4.1. Image Backup

Image Backup is a service that provides features to acquire and store Virtual Server images (called “Backup Images” below) and features to restore the Virtual Server from the stored backup images.


  • You can use image backup at a Data Center that provides Compute Resource or Compute Resource (Dedicated Device). The products provided differ depending on the Data Center. For details, refer to “1.3.2 Available Data Centers”.

4.1.1. Available Features

Customer can use the following features in Image Backup.
Function Outline
Backup and Restore A feature that acquires stores and restores backup images for the purpose of backup. Backup images are stored in a storage device provided by the NTT Communications (called “Backup Storage” below). For restoration, backup images are directly overwritten on the Virtual Server.
Backup and Restore Management A feature that manages backup of the Virtual Server. It is possible to manage the schedule and check the history of backup and restore.

4.1.2. Backup and Restore

A feature that acquires and stores backup images for the purpose of backup of the Virtual Server. Disk images for backup are acquired and stored in backup storage after the backup starts. Following are disks for backup.
  • All disks for the Virtual Server
  • Image Backup does not support Virtual Machine which is over 4,000GB for total disk capacity + the memory resource (different for each Compute Class).
Backup image is overwritten on and restored from the Virtual Server from which backup is acquired.


  • The Virtual Server is restored at the state of Power Off. The Virtual Server needs to be manually started.
The restored Virtual Server is restored with the following settings for vCPU, memory, disk and vNIC.
Item Description of setting
vCPU Restores the configuration of the Virtual Server targeted for backup.
Memory Restores the configuration of the Virtual Server targeted for backup.
Disk Restores the configuration of the Virtual Server targeted for backup.
vNIC Restores the vNIC information of the Virtual Server targeted for backup (IP address, net mask, Mac address).


  • For various settings of Guest OS, settings of the Virtual Server targeted for backup are restored, but some setting items including default GW, subnet mask and DNS are not backed up. For details, refer to “Guest OS Customization”.
  • The “change S-ID” (Sysprep) that is normally performed while using Windows is not performed.

4.1.3. Backup and Restore Management

A feature for referencing the schedule and job history relevant to backup and restore and a feature for managing backup image are provided. Job indicates processing related to backup and restore. When the image backup job is completed, the result is automatically reported via E-mail.
Schedule Management Function
This is a feature that manages backup job. It is possible to create the backup job by specifying the schedule type, retention period and start date, or change or delete the created backup job.
Name Description
Effective flag (Schedule) It is possible to enable or disable this backup job.
Job history (Scheduled jobs) It is possible to select the job from the schedule configured in the past or configure a new schedule. If the job is selected from the schedule configured in the past, the configured contents are adopted.
Schedule type It is possible to select the spot (One-Time), daily, weekly and monthly backup time.
Retention period You can decide the retention period for the acquired backup image. Retention period varies depending on schedule type.
Date You can specify the date from when backup starts. For spot, daily and monthly backup, the start date can be configured. For the weekly backup, the starting day of week can be configured. For the monthly backup, the third Monday can be configured.
Time slot 24 hours can be specified in units of 1 hour.
Backup time Either image backup or file backup can be selected.


  • While the effective flag is disabled, backup does not start.
  • Time slot is the estimate of the time when backup starts so that time is not guaranteed.
The backup job can be created in units of Virtual Server and it is possible to create one backup job after combining multiple Virtual Servers.
Backup Schedule
With the schedule management function, retention time, date and time slot can be specified for each schedule type. For backup, only the method that starts the backup at the specified time slot is available. Time can be specified at the local time when backup is acquired.
  • Setting the retention period, date and time slot for each schedule type
*1 If the combination between ordinal numbers and day of week is not correct, backup does not start.
*2 Specification of date and time slot is dependent on the preconfigured time zone.

Virtual Server Management Function
For the registered Virtual Server, it is possible to check the configuration to confirm whether the backup job is enabled.
Displaying the History of Backup and Restore
History of execution of backup and restoration is displayed. History is displayed in order of time when job starts, job type (backup or restore), status (Success/Failed), execution time and target Virtual Server. Following 2 display methods: history display for the latest 7 days and all history display.
Backup Image Management and Restore
List of backup image is displayed. The list displays start time, end time, image size and disk type (all disks). Restore can be executed from the list. Restore is immediately executed. It is also possible to delete the backup image immediately.

4.1.4. Important Points

  • A Backup or Restore is failed by use conditions of the foundation. A notice mail is sent in this case, so please try re execution of Backup or Restore.
  • Backup Images are not deleted automatically even if the Virtual Server was deleted. Accounting will be continued until retention time ends in this case, so please be careful. And if the Virtual Server is deleted in the state for which backup images were still stored, it is not possible to delete the backup images by Virtual Server control panel. In this case Virtual Server can be deleted by Image Backup management panel. For details, refer to “User’s Guide (Image Backup)”.
Backup Image Store
  • Image backup supports following Guest OS license Virtua Server templates provided by NTT Communications.
Windows Server 2008 R2 Enterprise
Windows Server 2012 Standard
Windows Server 2012 R2 Standard
Red Hat Enterprise Linux Server 5.8/6.2/6.5/6.7/7.1

  • The backup image storage capacity is the size of the Disk of the Virtual Server targeted for backup. It is different from the data capacity written into the backup storage.


  • When Virtual Server is deployed from Virtual Server template backup jobs cannot be set immediately. From a first access to Image Backup setting display, please wait for about from 2 to 5 hours and set.
  • The Virtual Server is charged according to disk size.
  • The starting point of the retention period for backup storage is the start time of the backup. Charging starts from that point. No fee is charged if backup fails.
  • Snapshot volume is needed for backup storing process in Compute Resource Pool. The size is about 20 percet of “all disks and memory” assigned to Virtual Server.
  • Maximum data size for backup is up to 2032GB. If disk size is over 2032GB, back up job will be failed.
  • The Backup Image acquisition process is performed independently of whether the Virtual Server targeted for backup is powered on or off.
  • During backups, the performance of the Disk I/O of the Virtual Server that is being backed up might be reduced.
  • The backup begins within the Time Window you specify. The backup start time cannot be specified in units of minutes and seconds.
  • Backup cannot be configured in the last 5 minutes (55 minutes to 0 minute) of the 1-hour time slot for backup. (The alert message appears.)
  • If the number of backup jobs that are performed at the same time in each time slot exceeds the maximum value, we recommend using the closest available time slot within the same day or the closest date in the same time slot.
  • If the Virtual Server targeted for backup has been deleted at the backup start time, the backup will not be performed.
  • Disk of the target Virtual Server cannot be extended while performing the backup process.
  • To ensure consistency of the file system during backup, we recommend setting rest points, such as turning OFF the Virtual Server, and performing the backup.


  • When Virtual Server is shut down by Customer Portal or in Guest OS, status is change to Partially Powered Off. So please push Power Off button by Customer Portal mandatory in order to complete to be powered off.
  • If the target Virtual Server is restored during the backup, inconsistency in backup data may occur so do not perform the restore operation during the backup.
  • When restoring the backup, old root/Admin passwords used when performing the backup are enabled. Be careful not to forget old passwords because you cannot log in to the Virtual Server if you do not know these old passwords.
  • Backup image is stored in the storage for backup during the retention period specified by customer and the image is deleted when the retention period expires. The retention period cannot be extended.
  • Backup image cannot be acquired while External Storage is being mounted. Please make sure to backup after the unmount. When restoring, please remount again.
  • The character type which can be used by Friendly Name of Virtual Machine and vApp is limited to designate by the following. Backup and Restore will be failed in case of all except for that. Even when a backup is successful, it can’t be restored. When using the character for vApp and Virtual Server name besides the available ASCII by once, it is not possible to restore (Because system keeps the history all the while). So please pay attention to available character rule when assigning vApp and Virtul Server friendly name.
ASCII Charactors Example
Uppercase and lowercase of Alphabet A-Z,a-z
Number 0-9

Backup Image Restore
  • For restore, backup image is overwritten on and restored from the Virtual Server from which backup is acquired.


  • It may take some time for Guest OS Customization at the initial start-up after the restore. Please start the operation after 30 minutes, once you have confirmed the status as “Successful” on the Backup Report for the Customer Portal or received the Restore Completion Mail (If the mail receive setting is valid) Restore operation cannot be performed if the target Virtual Server is deleted.
  • Please do not operate the Virtual Machine (such as changing SID etc.) before the initial power on when restoring. Performance and Statistic Report from the past will be deleted.
  • After a restore NIC parameter in Guest OS may be changed. It cannot affect the communication, but, please contact support desk when there is some inconvenience.
  • When disk of Virtual Server under operation is deleted after backup and the disk contract of Compute Resource is being reduced, please perform restoration after checking whether the amount of disks required for restoration is secured in Compute Resource.
  • Please execute the VM restoration one by one within same Compute Resource Pool. It is necessary to have free memory and Storage on Compute Resource Pool for overhead when backup and restoring. (The overhead is recommended to be max. 20% of the memory and same volume of the Storage assigned to the Virtual Machine.)
  • If the IP Address for Virtual Machine is assigned either on vFirewall or vLoad Balancer, please release the settings of vFirewall or vLoad balancer temporarily and restore. Please contact the Support Center via Customer Portal ticket, if the restoration does not complete.
  • Please do not assign the IP Address of the Virtual Machine used during the Backup to other Virtual Machines. Restoration will fail due to IP Address duplication.
Backup of Compute Resource (Dedicated Device)
Be careful with the following points when backing up the Virtual Server used by Compute Resource (Dedicated Device).
  • For the backup work area, 10% of the Storage Device that is used by Compute Resource (Dedicated Device) will be used.
  • During the backup, the performance of the Disk I/O of the Storage Device that is used by Compute Resource (Dedicated Device) may decrease temporarily.
  • Backup of Compute Resource (Dedicated Device) may not be supported depending on usage of disk I/O so please contact us.
License of the Restored Virtual Server
  • If the Virtual Server targeted for backup was using the OS license provided by NTT Communications, the overwritten restored license on the Virtual Server is equivalent to the OS license. Therefore, no OS license is added to the restored Virtual Server.
Guest OS Setting
When changing the Guest OS network settings, do not disable a vNIC that has been recognized, even if you are not using that vNIC. If Virtual Servers with disabled vNIC are backed up and restored, failures might occur.
Difference between the Setting Time and Chargeable Duration due to Difference of Time Zone
Configurable date and time slot are set on the Portal window according to the local time (configured time zone). However, the system operated with the universal time coordinated (UTC) so that charging is processed with UTC. For Japan, backup process that takes a maximum of 9 hours is charged as the process for the previous day.
Example) Charging when backup is performed at the end of month in the Japanese time zone
To make the explanation easy to understand, Japan Standard Time (JST) is set for time zone, backup date is set to 0:00 on April 1 (Japan Standard Time) and 0 minute is set for the backup period.
If the backup retention period is set to one day, the data retention period is set from 0:00 to 23:59 on April 1 in Japan Standard Time. However, if the period is converted with UTC, the period is converted to (1) 15:00 to 23:59 on March 31 and (2) 00:00 to 14:59 on April 1. Therefore, (1) is processed as the fee for March and (2) is processed as the fee for April. The time notation in the E-mail about the result of job is UTC.
When Using OS Management
If the OS management service is used, you cannot use the image backup service.
About charging
Start point of charging is the start time of charging. This time cannot be specified in units of minutes and seconds, and this time starts in the time slot specified by the customer. Charging unit is an hour so that minutes and seconds are rounded up. Therefore, the additional one hour from the specified storage period may be charged depending on type of schedule and charging state time.