Huawei cloud computing ie interview notes – Introduction to the functions of Huawei cloud migration tool rainbow. What virtualization platforms and operating systems are supported for migration? What business migration methods are supported? What checks should be made for the OS before windows online migration and Linux online migration?


1. Function introduction: Rainbow migration tool is a migration tool developed by Huawei based on the operating system level. It provides the function of migrating the host (x86 architecture server) system and data or business systems of other virtualization platforms to the virtual machine of Huawei fusionsphere virtualization platform (fusioncompute, fusioncloud, fusioncube) completely and online without interruption.

2. Supported virtualization platforms: VMware, Xen, KVM and hyper-v.

Supported operating systems: Windows Server, SUSE, Ubuntu, RedHat, CentOS.

3. Supported business migration methods: Windows online file level migration, windows online block level migration, Linux online file level migration and Linux online block level migration. Mainly online

Windows online migration process:

① Configure cloud platform information;

② Create tasks (including filling in source host information, destination VM information, migration method, etc.);

③ Perform migration;

④ Data synchronization. Switching service

4. For the source side of windows: the firewall and anti-virus software need to be closed and installed Net framework, install the hconvertor agent, check the empty file and obtain the administrator permission

For the Linux source side: you need to turn off the firewall, turn on the SSH service, check the empty file, and obtain the root permission.


An empty file is a junk file.


Windows scenes will have snapshots. There will be no snapshot in the Linux scene. Use tar or DD.

*How many snapshots are there in the migration process? What is the purpose of each snapshot?

There are 3 snapshots for each migration and data synchronization.

1. On the source side, the NTFS of windows snapshots the system (Linux snap windows VSS) to freeze the data.

2. At the destination end, the FC takes a snapshot of the VM and takes a snapshot before configuring the system. The purpose is to prevent problems in the configuration system and roll back.

3. At the destination, the FC takes a snapshot of the VM. After configuring the system, the user VNC takes a snapshot before logging in to the test system. The purpose is to roll back and clear the test data after the test.

*What software does rainbow have? What are Huawei’s self-developed tools for business migration?

Hconvertor online migration tool

Ovfconvertor offline migration tool


Rainbow hConvertor

Rainbow ovfconvertor: offline image conversion

At present, Huawei has long stopped updating ovfconvertor and only provides online migration hconvertor tools. In the exam, most of the candidates mentioned in rainbow refer to hconvertor

*Rainbow migration process (tested)

Version 1:

1. Deploy the rainbow server, issue 80, 8443 and open the shared ports 137, 138, 139 and 445 on the server side, as well as the user-defined ports (for example, if 80 forwards 8445, issue 8445).

2. Import the license.

3. Connect to the cloud platform and configure the destination environment and shared directory (shared directory cannot be created) (connection purpose: automatically create VM. IP starts automatically).

4. Connect to the source end. If windows issues 8899 port and installs hcconverter agent (after installation, it monitors 8899 by default), there are 137-139445 (when 8899 is not turned on, install the agent directly through 445. If 445 is disabled, copy the agent installation package directly to the source end for installation); If it is Linux, port 22 is for SSH (the default port can be modified).

5. Create the destination virtual machine, start the virtual machine and mount the livecd shared by rainbow ISO file, and configure the CD-ROM drive to start, and configure the temporary IP address

6. System migration: test whether the system is available (technology used for system migration: Tar archiving + SSH delivery)

7. N incremental migrations (n > = 0)

8. Stop source side business

9. Offline migration

10. Offline synchronization

Last offline synchronization

11. Disable the source host network card

12. Change to hard disk startup

13. Start the destination virtual machine and detect

14. If it is V2V, uninstall the old tools

15. Install fusioncompute tools

16. Destination IP

17. Online business

Version 2:

1. Install the migration tool

2. Create target VM (with description as rainbow)

Configure disk, network card, CPU memory

3. Configure cloud platform, share and license

4. Configure source VM

User name, password, disk detection, partition

5. Create migration task

Configure the temporary IP of the target VM,

6. Perform migration tasks

1. Mount the agent to the source

2. Configure target IP

3. Partition the target VM

4. System migration

5. Modify the target VM

6. Migration successful

7. Test and verification: verify that the migrated system can work normally

Incremental synchronization: synchronize the newly added data after the migration of the source host to the destination virtual machine

Service switching: switch the service to the destination virtual machine after the last data synchronization

When raindow migrates online, the business will be interrupted. The interruption time is the total time of the last data synchronization and business switching

Limitations and constraints of rainbow migration? What operating systems can be migrated? What are the virtualization platforms that can be migrated?

Restrictions and constraints include: virtualization platform / server restrictions and operating system restrictions. See the following table for details:






*Can rainbow migrate apps? Lightweight database

Intention: can applications in the source OS be migrated? Application level migration?

Rhetorical question: is the migration you are referring to an application level business? If yes, you cannot migrate.

Rainbow is a system level migration tool. It cannot migrate application level services for specific applications. However, after system level services are migrated, the source applications will be migrated together, but it cannot guarantee that the applications will be available.

**Can the database be migrated? Why? Can rainbow migrate the database business? (tested)

Version 1:

1. First, make a specific analysis. The first premise is that after communicating with customers, migration is not recommended.

2. As for the migration of databases, Huawei officials have indicated that the consistency of databases and the success rate of migration are not guaranteed after the migration of operating systems. In this case, I suggest adopting the data migration scheme of database manufacturers.

3. If it is necessary to migrate, I will suggest shutdown for migration.

4. Huawei rainbow does not support block writing, file system writing and cluster writing unique to some database systems.


Version 2:

may not. The reason is that rainbow only supports system level migration, and the migration database business cannot ensure data consistency. It is recommended to adopt the business migration scheme of the database application itself, such as DataGuard or RMAN of Oracle

*How can rainbow migration reduce business interruption time?

1. First, from the perspective of service interruption duration, it is mainly divided into two parts: the last synchronization duration and service switching duration.

2. Reducing the last synchronization time is to reduce the amount of data difference. There are two ways to reduce the amount of difference:

1) When the business is idle, that is, when the amount of IO per unit time is relatively small;

2) Multiple online synchronization to reduce the difference as much as possible,

3. Reduce the service switching time, which can increase the proficiency of service migration operation in service switching, so as to shorten the service interruption time.

*Why should migrating VMS with rainbow operate when the business is idle?

When the IO is relatively large, more incremental data will be generated per unit time, which will result in a large amount of data difference in the last synchronization, and then increase the last synchronization time;

*How to determine when the last synchronization will take place in rainbow? (tested)

Whether the current time point allows the migrated business to be shut down, and whether the last interruption time is long enough for the last synchronization.

*What is the sequence principle of rainbow business migration? Business migration sequence design




*Differences between migrating to FC and fusioncloud platforms

1. Cloud platforms are configured in different ways: FC needs to add a cloud platform and fill in VRM address, user password and other information, while fusioncloud does not

2. Different ways to obtain the temporary system image: FC needs to configure the shared directory to share the winpe / livecd image. Fuisioncloud cannot configure the shared directory. It needs to download the image manually and register the image in fuisoncloud.

3. The target virtual machine is created in different ways: one is created on FC, and the other is created on SC or FM.

Four migration principles? What are the scenarios for file level migration and block level migration?










Application scenario:

Applicable scenario for file level migration: the planned target VM disk space is expanded or reduced relative to the source. Only some data files are migrated, excluding some files that are not migrated.

Applicable scenarios for block level migration:

A host that contains a large number of small files.

Hosts with high disk utilization.

The partition structure needs to be consistent with the source end. 

1. For example, the partition size of the source hard disk is 200g and the actual file size is 10g. It is recommended to use file level migration. 

2. For example, the partition size of the source hard disk is 200g, and about 150g is used. It is recommended to use block level. 

3. When migrating 32bit windows, it is recommended to use windows file level migration. 

4. If the average file size of the source side is very small and the average size is less than 100k, it is recommended to use block level. 

5. If the disk size of the source side is 100g, only 10g is actually used. When the destination side needs to be set to 150g (capacity expansion) or 15g (capacity reduction) after migration, the file level needs to be used.

Choice of rainbow migration mode

Windows recommends block level and Linux recommends file level

A large number of small files adopt block migration

Low space utilization, file level

In fact, we usually only consider “windows recommends block level and Linux recommends file level”. Because the block level migration of windows works with the NTFS file system, unused space will not be copied and data compression will be performed. Therefore, the migration speed will not be too slow due to the existence of a large amount of unused space, and it will cooperate with VSS shadow copy without causing data damage; Linux only uses the file level, because its block level will migrate unused space, and it is carried out in the case of unfixed data, which may cause data damage. When tar + Rsync is used in the file level and the files in the Linux system are not huge, the migration speed is ideal.

During the examination, use the above answers first. If the examiner questions, lead to the extended part for further explanation.


Which dimensions does rainbow support? What happens if the migration fails? What are the reasons for the failure? Who detected the failure of the network transmitting data at the source and destination? Which faults on the destination end will lead to failure? What factors affect the efficiency of migration?




If the migration fails, the web interface will report an error, which has no impact on the source production system; The reason for the failure is that the active end host or virtual machine fails, the source end target network is not connected, and the performance of the target host is insufficient; The target end checks the network fault through ICMP and reports it to the rainbow server; The performance of the destination host is insufficient, the destination network fails, the destination virtualization platform Java fails, and the destination cannot access the ISO share provided by rainbow;




What does rainbow migration check on the source host?

Rainbow migration checks the operating system version, operating system environment (whether. Net is installed, whether SSH and Rsync are available), firewall and anti-virus software on the source side.

What is the difference between virtual machine migration and rainbow migration?

Virtual machine hot migration is the migration within fusioncompute platform. Rainbow migration is mainly to migrate physical machines or virtual machines from other manufacturers to Huawei fusioncompute platform (Rainbow migration can also migrate low version fusioncompute virtual machines to high version fusioncompute platform)

What are the requirements for data storage in rainbow migration?

Rainbow migration has no requirements for data storage, regardless of whether the source and destination are virtualized or support snapshots. The reason is that rainbow migration adopts system level migration.

Rainbow’s requirements for data storage?

No requirements. (the target end of windows block requires virtualized data storage)

The virtualization platform where the source VM is located snaps the guest OS in the virtual machine (host OS physical operating system guest OS virtual operating system)

Can block level migration expand or reduce the capacity of the destination?

Windows system block migration can be expanded but not reduced; Linux block migration cannot increase or decrease capacity

Must the partition structure of the destination end and the source end of the block level be consistent?

The partition structure of windows block migration can be adjusted; The partition structure of Linux block migration is not adjustable.

What is rainbow? What are the characteristics of rainbow? What level of migration is rainbow?

Rainbow is an industry-leading business migration tool developed by Huawei, including server information collection, virtualization evaluation and capacity planning tool rainbow hsizing; Business Migration Tool rainbow hconvertor. It can provide end-to-end fusionsphere service migration. The scenarios cover P2V (physical to virtual), V2V (virtual to virtual) and virtual machine service migration within Huawei cloud platform.

Rainbow is a system level migration




How to determine what went wrong during rainbow migration?

There is a portal interface in rainbow

Log in to the portal interface. When a failure occurs, there is a step that will tell us where the failure occurred

Why did the creation of the target virtual machine fail?

Rainbow to target host network unreachable

The target virtual machine creation failed due to insufficient target host resources

What should customers pay attention to when they have business to migrate?

1. Is the business suitable for migration to cloud platform

2. Is the virtualization platform or physical host on the migration source side in rainbow’s compatibility list

3. Is the migrated source operating system in rainbow’s compatibility list

4. Length of time allowed for business interruption

Rainbow and ebackup, for data, are permanently incremental?


Who installs the agent for the source host?

Rainbow server is installed through remote login to the source host (SSH).

If there is an OA (office management system) system that needs to be migrated, what is the migration process? Can rainbow only migrate OA but not database?

Check whether the OA and the background database are on the same node. If so, it cannot be migrated (according to the database theory). If not, the OA system can be migrated. After migration, the database and the OA system can be used by adding an index relationship.

Does the source side need to take snapshots during migration? Who did it

Linux does not require snapshots

Windows needs to take a snapshot every time the source side synchronizes (Windows does not take a snapshot because VSS supports it)

Will rainbow migration take snapshots?

meeting. The migration server sends a command to the source host to take a snapshot of each partition. During block level migration synchronization, the changed sector is read from the snapshot according to the location of the changed sector block, and the changed sector is copied to the destination virtual machine.

What is the migration method for migrating 10t video files?

Adopt file level.

In fact, rainbow is not a good choice for this migration scenario. You should directly copy files or move the original media (possibly LUNs) to the destination.

The customer has a Windows 2000 host and is running business. How to migrate?

Cannot migrate

。 How to ensure that the IP of the target virtual machine is consistent with that of the source host? How?

Use the temporary IP before switching to the destination virtual machine. After the offline synchronization, disable the network card configuration IP of the source virtual machine and configure the destination virtual machine IP as the source IP.

。 In rainbow migration, the target VM failed to mount livecd. What is the possible reason?

Rainbow cannot reach the target VM network. The user name and password of rainbow share are incorrect. The ISO is corrupted

。 Which ports does rainbow migration need to open?




What are the ports involved in rainbow?




Examination questions:

Introduce the migration process from a business perspective

Ask the examiner whether to deliver or migrate the process

Can windows be expanded? Specify how to expand the capacity?

Windows block level migration can expand the capacity of partitions, but not reduce the capacity. You can increase or decrease the capacity of disks. Block level capacity increase means that the target VM disk size is larger than the source.

What is offline migration?

Migrate after business interruption.

*Can UNIX be migrated? Why? You mean the reason why it is not supported is because of the instruction set?

UNIX cannot be migrated because rainbow, a non x86 architecture server, cannot be migrated. The instruction sets of x86 architecture and non x86 architecture servers are different.

How to plan the migration source host (answer: you need to open the port, the examiner said what permissions you need, answer: you need administrator permissions, and the examiner asked why)

According to the information obtained from the customer survey, plan according to the migration sequence and migration principles. The corresponding port needs to be released. Administrator privileges are required to read migrated files.

The role of license?

The function of authorization is trial without license.

Can I migrate hosts in the same cluster?

I can answer, but the examiner may have misunderstood me

Comments: because there are associated synchronization messages between hosts in the cluster, they cannot be migrated together concurrently. There are no other problems


Let’s see what the examiner wants to ask. If you want to ask whether you can migrate the cluster system, the answer is No. If you want to ask how to do migration planning, answer according to the migration order and principles.

How does windows block level migration transfer data?

VSS shadow copy technology + NTFS file system

Linux block level migration principle, why not recommend using block level migration?

DD + SSH # Linux usuallyUnable to snap freeze frame data, the failure of DD command block level migration will result in data damage or damage to the Linux directory structure, with high risk. In addition, DD will copy the empty data (zero copy is not supported), and the efficiency of block level migration is low.

Aside from rainbow system level migration, what kind of migration is there?

File level, application level, and then briefly introduce the scenario

Will windows block migration migrate duplicate data?

I answered that NTFS will not migrate the same data without data. In addition, I also asked about the migration process of windows block migration

Comments: I don’t know enough about windows block migration. You can go back and look at the documents (here the examiner explained why duplicate data won’t be migrated, but I forgot ha ha ha ha ha ha)


Windows block migration does not migrate duplicate data,

What are the technologies used for block migration and file level?

I answered that tar + SSH is available at the Linux file level, and VSS is available at the windows block level with NTFS. He asked if there is any more? I didn’t answer. The comment said rysnc and FastCopy

Win # file level # VSS + CIFS + FastCopy

Block level VSS + NTFS

Linux # file level # tar + SSH + Rsync

Block level {DD + SSH

*Is the destination virtual machine of rainbow migration process created automatically or manually?

Manual fusioncloud and fusioncompute are both manual

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