Re: [libvirt] Domain XML isn't dumping full backing chain

----- Original Message ----- | From: "Deepak Shetty" <dpkshetty(a)gmail.com&gt; | To: libvir-list(a)redhat.com | Sent: Wednesday, March 18, 2015 7:19:05 PM | Subject: [libvirt] Domain XML isn't dumping full backing chain | Hi, | I am using libvirt version 1.2.9.2 on F21 and i am unable to get the complete | backing chain info in the virsh dumpxml output. Details below : | My backing chain per qemu-img : | [stack@devstack-f21 test]$ qemu-img info --backing-chain snap4.qcow2 | image: snap4.qcow2 | file format: qcow2 | virtual size: 1.0G (1073741824 bytes) | disk size: 196K | cluster_size: 65536 | backing file: ./snap3.qcow2 | Format specific information: | compat: 1.1 | lazy refcounts: false | image: ./snap3.qcow2 | file format: qcow2 | virtual size: 1.0G (1073741824 bytes) | disk size: 196K | cluster_size: 65536 | backing file: ./snap2.qcow2 (actual path: ././snap2.qcow2) | Format specific information: | compat: 1.1 | lazy refcounts: false | image: ././snap2.qcow2 | file format: qcow2 | virtual size: 1.0G (1073741824 bytes) | disk size: 196K | cluster_size: 65536 | backing file: ./snap1.qcow2 (actual path: ./././snap1.qcow2) | Format specific information: | compat: 1.1 | lazy refcounts: false | image: ./././snap1.qcow2 | file format: qcow2 | virtual size: 1.0G (1073741824 bytes) | disk size: 196K | cluster_size: 65536 | backing file: ./base.qcow2 (actual path: ././././base.qcow2) | Format specific information: | compat: 1.1 | lazy refcounts: false | image: ././././base.qcow2 | file format: qcow2 | virtual size: 1.0G (1073741824 bytes) | disk size: 196K | cluster_size: 65536 | Format specific information: | compat: 1.1 | lazy refcounts: false If you want prepare the backing chain yourself, you should add "-o backing_fmt=$farmat" options, like "qemu-img create -f qcow2 base.s1 -b base.qcow2 -o backing_fmt=qcow2" | I created 4 snapshots using commands (similar to the below, just dumping the | last one here ): | [stack@devstack-f21 test]$ virsh snapshot-create-as test-domain on-test-snap4 | --disk-only --reuse-external --diskspec | hda,snapshot=external,file=/home/stack/test/snap4.qcow2 | Domain snapshot on-test-snap4 created | [stack@devstack-f21 test]$ virsh domblklist test-domain | Target Source | ------------------------------------------------ | hda /home/stack/test/snap4.qcow2 | virsh dumpxml test-domain|more | .... | <disk type='file' device='disk'> | <driver name='qemu' type='qcow2' cache='none'/> | <source file='/home/stack/test/snap4.qcow2'/> | <backingStore type='file' index='1'> | <format type='raw'/> If you don't add "-o backing_fmt=qcow2", it will treat backing file format as raw format. Since a raw format file doesn't have a backing file, so you only see snap4.qcow2 and snap3.qcow2 | <source file='/home/stack/test/./snap3.qcow2'/> | <backingStore/> | </backingStore> | <target dev='hda' bus='ide'/> | <alias name='ide0-0-0'/> | <address type='drive' controller='0' bus='0' target='0' unit='0'/> | </disk> | ..... | I think thats happening beccause the backingStore format is coming as 'raw' | What am i missing ? | thanx, | deepak | -- | libvir-list mailing list | libvir-list(a)redhat.com | https://www.redhat.com/mailman/listinfo/libvir-list -- Regards shyu