Installation guide

Nearly all new BIOSes allow enabling or disabling of the No eXecute bit. However, if
disabled, some CPUs do not report this flag and thus lib virt detects a different CPU.
Enabling this functionality instructs lib virt to report the correct CPU. Refer to your
hardware documentation for further instructions on this subject.
B.4 . Guest st art ing fails wit h error: mo ni to r so cket d i d no t sho w up
Symp t o m
The guest virtual machine (or domain) starting fails with this error (or similar):
# virsh -c qemu:///system create name_of_guest.xml error: Failed
to create domain from name_of_guest.xml error: monitor socket did
not show up.: Connection refused
In vest ig at io n
This error message shows:
1. lib virt is working;
2. The Q EMU process failed to start up; and
3. lib virt quits when trying to connect Q EMU or the QEMU agent monitor socket.
To understand the error details, examine the guest log:
# cat /var/log/libvirt/qemu/name_of_guest.log
LC_ALL=C PATH=/sbin:/usr/sbin:/bin:/usr/bin QEMU_AUDIO_DRV=none
/usr/bin/qemu-kvm -S -M pc -enable-kvm -m 768 -smp
1,sockets=1,cores=1,threads=1 -name name_of_guest -uuid ebfaadbe-
e908-ba92-fdb8-3fa2db557a42 -nodefaults -chardev
socket,id=monitor,path=/var/lib/libvirt/qemu/name_of_guest.monito
r,server,nowait -mon chardev=monitor,mode=readline -no-reboot -
boot c -kernel /var/lib/libvirt/boot/vmlinuz -initrd
/var/lib/libvirt/boot/initrd.img -append
method=http://www.example.com/pub/product/release/version/x86_64/
os/ -drive
file=/var/lib/libvirt/images/name_of_guest.img,if=none,id=drive-
ide0-0-0,boot=on -device ide-drive,bus=ide.0,unit=0,drive=drive-
ide0-0-0,id=ide0-0-0 -device virtio-net-
pci,vlan=0,id=net0,mac=52:40:00:f4:f1:0a,bus=pci.0,addr=0x4 -net
tap,fd=42,vlan=0,name=hostnet0 -chardev pty,id=serial0 -device
isa-serial,chardev=serial0 -usb -vnc 127.0.0.1:0 -k en-gb -vga
cirrus -device virtio-balloon-pci,id=balloon0,bus=pci.0,
addr=0x3
char device redirected to /dev/pts/1
qemu: could not load kernel '/var/lib/libvirt/boot/vmlinuz':
Permission denied
So lu t io n
The guest log contains the details needed to fix the error.
If a host is shut down while the guest is still running a lib virt version prior to 0.9.5, the
libvirt-guest's init script attempts to perform a managed save of the guest. If the managed
Common libvirt errors and t roublesh oot ing
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