Aliyun How to replace a system disk

　　Aliyun How to replace a system disk

By replacing the system disk for the instance, you can implement:

Replace the operating system

Increase system disk capacity

Attention matters

Before replacing the system disk, be sure to read the following considerations carefully

Risk

　　This operation needs to stop your instance and will therefore disrupt your business.

　　After the replacement is complete, you will need to redeploy the business running environment on the new system disk, which may cause a long interruption to your business. So please be careful.

The system retains a user snapshot after the system disk is replaced. Note, however, that replacing the system disk is equivalent to replacing your system disk, changing the disc ID, and that your original system disk user snapshot will not be available for rolling back the new system disk. A reserved user snapshot can be used to create a custom mirror.

To complete the automatic snapshot policy for the new disk to maintain a sufficient number of snapshots, you can delete unwanted snapshots.

When an instance replaces the system disk, the original system disk is released.

Description

When you replace the system disk, you can specify the new system disk capacity size, but the new capacity can only be greater than or equal to the current capacity, not less than the current capacity.

Replacing the system disk does not change the IP address and MAC address of your instance.

Cross-platform considerations

When you make a Cross-platform operating system replacement, the partition format of the data disk may not be recognized.

If your data disk does not have important data, it is recommended that you reinitialize the data disk and format it as the default partition for the appropriate system.

If you have important data for your database:

When Windows systems are switched to Linux, Linux is not recognized by default in NTFS format and requires you to install software identification separately, such as ntfs-3g.

When Linux replaces the operating system to Windows, the Windows system defaults to Ext3, Ext4, XFS, and other file system format disks that require you to install software identification separately, such as Ext2read, EXT2FSD, and so on.

Data backup

　　replacing the system disk will cause automatic snapshots and data loss of your existing system disk. Please do backup in advance .

You can manually take snapshots and back up your data. Please refer to the Create snapshot.

You can also keep automatic snapshots and prevent automatic snapshots from being released with disk. Please refer to Automatic snapshots released with disk.

If you plan to use a custom mirror as your system disk, first create a custom mirror.

To replace the system disk step

If you are sure you need to replace the system disk, follow these steps:

Creates a snapshot of the current system disk.

Creates a mirror based on the snapshot of the system disk.

Replace the system disk and, if necessary, increase the disk capacity.

Set the snapshot policy for the new system disk.

Extend the system disk.

Step 1: Create a snapshot of the current system disk

Avoid snapshot creation at the peak of your business to avoid impacting your business.

A 40GB snapshot, which takes approximately 40 minutes to create in the first time. So please set aside enough time.

Log on to the Cloud Server Management Console.

Click an instance in the left navigation. Then select the region at the top of the page.

Click the name of the instance where you want to replace the system disk.

Click this instance disk in the left navigation.

Locate the system disk and click to Create the snapshot on the right. Give a snapshot a name that is easy to remember.

Click the snapshot of this instance on the left. You can see the progress of creating snapshots.

Step 2: Create a mirror

To continue with the steps above, on this instance snapshot page, select the snapshot that you just created, and then click the create custom mirror on the right. Give a mirror a name that is easy to remember.

Return to the left navigation, click Mirroring to see the mirror you just created.

Step 3: Replace the system disk

To continue with the above steps, click the instance in the left navigation. Then select the region at the top of the page.

Stop the instance before replacing the system disk. In the list of instances, select the instance of the system disk that you want to replace, and then click Stop below.

When the instance is stopped, click on the more > Replace system disk on the right.

You will be prompted to carefully operate, please be sure to read carefully notes. Once the confirmation is correct, click OK to replace the system disk .

Select the custom mirror you just created. You can also select a public mirror, a mirror that other accounts share to you, or mirror the mirror market.

Select the operating system and set the system disk size. In this step you can increase the size of the system disk to achieve the expansion of the system disk. The currently supported system disk size range is 40GB-500GB.

Set the password for the default account (Administrator or root).

Click to pay . Costs will be incurred if the costs are incurred.

You can monitor the system state through the management console, which typically takes approximately 10 minutes to complete the replacement operating system. When finished, the instance is started automatically.

If you encounter the following error message when you replace the system disk: failed to replace the OS, please stop and then Operation , or ECS task is conflicted . This may be because the system disk is creating a snapshot. Wait until the snapshot is created to replace the system disk, or in the snapshot list, manually remove the completed snapshot and replace the system disk.

Step 4: Reset the automatic snapshot policy

You need to reset the snapshot policy for the system disk that you just replaced. Please refer to setting up an automatic snapshot policy for the disk.

Step 5: Extend the system disk (for Windows instances only)

If you select the Windows operating system and have a capacity of more than 40GB, you also need to log on to the instance to extend the system disk. Please refer to the extended system disk.