Failing backups with same vms on different nodes.

[ozgurerdogan]

104: Oct 30 04:51:46 ERROR: VM 104 qmp command 'query-backup' failed - got timeout
104: Oct 30 04:51:46 INFO: aborting backup job
104: Oct 30 05:01:46 ERROR: VM 104 qmp command 'backup-cancel' failed - unable to connect to VM 104 qmp socket - timeout after 5984 retries
104: Oct 30 05:01:53 ERROR: Backup of VM 104 failed - VM 104 qmp command 'query-backup' failed - got timeout

Why is this happening? Should reinstall node? Or move vm to other node? Because after failing backup I have to restart node. Otherwise it does not start.

pve-kernel-4.4.21-1-pve: 4.4.21-70
pve-kernel-4.4.15-1-pve: 4.4.15-60
pve-kernel-4.2.8-1-pve: 4.2.8-41
pve-kernel-4.4.19-1-pve: 4.4.19-66
pve-kernel-4.4.10-1-pve: 4.4.10-54
lvm2: 2.02.116-pve3
corosync-pve: 2.4.0-1
libqb0: 1.0-1
pve-cluster: 4.0-46
qemu-server: 4.0-92
pve-firmware: 1.1-10
libpve-common-perl: 4.0-76
libpve-access-control: 4.0-19
libpve-storage-perl: 4.0-67
pve-libspice-server1: 0.12.8-1
vncterm: 1.2-1
pve-docs: 4.3-12
pve-qemu-kvm: 2.7.0-4
pve-container: 1.0-78
pve-firewall: 2.0-31
pve-ha-manager: 1.0-35
ksm-control-daemon: 1.2-1
glusterfs-client: 3.5.2-2+deb8u2
lxc-pve: 2.0.5-1
lxcfs: 2.0.4-pve2
criu: 1.6.0-1
novnc-pve: 0.5-8
smartmontools: 6.5+svn4324-1~pve80
zfsutils: 0.6.5.8-pve12~bpo80