How to perform a backup of NDMP Filers (NAS) with the Symantec Backup Exec 11d ( and above) for Windows Servers Network Data Management Protocol (NDMP) Option.
NDMP is an acronym for Network Data Management Protocol, which is an open standard protocol for enterprise-wide backups of heterogeneous network-attached storage. NDMP is an Internet-Draft standard that uses port 10000 by default.
The Symantec Backup Exec 11d (and above) for Windows Servers NDMP Option lets Backup Exec use the Network Data Management Protocol (NDMP) to initialize and control backups and restores of Network Attached Storage (NAS) devices such as NetApp filers as explained below.
The architecture follows a client-server model and the backup software is considered to be a client to the NDMP server. For every connection between the client and the NDMP host, there is a virtual state machine on the NDMP host that is controlled using NDMP. This virtual state machine is referred to as the NDMP server.
Currently an NDMP server can be thought of providing two services:
- A DATA server - This service either reads from disk and produces an NDMP data stream (in a specified format) or reads an NDMP data stream and writes to disk, depending upon whether a backup or restore is taking place.
- A TAPE server - This service either reads an NDMP data stream and writes it to tape or reads from tape and writes an NDMP data stream, depending upon whether a backup or restore is taking place. All tape-handling functions, such as split-image issues, are dealt with by this service.
- For more details on NDMP Protocol please see the following site:
NDMP Filers (NAS):
NDMP Filers, or NAS devices, reside on the network with the primary purpose of providing file services. NAS devices that use standard operating systems (for example, Windows-powered NAS devices) support the installation of backup agents, and can therefore be backed up like any other file server. However, some NAS devices use a custom operating system that does not support third party backup agents. A standard backup interface for NAS devices exists in the form of the network data management protocol (NDMP), which is a backup standard for NAS devices that do not support installation of a backup agent.
With Symantec Backup Exec 11d ( and above) for Windows Servers, the NDMP Option lets Backup Exec use the Network Data Management Protocol (NDMP) to initialize and control backups and restores of Network Attached Storage (NAS) devices such as NetApp filers. The NDMP option supports both backing up data to a tape device directly attached to the NDMP device (direct-attached) and backing up data to a tape device attached to another NDMP device (filer-to-filer) as explained and shown in Figure 1 and 2.
NDMP - Direct Attached:
In the direct-attached or local model, the backup server uses NDMP over the LAN to instruct the filer to start the backup. The filer then sends the data contained in the backup to a tape device attached directly to the filer via Fibre Channel or SCSI. During the backup, information about files and directories written to tape is transferred via NDMP over the LAN to the backup server where it is maintained in an index. For a restore operation, the backup server uses NDMP over the LAN to instruct the filer to start restoring files. Data is read from the filer's locally attached tape device and stored by the filer. During backup and restore, the backup server does not ever receive the actual data being written or read from tape. As a result, this model is commonly referred to as "LAN-free" backup.
NDMP - Filer to Filer (3-way)
In the filer-to-filer model, often referred to as three-way, the backup server uses NDMP over the LAN to instruct filer A to start backing up data to tape devices attached to filer B via either the same network or a private backup network. During the backup, information about files and directories written to tape is transferred from filer A via NDMP over the LAN to the backup server, where it is maintained in an index.
This is known as 3-way backup, since typically 3 hosts are involved as shown. (Figure 2)
- The host running the NDMP client (1).
- The host running the NDMP DATA server (2).
- The host running the NDMP TAPE server (3).
The Symantec Backup Exec NDMP Option provides support for the following functionality:
2. Support for NDMPv4. For more on NDMPv4 please visit: http://www.ndmp.org .
3. Support for Direct-Attached (tape device on filer). (Figure 1)
4. Support for Filer-to-Filer (tape attached to a remote filer of same brand, "3 way"). (Figure 2)
5. The NDMP Option supports Backup selections from the directory level.
6. The NDMP Option supports Restore selections to the file level.
Steps to back up an NDMP Filer
2. Configuring the NDMP device.
3. Backing up using the NDMP Option.
Stage 1: Installing the NDMP Option.
The NDMP (Paid) Option is installed locally on the media server as a separate add-on component of Backup Exec for Windows Servers to protect supported NAS devices. No files are copied to the NDMP device.
To install the NDMP Option on the local media server:
The duplicating of NDMP backup sets is also not supported.
Adding an NDMP storage device:
Adding a tape device attached to an NDMP device as a Backup Exec storage device also adds the NDMP device to the backup selection list.
To add an NDMP storage device:
Note: This node displays only if you have installed a licensed version of the NDMP Agent. You cannot select this node for backup. However, you can expand the node to view and select NetApp filers for backup
For more details on the NDMP option and the NDMP restore process, please see the Symantec Backup Exec 11d for Windows Servers Administrator's Guide.
Stage 2: Configuring the NDMP device.
In order for Backup Exec to back up NDMP resources, the NDMP service must be running on the NDMP device. The NDMP Service can be started by entering the following command on the NDMP device (accessed using telnet or the web interface or local login):
NDMPFILER> ndmpd on as shown in Figure 6.
The NDMP device must be configured to use the challenge (MD5) method for authentication by using the following command:
NDMPFILER> options ndmpd.authtype challenge as shown in Figure 7.
To authenticate with the NDMP server you should use the root password or non-root user with system generated NDMP-specific password. To configure these and other settings, refer to your NAS documentation.
Note: Make sure NDMP Version on the Remote Filer is set to "Level -4". If the level is below "4" then backup is not possible, However user can view the resources but can not expand , To check the NDMP Version, type following command on the Filer.
ndmpd version as shown in Figure 8
To set the NDMP level to "4" type the following command on the Filer.
ndmpd version 4 as shown in Figure 9.
Stage 3: Backing up using the NDMP Option.
In order to use the NDMP option, a tape device must be attached to an NDMP device. The tape device can be attached directly to the NDMP device being backed up or to another NDMP device. The NDMP device being protected must be added to either NDMP Devices or User-defined Selections. The tape device attached to an NDMP device must be added to the list of Backup Exec devices.
If the users add a tape device attached to an NDMP device as a Backup Exec storage device, Backup Exec automatically adds the NDMP device to the backup selections list. If you want to protect an NDMP device that does not have a tape device attached, you can add the NDMP device just to the backup selections list.
Note: Only NDMP data can be backed up to unshared NDMP storage devices. Priot to Backup Exec 12.5, a library could not be shared between a filer and a Media Server, because the machine that accesses the library first will have ownership of it, and the other machine won't have access. Backup Exec 12.5 introduced the ability to share a library with a media server (depending on configuration possible with SSO required) thus allowing Windows server based data to use the same library as that used for NDMP data.
The NDMP device and the tape devices directly attached to it are now listed in the devices pane as shown in Figure 11 below.
To backup NDMP resources: