Accessing OES Through Native Linux Methods | Novell Open Enterprise Server Administrators Handbook, SUSE LINUX Edition

In addition to accessing files through the OES NCP Server, clients can easily access the OES Linux filesystem through several native Linux methods. The two most common options for remote file access are the Network File System and Samba.

Network File System (NFS)

The Network File System (NFS) was originally created to provide for seamless disk access across a network. Through the use of an NFS server, local disk contents are exported to NFS client machines. NFS clients then access the NFS directories as though they were physically on the local disk.

SLES includes both client and server components of NFS. Although providing NFS access to the local disks is not required when using the NCP Server, it is sometimes useful or necessary to provide NFS access to clients. The following section will briefly describe the server configuration and client access methods required by NFS.

CONFIGURING NFS ACCESS

Configuring NFS file access on SLES is performed using the YaST management utility. YaST is discussed in detail in Chapter 6, "SUSE Linux Enterprise Server Management." To configure NFS, the "NFS Server" module within YaST's Networking Services section must be used.

The NFS Server module first prompts for enabling or disabling the server. If the server is enabled, the next screen allows for configuration of local directories for NFS export. To export a directory properly, the following components must be filled out:

Directory Absolute path of a local directory must be entered for proper functioning on the NFS server.
Hosts Wildcard Representation of clients that are allowed to connect to the current exported directory. A valid hosts list can consist of a set of asterisks (*) to indicate all clients or a specific IP address to represent a single client. Ranges of IP addresses and DNS names are also valid entries.
Options The options list of an NFS export is used to configure the permissions of that export. Common options include ro for read-only access, root_squash for disabling root access to the export, and sync for enabling synchronize file access.

NOTE

For more information on host wildcards and export options, see man 5 exports.

Upon completing the NFS Server configuration module, the NFS server is started automatically and clients can begin accessing NFS exports.

MOUNTING AN NFS EXPORTED DIRECTORY

When a SLES directory has been exported for NFS clients, it is imported into a remote filesystem for access. Linux systems use the mount command to accomplish this. To mount an exported directory on a Linux system, complete the following steps:

1.	Use the `mkdir` command to create a directory that will hold the OES Linux NFS export, for example: `mkdir /OESFiles`.
2.	Use the `mount` command to link the new directory to the OES Linux export, for example: `mount <server identifier>:/data/linux /OESFiles`.

WARNING

The server identifier is the IP address or DNS name of the OES Linux server on which you created the NFS Export. Make sure to use both the colon and forward slash between the server identifier and the path. The mount target directory must be an absolute path from the root and is separated from the source path by a space.

For more information on the Linux mount command, refer to your system's man pages.

Samba

Samba is a suite of programs that were created to improve interoperability between Windows and Unix-based operating systems. One major goal of Samba was to provide file and print services to Windows workstations as though the Samba server were another Windows server.

SLES includes both client and server components of Samba. Although providing Samba access to clients is purely optional, and may be alleviated by using the NCP Server, it is an extremely common requirement for Linux installations. One major problem with Samba installations is the complication of Samba normally storing valid users outside of the local Linux account structure. This essentially produces an environment where users have separate usernames and passwords just for accessing Samba resources. OES Linux resolves this problem through the use of the Linux User Management Component.

Linux User Management (LUM) acts as a middle layer between Samba and Samba users. Rather than relying on Samba-specific user accounts, LUM allows eDirectory to be used as an LDAP directory of Samba users. The configuration behind LUM is discussed in detail in Chapter 8. Configuring Samba services for users is then discussed in detail in Chapter 12.

Given the goal of Samba acting as another Windows server, configuration changes to a Windows workstation are not required. It may be desirable to configure a Windows workstation to join a specific Samba domain, but this is optional and not necessary for basic Samba implementations.

NOTE

Samba is a very complex suite of programs. For advanced configuration, including replacing Windows domains, please see the official Samba documentation at http://www.samba.org.

After enabling Samba on the SLES server, you can do file access testing using the Windows-based networking utilities or via a DOS shell. To map a drive to a Samba share from a DOS shell, use the following command:

 C:\> net use f: \\<SLES_DNS_OR_IP_ADDRESS>\<SAMBA_SHARE>

To access Samba printers, the normal Windows printer configuration utilities can be used to configure a network printer, or the local printer port can be captured to a Samba printer using the following command:

 C:\> net use lpt1: \\<SLES_DNS_OR_IP_ADDRESS>\<PRINTER>

In a Linux workstation environment, NFS is normally preferred over Samba. However, in mixed environments, Samba is often used for all client access. The easiest way to set up access to Samba resources from a SUSE Linux workstation is through using YaST. To access a Samba share through YaST, complete the following steps:

Launch the Samba Client module under YaST | Network Services.

Enter the name of the Windows Domain or Workgroup you want to join. Click Finish to complete the client configuration.

Use Konqueror to browse the entire network, or access a specific Samba share using the following URL format:

 smb://<SLES_DNS_OR_IP_ADDRESS>/<SHARE>

Samba resources can also be accessed directly from a Linux shell. The smbclient and smbmount utilities are normally used for this. The smbclient utility is used to browse Samba services on a Samba server, and the smbmount utility is used to map a Samba share to a local directory (as with NFS).

NOTE

Refer to the man pages for smbclient and smbmount for more information and on accessing Samba services from a Linux workstation.