Constraints

Table 1 lists the constraints and limitations of SMS.

**Table 1** SMS limitations
Item	Description
Server specifications	Windows: Source and target servers must have more than 1 CPU and 1 GB memory. Linux: Source and target servers must have at least 1 CPU and 1 GB memory.
Source server quantity	A maximum of 1,000 source servers are allowed per account. Delete the migrated servers from the server list in a timely manner so that other servers can continue to be migrated.
OSs	Supported Windows OSs Supported Linux OSs A server running multiple OSs cannot be migrated.
Available disk space	Windows At least 320 MB available space on a partition not smaller than 600 MB At least 40 MB available space on a partition smaller than 600 MB Linux At least 200 MB of available space on the root partition
File systems	Windows: Only NTFS file systems are supported. Linux: Only Ext2, Ext3, Ext4, VFAT, XFS, and Btrfs file systems are supported.
Shared file systems	SMS cannot migrate files from shared file systems such as NFS or CIFS, or from NAS devices.
External storage of servers	SMS cannot migrate data from the external storage attached to a source server.
Encrypted files	SMS cannot migrate OSs that contain protected folders or encrypted volumes.
Servers running multi-node databases and Active Directory Domain Services (AD DS)	SMS cannot migrate servers that host active directories or multi-node databases.
Data of database applications and domain controller applications	SMS cannot migrate data of database applications and domain controller applications.
Applications bound to hardware	SMS does not support migration of OSs that contain applications bound to hardware.
Dynamic disks	Dynamic disks in Windows systems are migrated as basic disks. After the migration is complete, the target server will not have dynamic disks.
Servers added to a domain	After migrating servers added to a domain, you need to add them to the domain again.
Servers with system volumes located on disks other than the first disk	SMS cannot migrate servers whose system volumes are not on the first disk.
Thinly-provisioned volumes	SMS cannot migrate thinly-provisioned volumes.
Servers with RAID arrays	SMS cannot migrate servers with RAID arrays.
Big data clusters and container clusters	SMS cannot migrate clusters including but not limited to container clusters and big data clusters.