09-08-2015 01:11 AM
Hi Experts,
I have one linux red hat client v7.7 and there is /var/images/hpg82 which is used to save the related files of my KVM.
I want to know the detailed impact if I do standard backup with /var/images/hpg82 while the VM is running.
[root@xun bin]# virsh list --all
Id Name State
----------------------------------------------------
4 hpg82 running
[root@xun bin]# cd /var/images/hpg82
[root@xun hpg82]# ll
total 6305536
-rw-------. 1 root root 376832 Sep 7 16:17 configdrive.iso
-rw-------. 1 root root 200704 Sep 7 16:18 datadisk.qcow2
-rw-------. 1 root root 6456344576 Sep 7 16:18 rhel.qcow2
-rw-------. 1 root root 2845 Sep 7 16:17 vmdomain.xml
[root@xun hpg82]#
Regards,
Lacey
Solved! Go to Solution.
09-08-2015 04:36 AM
The data inside the KVM VM will be in-consistent.
If the VM is idle it may just work, but on a highly busy system expect to have a lot of maybe un-repairable file system inconsistencies.
Only way to ensure data is 100% valid is to stop the VM during backup.
Alternative - investigate if KVM has snapshot functationality. Found this - says QEMU - don't know if this is the same as KVM
09-08-2015 04:36 AM
The data inside the KVM VM will be in-consistent.
If the VM is idle it may just work, but on a highly busy system expect to have a lot of maybe un-repairable file system inconsistencies.
Only way to ensure data is 100% valid is to stop the VM during backup.
Alternative - investigate if KVM has snapshot functationality. Found this - says QEMU - don't know if this is the same as KVM
09-08-2015 04:40 AM
Don't know KVM, but assume that you need to make a snapshot of the VM and take backup of that or install a client inside the VM to have a consistent backup . That is the options on other virtualization systems like VMWARE and Hyper-V.
09-08-2015 06:55 PM
Do you mean that Symantec NetBackup uses QEMU command to backup *.qcow2 files?
09-08-2015 08:34 PM