CIFS Feature

Introduction to CIFS

Server Message Block (SMB) is a protocol used for network file access and CIFS is a public version of SMB. SMB allows a local PC to access files and request services on PCs over the local area network (LAN).

Storage systems support SMB 1.0, SMB 2.0, SMB 2.1, and SMB 3.0. Storage systems are adaptive to protocol versions according to Windows OSs running on clients.

• If a client runs Windows Server 2003 or Windows XP, SMB 1.0 is used.
• If a client runs Windows Server 2008 or Windows Vista, SMB 2.0 is used.
• If a client runs Windows Server 2008 R2 or Windows 7, SMB 2.1 is used.
• If a client runs Windows Server 2012 or Windows 8, SMB 3.0 is used.

• The SMB 1.0 service is disabled by default. If a client runs Windows Server 2003 or Windows XP, you must run the change service cifs smb1_enable=yes command on the storage system to enable the SMB 1.0 service. With SMB 1.0, you are advised to use Windows clients to access CIFS shares. You can run the show service cifs command to query whether functions related to CIFS services are enabled. For details, see the command reference.
• SMB 1.0, limited by its own mechanisms, cannot ensure service continuity during online upgrade.
• For environments with existing CIFS clients running SMB 1.0, you should upgrade the clients to a later SMB version as soon as possible to prepare for security and compliance enhancements.

The CIFS feature allows Windows clients to identify and access shared resources provided by a storage system. With CIFS, clients can quickly read, write, and create files in a storage system as on local PCs.

Related Concepts

Homedir: one of CIFS share modes. Homedir shares a file system to a specific user as a private directory. Different from common CIFS shares, when accessing a Homedir share, a user accesses a private directory. Homedir shares can be created (including share permission setting and feature enabling/disabling), queried, modified, and deleted like common CIFS shares.

Homedir has the following benefits:

• Allows a customer to map Homedir directories of various users to different file system paths based on service requirements.
• Allows a user to access multiple Homedir shares using Homedir share names.
• Allows all share-related features to be enabled/disabled like common CIFS shares.
• Offers AutoCreate for mapping rules, preventing administrators from creating Homedir directories separately for each CIFS user and thereby simplifying O&M.

License Requirements

The CIFS feature requires a license.

For details about the license, see "Software Specifications" in the product description specific to your product model. To obtain a license, contact your local Huawei representative office or Huawei authorized distributor.

Compatible Products

Supported Protocol Versions

The storage system supports SMB 1.0, SMB 2.0, SMB 2.1, and SMB 3.0.

Network Requirements

The CIFS feature supports both IPv4 and IPv6 network access protocols.

Interaction with Other Features

Table 1-5 describes the relationship between the CIFS feature and other features.

System Impact

File systems can be shared in NFS, CIFS, FTP and HTTP modes at the same time. When clients concurrently access a file system using different protocols, the overall performance deteriorates slightly.

CIFS Share in a Non-Domain Environment

A storage system can employ CIFS shares to share file systems as directories to users. Users can only view or access their own shared directories.

As shown in Figure 1-6, a storage system serves as a CIFS server and employs the CIFS protocol to provide shared file system access for clients. After the clients map the shared files to the local directories, users can access the files on the server as if they are accessing local files. You can set locally authenticated user names and passwords in the storage system to determine the local authentication information that can be used for accessing the file system.

Figure 1-6 CIFS share in a non-domain environment

CIFS Share in an AD Domain Environment

With the expansion of LANs and WANs, many enterprises use AD domains to manage Windows-based networks, simplifying network management and improving network scalability.

A storage system can be added to an AD domain as a client, thereby being seamlessly integrated with the AD domain. An AD domain controller saves information about all the clients and groups in the domain. The AD domain controller authenticates clients which request access to CIFS shares provided by the storage system. AD domain users can implement file-specific permission management. Different clients have different permissions for each shared directory. A client in an AD domain can only access the shared directory with the same name as the client.

Figure 1-7 CIFS share in an AD domain environment