Help Center/ Server Migration Service/ FAQs/ Disk Management/ How Do I Merge Disks During a Linux Migration?
Updated on 2024-02-01 GMT+08:00

How Do I Merge Disks During a Linux Migration?

Scenario

When you migrate a Linux server, you can migrate partitions from different disks on the source server to a single disk on the target server.

Solution

You can modify the SMS-Agent configuration file on the source server.

  • The modified configuration file will only be used for the target server. It will not affect the source server.
  • The migration progress bar on the SMS console may not be able to show the real-time progress after you modify the configuration file.
  1. On the source server, go to the config directory in the Agent installation directory.

    cd SMS-Agent/agent/config

  2. Open and edit the disk.cfg configuration file in config.

    vi disk.cfg

  3. Modify parameters under vol_disk_modify.

    • vol_name: Enter the names of the source partitions.
    • new_vol_name: Enter the names of the target partitions.
    • disk_name: Enter the names of disks where the source partitions are located.
    • new_disk_name: Enter the names of target disks.

    In this example, we will migrate the vdc1 partition on the vdc disk and the vdd1 partition on the vdd disk of the source server to the vdb4 and vdb5 partitions on the vdb disk of the target server.

    [vol_disk_modify]
    vol_name=/dev/vdc1;/dev/vdd1
    new_vol_name=/dev/vdb4;/dev/vdb5
    disk_name=/dev/vdc;/dev/vdd
    new_disk_name=/dev/vdb;/dev/vdb
    • Use semicolons (;) to separate disk or partition names. Make sure that the same number of values configured for each of the above four parameters.
    • Make sure the target disk is larger than the total size of all the partitions on it, or the migration may fail. If you need to resize the target disk or add a new disk, see Resizing Disks and Adding Disks.
    • Make sure that you follow the right naming format of "Disk name+Partition number", for example, vdb4. The new partition name must be unique.
    • Neither LVM nor Btrfs partitions can be merged.

  4. Save settings in the disk.cfg configuration file and restart the Agent.

    :wq

Resizing Disks

You can resize target disks by modifying the disk_size_modify parameter in the disk.cfg configuration file.

  • disk_name: Enter the names of target disks.
  • adjust_size: Enter the new disk sizes.
In the following example, we will change the size of the target disk vdb to 40 GB.
[disk_size_modify]
disk_name=/dev/vdb
adjust_size=40G
  • If the target disk is a system disk, its size range must be from 40 GB to 1024 GB.
  • If the target disk is a data disk, its size range must be from 40 GB to 32,768 GB.

Adding Disks

You can add disks by modifying the disk_add parameter in the disk.cfg configuration file.

  • disk_name: Enter the names of new disks.
  • adjust_size: Enter the sizes of new disks, in GB.
In the following example, we will add a 10 GB disk called vdd to a target server.
[disk_add]
disk_name=/dev/vdd
disk_size=10G
  • The disk name must comply with the naming rules and must be unique.
  • The disk size range must be from 10 GB to 32,768 GB.