F #2095 Support persistant VM snapshots for kvm

share/etc/oned.conf

@@ -566,7 +566,7 @@ VM_MAD = [
     ARGUMENTS      = "-t 15 -r 0 kvm",
     DEFAULT        = "vmm_exec/vmm_exec_kvm.conf",
     TYPE           = "kvm",
-    KEEP_SNAPSHOTS = "no",
+    KEEP_SNAPSHOTS = "yes",
     IMPORTED_VMS_ACTIONS = "terminate, terminate-hard, hold, release, suspend,
         resume, delete, reboot, reboot-hard, resched, unresched, disk-attach,
         disk-detach, nic-attach, nic-detach, snapshot-create, snapshot-delete"

src/vmm/LibVirtDriverKVM.cc

@@ -1472,9 +1472,11 @@ int LibVirtDriver::deployment_description_kvm(
     // Metadata used by drivers
     // ------------------------------------------------------------------------
     file << "\t<metadata>\n"
-         << "\t\t<system_datastore>"
+         << "\t\t<one:vm xmlns:one=\"http://opennebula.org/xmlns/libvirt/1.0\">\n"
+         << "\t\t\t<one:system_datastore>"
          << one_util::escape_xml(vm->get_system_dir())
-         << "</system_datastore>\n"
+         << "</one:system_datastore>\n"
+         << "\t\t</one:vm>\n"
         // << "\t\t<opennebula>\n" << vm->to_xml(vm_xml) << "\t\t</opennebula>\n"
          << "\t</metadata>\n";
 

src/vmm_mad/remotes/kvm/deploy

@@ -19,16 +19,33 @@
 source $(dirname $0)/../../etc/vmm/kvm/kvmrc
 source $(dirname $0)/../../scripts_common.sh
 
-domain=$1
+DEP_FILE=$1
+DEP_FILE_LOCATION=$(dirname $DEP_FILE)
 
-mkdir -p `dirname $domain`
-cat > $domain
+mkdir -p $DEP_FILE_LOCATION
+cat > $DEP_FILE
 
-data=`virsh --connect $LIBVIRT_URI create $domain`
+DATA=`virsh --connect $LIBVIRT_URI create $DEP_FILE`
 
 if [ "x$?" = "x0" ]; then
-    echo $data | sed 's/Domain //' | sed 's/ created from .*$//'
+
+    DOMAIN_ID=$(echo $DATA | sed 's/Domain //' | sed 's/ created from .*$//')
+    echo $DOMAIN_ID
+
+    # redefine potential snapshots
+    for SNAPSHOT_MD_XML in $(ls ${DEP_FILE_LOCATION}/snap-*.xml 2>/dev/null); do
+
+        # query UUID, but only once
+        UUID=${UUID:-$(virsh --connect $LIBVIRT_URI dominfo $DOMAIN_ID | grep UUID: | awk '{print $2}')}
+
+        # replace uuid in the snapshot metadata xml
+        sed -i "s%<uuid>[[:alnum:]-]*</uuid>%<uuid>$UUID</uuid>%" $SNAPSHOT_MD_XML
+
+        # redefine the snapshot using the xml metadata file
+        virsh --connect $LIBVIRT_URI snapshot-create $DOMAIN_ID $SNAPSHOT_MD_XML --redefine > /dev/null || true
+    done
+
 else
-    error_message "Could not create domain from $domain"
+    error_message "Could not create domain from $DEP_FILE"
     exit -1
 fi

src/vmm_mad/remotes/kvm/kvmrc

@@ -20,6 +20,9 @@ export LIBVIRT_URI=qemu:///system
 
 export QEMU_PROTOCOL=qemu+ssh
 
+export LIBVIRT_MD_URI=http://opennebula.org/xmlns/libvirt/1.0
+export LIBVIRT_MD_KEY=one
+
 # Seconds to wait after shutdown until timeout
 export SHUTDOWN_TIMEOUT=300
 

src/vmm_mad/remotes/kvm/snapshot_create

@@ -22,9 +22,36 @@ source $(dirname $0)/../../scripts_common.sh
 DOMAIN="$1"
 SNAP_ID="$2"
 
-data=`virsh --connect $LIBVIRT_URI snapshot-create-as $DOMAIN --name "snap-${SNAP_ID}"`
+# -------- Get datastore location from libvirt metadata ------------
+
+DRIVER_PATH=$(dirname $0)
+XPATH="${DRIVER_PATH}/../../datastore/xpath.rb --stdin"
+
+METADATA_XML=`virsh --connect $LIBVIRT_URI metadata $DOMAIN $LIBVIRT_MD_URI $LIBVIRT_MD_KEY`
+
+unset i XPATH_ELEMENTS
+
+while IFS= read -r -d '' element; do
+    XPATH_ELEMENTS[i++]="$element"
+done < <(echo "$METADATA_XML" | $XPATH /vm/system_datastore/)
+
+unset i
+
+DATASTORE_PATH="${XPATH_ELEMENTS[i++]}"
+
+
+# -------- Create the snapshot and dump its metadata to xml file ------------
+
+SNAP_NAME="snap-${SNAP_ID}"
+data=`virsh --connect $LIBVIRT_URI snapshot-create-as $DOMAIN --name "$SNAP_NAME"`
 
 if [ "$?" = "0" ]; then
+
+    SNAP_XML_PATH="${DATASTORE_PATH}/${SNAP_NAME}.xml"
+
+    # dump snapshot metadata xml to the VM location
+    virsh --connect $LIBVIRT_URI snapshot-dumpxml $DOMAIN $SNAP_NAME > $SNAP_XML_PATH || true
+
     echo "$data" | awk '{print $3}'
 else
     error_message "Could not create snapshot $NAME for domain $DOMAIN."

src/vmm_mad/remotes/kvm/snapshot_delete

@@ -22,6 +22,28 @@ source $(dirname $0)/../../scripts_common.sh
 DOMAIN="$1"
 NAME="$2"
 
+# -------- Get datastore location from libvirt metadata ------------
+
+DRIVER_PATH=$(dirname $0)
+XPATH="${DRIVER_PATH}/../../datastore/xpath.rb --stdin"
+
+METADATA_XML=`virsh --connect $LIBVIRT_URI metadata $DOMAIN $LIBVIRT_MD_URI $LIBVIRT_MD_KEY`
+
+unset i XPATH_ELEMENTS
+
+while IFS= read -r -d '' element; do
+    XPATH_ELEMENTS[i++]="$element"
+done < <(echo "$METADATA_XML" | $XPATH /vm/system_datastore/)
+
+unset i
+
+DATASTORE_PATH="${XPATH_ELEMENTS[i++]}"
+
+
+# ------ Delete snapshot metadata and the snapshot itself ----------
+
+rm ${DATASTORE_PATH}/${NAME}.xml 2>/dev/null || true
+
 exec_and_log \
     "virsh --connect $LIBVIRT_URI snapshot-delete $DOMAIN $NAME" \
     "Could not delete snapshot $NAME for domain $DOMAIN."