abh1sar commented on code in PR #12991: URL: https://github.com/apache/cloudstack/pull/12991#discussion_r3179593201
########## plugins/hypervisors/kvm/src/main/java/com/cloud/hypervisor/kvm/resource/wrapper/LibvirtStartBackupCommandWrapper.java: ########## @@ -0,0 +1,221 @@ +//Licensed to the Apache Software Foundation (ASF) under one +//or more contributor license agreements. See the NOTICE file +//distributed with this work for additional information +//regarding copyright ownership. The ASF licenses this file +//to you under the Apache License, Version 2.0 (the +//"License"); you may not use this file except in compliance +//the License. You may obtain a copy of the License at +// +//http://www.apache.org/licenses/LICENSE-2.0 +// +//Unless required by applicable law or agreed to in writing, +//software distributed under the License is distributed on an +//"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +//KIND, either express or implied. See the License for the +//specific language governing permissions and limitations +//under the License. + +package com.cloud.hypervisor.kvm.resource.wrapper; + +import java.io.File; +import java.io.FileWriter; +import java.util.Map; + +import org.apache.cloudstack.backup.StartBackupAnswer; +import org.apache.cloudstack.backup.StartBackupCommand; +import org.apache.logging.log4j.Logger; +import org.apache.logging.log4j.LogManager; +import com.cloud.agent.api.Answer; +import com.cloud.hypervisor.kvm.resource.LibvirtComputingResource; +import com.cloud.resource.CommandWrapper; +import com.cloud.resource.ResourceWrapper; +import com.cloud.utils.StringUtils; +import com.cloud.utils.script.Script; + +@ResourceWrapper(handles = StartBackupCommand.class) +public class LibvirtStartBackupCommandWrapper extends CommandWrapper<StartBackupCommand, Answer, LibvirtComputingResource> { + protected Logger logger = LogManager.getLogger(getClass()); + + @Override + public Answer execute(StartBackupCommand cmd, LibvirtComputingResource resource) { + if (cmd.isStoppedVM()) { + return handleStoppedVmBackup(cmd, cmd.getToCheckpointId()); + } + return handleRunningVmBackup(cmd, resource); + } + + public Answer handleRunningVmBackup(StartBackupCommand cmd, LibvirtComputingResource resource) { + String vmName = cmd.getVmName(); + String toCheckpointId = cmd.getToCheckpointId(); + String fromCheckpointId = cmd.getFromCheckpointId(); + Long fromCheckpointCreateTime = cmd.getFromCheckpointCreateTime(); + String socket = cmd.getSocket(); + + try { + if (StringUtils.isNotBlank(fromCheckpointId)) { + Answer redefineAnswer = ensureFromCheckpointExists(cmd, fromCheckpointId, fromCheckpointCreateTime); + if (redefineAnswer != null) { + return redefineAnswer; + } + } + + File dir = new File("/tmp/imagetransfer"); + if (!dir.exists()) { + dir.mkdirs(); + } + + // Create backup XML + String backupXml = createBackupXml(cmd, fromCheckpointId, socket, resource); + String checkpointXml = createCheckpointXml(toCheckpointId); + + // Write XMLs to temp files + File backupXmlFile = File.createTempFile("backup-", ".xml"); + File checkpointXmlFile = File.createTempFile("checkpoint-", ".xml"); + + try (FileWriter writer = new FileWriter(backupXmlFile)) { + writer.write(backupXml); + } + try (FileWriter writer = new FileWriter(checkpointXmlFile)) { + writer.write(checkpointXml); + } + + // Execute virsh backup-begin + String backupCmd = String.format("virsh backup-begin %s %s --checkpointxml %s", + vmName, backupXmlFile.getAbsolutePath(), checkpointXmlFile.getAbsolutePath()); + + Script script = new Script("/bin/bash"); + script.add("-c"); + script.add(backupCmd); + String result = script.execute(); + + backupXmlFile.delete(); + checkpointXmlFile.delete(); + + if (result != null) { + return new StartBackupAnswer(cmd, false, "Backup begin failed: " + result); + } + + long checkpointCreateTime = getCheckpointCreateTime(); + return new StartBackupAnswer(cmd, true, "Backup started successfully", checkpointCreateTime); + + } catch (Exception e) { + return new StartBackupAnswer(cmd, false, "Error starting backup: " + e.getMessage()); + } + } + + private Answer ensureFromCheckpointExists(StartBackupCommand cmd, String fromCheckpointId, Long fromCheckpointCreateTime) { + String vmName = cmd.getVmName(); + Script dumpScript = new Script("/bin/bash"); + dumpScript.add("-c"); + dumpScript.add(String.format("virsh checkpoint-dumpxml --domain %s --checkpointname %s --no-domain", + vmName, fromCheckpointId)); + if (dumpScript.execute() == null) { + return null; + } + if (fromCheckpointCreateTime == null) { + return new StartBackupAnswer(cmd, false, "From checkpoint create time is null for checkpoint " + fromCheckpointId); + } + + String redefineXml = createCheckpointXmlForRedefine(fromCheckpointId, fromCheckpointCreateTime); + File redefineFile; + try { + redefineFile = File.createTempFile("checkpoint-redefine-", ".xml"); + } catch (Exception e) { + return new StartBackupAnswer(cmd, false, "Failed to create temp file for checkpoint redefine: " + e.getMessage()); + } + try (FileWriter writer = new FileWriter(redefineFile)) { + writer.write(redefineXml); + } catch (Exception e) { + redefineFile.delete(); + return new StartBackupAnswer(cmd, false, "Failed to write checkpoint redefine XML: " + e.getMessage()); + } + String createCmd = String.format(LibvirtComputingResource.CHECKPOINT_CREATE_COMMAND, vmName, redefineFile.getAbsolutePath()); + Script createScript = new Script("/bin/bash"); + createScript.add("-c"); + createScript.add(createCmd); + String result = createScript.execute(); + redefineFile.delete(); + if (result != null) { + return new StartBackupAnswer(cmd, false, "Failed to redefine from-checkpoint " + fromCheckpointId + ": " + result); + } + return null; + } + + private String createCheckpointXmlForRedefine(String checkpointName, Long createTime) { + StringBuilder xml = new StringBuilder(); + xml.append("<domaincheckpoint>\n"); + xml.append(" <name>").append(checkpointName).append("</name>\n"); + xml.append(" <creationTime>").append(createTime).append("</creationTime>\n"); + xml.append("</domaincheckpoint>"); + return xml.toString(); + } + + private String createBackupXml(StartBackupCommand cmd, String fromCheckpointId, String socket, LibvirtComputingResource resource) { + StringBuilder xml = new StringBuilder(); + xml.append("<domainbackup mode=\"pull\">\n"); + + if (StringUtils.isNotBlank(fromCheckpointId)) { + xml.append(" <incremental>").append(fromCheckpointId).append("</incremental>\n"); + } + + xml.append(String.format(" <server transport=\"unix\" socket=\"/tmp/imagetransfer/%s.sock\"/>\n", socket)); + + xml.append(" <disks>\n"); + + Map<String, String> diskPathUuidMap = cmd.getDiskPathUuidMap(); + Map<String, String> diskPathLabelMap = resource.getDiskPathLabelMap(cmd.getVmName()); + + for (Map.Entry<String, String> entry : diskPathLabelMap.entrySet()) { + if (!diskPathUuidMap.containsKey(entry.getKey())) { + continue; + } + String diskName = entry.getValue(); + String export = diskPathUuidMap.get(entry.getKey()); + String scratchFile = "/var/tmp/scratch-" + export + ".qcow2"; Review Comment: Scratch file grows with incoming guest writes. It is created initially with 0 blocks. If the VM tries to write to a block being backed-up, QEMU first copies the original data of that block from the VM disk into the scratch file. The max it can grow to is the size of the VM disk in the worst case. I think guest writes might stall if space is not there. But I'll test it out. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
