Thanks, smoyer -----Original Message----- From: libvir-list-bounces@redhat.com on behalf of Daniel P. Berrange Sent: Tue 5/15/2007 6:27 PM To: Mark McLoughlin Cc: libvir-list@redhat.com Subject: Re: [Libvir] PATCH: Create a logfile for each QEMU vm On Tue, May 15, 2007 at 06:37:40PM +0100, Daniel P. Berrange wrote: > On Tue, May 15, 2007 at 05:15:04PM +0100, Daniel P. Berrange wrote: > > On Tue, May 15, 2007 at 05:09:56PM +0100, Mark McLoughlin wrote: > > > On Tue, 2007-05-15 at 17:04 +0100, Daniel P. Berrange wrote: > > > > > > > For every VM we start it will create a logfile > > > > > > > > /etc/libvirt/qemu/logs/[vmname].log > > > > > > Why not /var/log? /etc/ isn't the place for this kind of stuff, surely. > > > > True - though we'd have to code different behaviour when running as an > > unprivileged user. Shouldn't complicate things too much i guess. > > Attached a new version which does this. If using qemu:///system they get > put into /var/log/libvirt/qemu, while if using qemu://session they go into > $HOME/.libvirt/qemu/log Ok, attached is my final version. - qemu:///system per-VM logs are created in /var/log/libvirt/qemu/[vmname].log - qemu:///session per-VM logs are created in $HOME/.libvirt/qemu/log/[vmname].log - The exact QEMU command line argv is logged in aforementioned files - All data written to stderr/out by QEMU is logged in aforementioned files - There is a qemudValidateConfig() method we call before starting a VM which checks the path for kernel, initrd, each disk, and any script given for a network device setup. - The horrible 'End-of-file while reading PTY startup output' is replaced with less horrible 'QEMU quit during console startup'. Though I might reword that a little more - If QEMU fails during startup, we capture the contents of stderr and include them in the libvirt error message reported. I'm not entirely happy with this because this can make messages quite verbose, but at the same time we really need to feed this info back to the user. This is even more important with remote management where there's no easy access to log files. So, here's some examples: - Starting a guest with mem set to 8 G - in this case QEMU provides zero useful error message, so we get the generic: # virsh --connect qemu:///system start wizz libvir: QEMU error : internal error QEMU shutdown while reading console startup output error: Failed to start domain wizz - Starting a guest with mem set to 1.9 G - this this case there is not enough free ram: # virsh --connect qemu:///system start wizz libvir: QEMU error : internal error QEMU shutdown while reading console startup output You do not have enough space in '/dev/shm' for the 1503 MB of QEMU virtual RAM. To have more space available provided you have enough RAM and swap, do as root: umount /dev/shm mount -t tmpfs -o size=1519m none /dev/shm Or disable the accelerator module with -no-kqemu error: Failed to start domain wizz - Starting a guest with a disk which doesn't exist: # virsh --connect qemu:///system start wizz libvir: QEMU error : internal error Cannot access disk hda at /home/berrange/src/xen/virtinst--devel/demo2: No such file or directory error: Failed to start domain wizz Regards, Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: <A HREF="http://search.cpan.org/~danberr/">http://search.cpan.org/~danberr/</A> -=| |=- Projects: <A HREF="http://freshmeat.net/~danielpb/">http://freshmeat.net/~danielpb/</A> -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=| </BODY> </HTML>