Dell PowerVault 725N (Rackmount NAS Appliance) - Manual (Page 151)

User Name Mapping
User Name Mapping provides mapping of names between the UNIX and Windows environments. You can configure User Name Mapping from the SFU MMC
Console or by using the NAS Manager to configure properties for the NFS Sharing Protocol. With User Name Mapping, you can create simple maps between
Windows Powered user accounts and corresponding UNIX accounts. You can also use the Advanced Map feature to map accounts with dissimilar names.
Because UNIX user names are case-sensitive, and Windows Powered operating system names are not, the use of User Name Mapping can greatly simplify
maintaining and managing accounts in the two environments. User Name Mapping uses Network Information Service (NIS) or local Personal Computer Network
File System (PCNFS) user and group files to authenticate users. Also, User Name Mapping supports bidirectional one-to-many mapping, allowing you to map a
single UNIX or Windows Powered operating system account to multiple accounts in the other environment. For example, you can map more than one
administrative account in a Windows Powered operating system to the UNIX root account.
Special Mappings
By default, the root user for the UNIX client is mapped to an unmapped user. This setting is commonly known as "root squashing." When an NFS
authentication request is made for a user name mapped to an unmapped user, the result is an anonymous UID and GID (typically -2 and -1, respectively). Any
files created by such a user will show file ownership as an anonymous Windows user.
To create user and group name maps, perform the following steps:
1. Log in to the NAS Manager.
2. From the NAS Manager, click Shares.
3. Click Sharing Protocols.
4. Click NFS Protocol, and then click Properties.
5. Click User and Group Mappings.
6. Use the User and Group Mappings window to define your user and group maps.
Configuration
To configure the type of server to be used to access UNIX user and group names, perform the following steps:
1. On the User and Group Mappings window, click General.
2. Click Use NIS server, or click Use password and group files to select the server type.
3. Depending on whether you use an NIS server or password and group files, perform one of the following steps:
l For password and group files, specify the location and filename of the UNIX password file and UNIX group file.
l For NIS server, type the NIS domain and, optionally, the name of the NIS server.
4. Click OK to apply the configuration.
Defining Maps
To define simple maps in SFU, perform the following steps:
1. In the User and Group Mappings window menu, click Simple Mappings.
2. Click Enable Simple Mapping.
3. Specify the Windows Domain.
4. Click OK to create the maps.
If you are defining explicit maps, you create user and group maps individually. To create explicit maps, perform the following steps:
1. On the User and Group Mappings window menu, click Explicit User Mapping to create user maps, or click Explicit Group Mapping to create group
NOTE: To prevent SFU from performing root squashing for specific NFS shares, the UNIX root user and group must be mapped to the Windows
administrator user and group. The "access type" for the NFS share's permissions must also be set to root for each applicable client or client group.
NOTE: The UNIX password file and group file formats must conform to the UNIX standard for these files.