Backup failing with err -5 - Input/output error

[rubylaser]

I am trying to migrate all of my KVM virtual machines off a Proxmox 3.4 host to new hardware that is a 4.4 host. I have migrated all of my vms except one. I have a Windows 7 virtual machine that the backup fails everytime at 9%. This is a vm with an 80GB hard drive in RAW format (LVM storage on a hardware RAID5).

The new 4.4 host is ZFS backed. The Synology storage volume is shared via NFS and has over 7TB available (all of my other machines backed up and restored from this volume with no issues. Attempts to backup to the local storage fail as well at the same 9% value (this volume has 800GB+ available).

Here is what the output looks like. Any ideas or help are greatly appreciated.

INFO: starting new backup job: vzdump 123 --remove 0 --mode snapshot --compress lzo --storage Synology --node proxmox
INFO: Starting Backup of VM 123 (qemu)
INFO: status = stopped
INFO: update VM 123: -lock backup
INFO: backup mode: stop
INFO: ionice priority: 7
INFO: creating archive '/mnt/pve/Synology/dump/vzdump-qemu-123-2017_02_08-17_00_46.vma.lzo'
INFO: starting kvm to execute backup task
INFO: started backup task 'c41d0fae-dcb5-4cc2-9d1a-f086d0561e11'
INFO: status: 0% (227934208/86008397824), sparse 0% (85282816), duration 3, 75/47 MB/s
INFO: status: 1% (878051328/86008397824), sparse 0% (114360320), duration 14, 59/56 MB/s
INFO: status: 2% (1769472000/86008397824), sparse 0% (128028672), duration 29, 59/58 MB/s
INFO: status: 3% (2631794688/86008397824), sparse 0% (152227840), duration 43, 61/59 MB/s
INFO: status: 4% (3458990080/86008397824), sparse 0% (170582016), duration 93, 16/16 MB/s
INFO: status: 5% (4304601088/86008397824), sparse 0% (185667584), duration 110, 49/48 MB/s
INFO: status: 6% (5182193664/86008397824), sparse 0% (193196032), duration 124, 62/62 MB/s
INFO: status: 7% (6074925056/86008397824), sparse 0% (202772480), duration 138, 63/63 MB/s
INFO: status: 8% (6936985600/86008397824), sparse 0% (216662016), duration 182, 19/19 MB/s
INFO: status: 9% (7792164864/86008397824), sparse 0% (258584576), duration 204, 38/36 MB/s
INFO: status: 9% (7935229952/86008397824), sparse 0% (259641344), duration 213, 15/15 MB/s
ERROR: job failed with err -5 - Input/output error
INFO: aborting backup job
INFO: stopping kvm after backup task
ERROR: Backup of VM 123 failed - job failed with err -5 - Input/output error
INFO: Backup job finished with errors
TASK ERROR: job errors

 

[rubylaser]

As another option, I guess I could do this transfer by hand to the new host. I would just like to figure this out as I've never had a Proxmox backup fail like this before.