Server Migration Center:What do I do if the "Btrfs has been removed" error message appears?

Problem description

The "Btrfs has been removed" error message appears during an operating system migration.

Cause

The source operating system uses the Btrfs file system, which Anolis and Alibaba Cloud Linux do not support. Files in partitions that use Btrfs cannot be read after migration, causing the migration to fail.

Solution

1. Connect to the Elastic Compute Service (ECS) instance whose operating system you want to migrate. For more information, see Connect to a Linux instance by using a password or key.

2. Run the following command to view the file system of each partition:

   df -T

   A command output similar to the following one is returned:

   [root@iZbp104w56ovfyfxy9o**** ~]# df -T
   Filesystem     Type     1K-blocks    Used Available Use%     Mounted on
   devtmpfs       devtmpfs   3920472       0   3920472   0%     /dev
   tmpfs          tmpfs      3931060       0   3931060   0%      /dev/shm
   tmpfs          tmpfs      3931060     532   3930528   1%      /run
   tmpfs          tmpfs      3931060       0   3931060   0%      /sys/fs/cgroup
   /dev/vda1      ext4      41152812 2562508  36686596   7%      /
   tmpfs          tmpfs       786216       0    786216   0%      /run/user/0
   /dev/vdb1      btrfs      20971520 1048576  19922944  6%      /mnt/btrfs

3. Run the following command to back up files in the Btrfs partition to a non-Btrfs partition:

   rsync -av /mnt/btrfs/ /backup

4. Run the following command to unmount the Btrfs file system:

   umount /mnt/btrfs

5. Run the following command to uninstall the Btrfs module:

   rmmod btrfs

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