Installation guide

In vest ig at io n
By default, migration only transfers the in-memory state of a running guest (such as
memory or CPU state). Although disk images are not transferred during migration, they
need to remain accessible at the same path by both hosts.
So lu t io n
Set up and mount shared storage at the same location on both hosts. The simplest way to
do this is to use NFS:
Pro ced u re B.5. Set t in g u p sh ared st orag e
1. Set up an NFS server on a host serving as shared storage. The NFS server can be
one of the hosts involved in the migration, as long as all hosts involved are
accessing the shared storage through NFS.
# mkdir -p /exports/images
# cat >>/etc/exports <<EOF
/exports/images 192.168.122.0/24(rw,no_root_squash)
EOF
2. Mount the exported directory at a common location on all hosts running lib virt . For
example, if the IP address of the NFS server is 192.168.122.1, mount the directory
with the following commands:
# cat >>/etc/fstab <<EOF
192.168.122.1:/exports/images /var/lib/libvirt/images nfs
auto 0 0
EOF
# mount /var/lib/libvirt/images
Note
It is not possible to export a local directory from one host using NFS and mount it at
the same path on another host — the directory used for storing disk images must be
mounted from shared storage on both hosts. If this is not configured correctly, the
guest virtual machine may lose access to its disk images during migration, because
the source host's lib virt daemon may change the owner, permissions, and SELinux
labels on the disk images after it successfully migrates the guest to its destination.
If lib virt detects that the disk images are mounted from a shared storage location, it
will not make these changes.
B.15. No guest virt ual machines are present when libvirt d is st art ed
Symp t o m
The lib virt daemon is successfully started, but no guest virtual machines appear to be
present.
Common libvirt errors and t roublesh oot ing
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