Installation guide

save was incomplete (for example, due to loss of power before the managed save image

was flushed to disk), the save image is corrupted and will not be loaded by Q EMU . The

older version of libvirt does not recognize the corruption, making the problem perpetual. In

this case, the guest log will show an attempt to use -i nco mi ng as one of its arguments,

meaning that lib virt is trying to start Q EMU by migrating in the saved state file.

This problem can be fixed by running vi rsh manag ed save-remo ve name_of_guest to

remove the corrupted managed save image. Newer versions of libvirt take steps to avoid

the corruption in the first place, as well as adding vi rsh start --fo rce-bo o t

name_of_guest to bypass any managed save image.

B.5. Internal erro r canno t fi nd character d evi ce (nul l )

Symp t o m

This error message appears when attempting to connect to a guest virtual machine's

console:

# virsh console test2 Connected to domain test2 Escape character

is ^] error: internal error cannot find character device (null)

In vest ig at io n

This error message shows that there is no serial console configured for the guest virtual

machine.

So lu t io n

Set up a serial console in the guest's XML file.

Pro ced u re B.1. Set t in g u p a serial co n so le in t h e g u est ' s XML

1. Add the following XML to the guest virtual machine's XML using virsh ed it :

</serial>

</console>

2. Set up the console in the guest kernel command line.

To do this, either log in to the guest virtual machine to edit the

/bo o t/g rub/g rub. co nf file directly, or use the virt - ed it command line tool. Add

the following to the guest kernel command line:

console=ttyS0,115200

3. Run the followings command:

# virsh start vm & & virsh console vm

B.6. Guest virt ual machine boot ing st alls wit h error: No bo o t d evi ce

Red Hat Ent erp rise Linux 6 Virt ualiz at ion Host Configurat ion and G uest Inst allat ion G uide

134