Editing KVM: Create Live backups (snapshot-create-as, blockcommit)

Reference document: https://wiki.libvirt.org/page/Live-disk-backup-with-active-blockcommit

* Overview: <code>[[virsh snapshot-create-as]]</code> -> <code>[[cp]]/[[rsync]]</code> -> <code>[[virsh blockcommit]]</code>



1. Create an external disk snapshot, specify image destination :

<code>[[virsh snapshot-create-as]] --domain VM_TO_BACKUP --diskspec vda,file=/export/images/VM_TO_BACKUP_overlay1.qcow2 --disk-only --atomic</code>
:<code>--diskspec</code>  To indicate '''external snapshot''' and location
:<code>--disk-only</code> Do not save memory information
:<code>--atomic</code>

2. Take a backup of the '''original disk''': <code>[[cp]]</code> or <code>[[rsync]]</code>

3. <code>[[virsh blockcommit]] VM_TO_BACKUP DEVICE_TARGET --active --verbose --pivot</code>
:<code>[[virsh blockcommit]] VM_TO_BACKUP vda --active --verbose --pivot</code> (--wait)


== Related terms ==
* <code>[[virsh domblklist]] VM_NAME --details</code>
* <code>[[virsh dumpxml]]</code>
* <code>[[virsh vol-list]] POOL_NAME --details</code>
* [[Error: unsupported configuration: external snapshot file for disk vda already exists and is not a block device]]

== Activities ==
# Review [[Bash]] script https://gist.github.com/cabal95/e36c06e716d3328b512b implementing Live Backup and https://gist.github.com/maxim-gorkin/f0e8a2c01a93ca65ad2ad10566a78d72 with [[logging]] capabilities, remote destination and rsync usage.
# Review [[bacula]] solution: http://www.bacula.lat/kvm-hot-online-virtual-machines-backup-with-bacula-bpipe/?lang=en
# Review Veritas [[Netbackup]] support for [[Red Hat Virtualization|RHV]]
# View [[Eric Blacke]] video: https://www.youtube.com/watch?v=zQK5ANionpU

== See also ==
* {{virsh snapshot}}
* {{virsh block}}
* {{KVM}}


[[Category:Linux]]
[[Category:KVM]]