SMC migration error: Client.Snapshot.AccessFailed

Problem description

An SMC migration task fails with the "Client.Snapshot.AccessFailed" error.

Causes

During block replication, the SMC client creates snapshot devices for disk partitions on the source server to synchronize data. This error occurs when the client cannot access a created snapshot. Possible causes include:

• Windows:

  • Insufficient free space on the disk partition.

  • Third-party security or antivirus software is installed on the system.

  • The configured storage usage limit for the shadow copy is too low.

  • The Volume Shadow Copy Service is not working correctly.

• Linux

  • Insufficient free space on the disk partition.

  • The available system memory is less than 300 MB.

  • The snapshot device for the disk partition is not working correctly.

Solutions

Follow the solution for your source server's operating system.

• Windows

  Open Event Viewer, check for errors from sources related to vss, volsnap, or disk, and resolve them based on the error messages.

  • If an error message indicates that the disk space is insufficient or a VSS shadow copy cannot grow:

    • Ensure the disk partition has sufficient free space. We recommend reserving at least 10% to 15% of the total disk space.

    • Check the configured storage usage limit for the shadow copy. If it is too low, increase the limit or select no limit, and then retry the operation.

      In the disk Properties dialog box, select the Shadow Copies tab, click Settings, and then adjust the value in the Maximum size area.

  • If you receive an "Access denied" error with the error code 0x80070005, check whether third-party security or antivirus software is installed. If such software is found, grant disk backup permissions or disable the software, and then retry the operation.

  • Ensure the Volume Shadow Copy Service is working correctly.

• Linux

  Check whether the /dev/smcss9 device exists. Run the dmesg | grep smcss command to check for errors.

  1. Ensure the available system memory is at least 300 MB.

  2. Ensure the disk partition has sufficient free space. We recommend reserving at least 10% to 15% of the total disk space.

  3. In the SMC client installation directory, run the ./Check/client_check --ssclear smcss command to clear residual snapshot devices, and then retry the migration task. For information about how to find the SMC client installation directory, see View the SMC client.

After you resolve the network issue, run the SMC client to retry the migration. For more information, see Run the SMC client.

If the issue persists, collect the logs from the /smc/go2aliyun_client*/Logs directory and contact us.