Back up for NDS
Articles and Tips:
01 Aug 1998
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Recently, a user asked me how he could recover the SYS volume of an intraNetWare server, which suffered a hard drive failure. This question brings up an interesting point: Many companies don't create backups because these companies don't want to spend the money necessary to purchase a good backup system or because they don't want to spend the time necessary to perform the backup process. Big mistake: Not only can regular backups save your company's network from certain disaster, but they can also give you the peace of mind that comes from knowing you can easily restore a server if it fails.
An intraNetWare or NetWare 4 server contains two components that you must back up: NDS and the NetWare file system. Because these components perform different functions, each component has a unique set of backup requirements that you must follow to ensure that you can fully restore the components in the event of a server failure.
This article is the first article in a two-part series that explains how to perform the backup and restore processes on an intraNetWare or NetWare 4 server. This article focuses on backing up Novell Directory Services (NDS). (A future issue ofNetWare Connectionwill include the next article in the series, which focuses on backing up the NetWare file system.)
Backup requirements vary depending on the network configuration. This article addresses backup issues for companies with one intraNetWare or NetWare 4 server and one NDS tree. This network configuration is common in small- to medium-sized companies. These companies are usually the ones most in need of a comprehensive backup plan because they don't have a large IS staff or outside consultants to develop, maintain, and test the backup plan.
If your company has only one intraNetWare or NetWare 4 server, you should be aware that Novell recommends you create a replica of every partition in the NDS tree. Ideally, you should have at least one additional server on which to store the replica. Unfortunately, most small- to medium- sized companies cannot justify installing and maintaining a second server. As a result, this article is based on the assumption that you will have to restore NDS information to the server if it fails.
WHAT YOU NEED FOR A BACK UP
Before you can perform the backup process, you need to ensure that you have the following:
Backup hardware and software
A well-functioning NDS tree
A documented backup plan
Install Backup Hardware and Software
First, you need a tape drive and backup software that have been tested and certified by Novell to work with intraNetWare or NetWare 4, as well as with Novell's Storage Management Services (SMS). SMS is an open architecture that defines how storage management products, such as Novell's SBACKUP utility and third-party backup software, access and store information on intraNetWare and NetWare 4 servers for backup and restore purposes. You can find out more about SMS by reading the following articles:
"Storage Management Services,"NetWare Connection, Sept. 1996, pp. 6-22. You can download this article from http://www.novell.com/nwc/sep.96/sms96.
"Backing Up and Restoring NetWare Directory Services in NetWare 4,"Novell Application Notes, Aug. 1995, p. 1-49. You can download an updated version of this article entitled "Overview of SMS and NDS" from http://developer.novell.com/research/appnotes/1995/august/01/02.htm.
To determine whether a particular tape drive is Novell certified, you can visit Novell's DeveloperNet World-Wide Web site to view a list of tape drives that have earned Novell's Yes, Tested and Approved certification (http://developer.novell.com/infosys/10115.htm). You can also view a list of backup software that has earned this certification (http://developer.novell.com/infosys/1000.htm).
When deciding which tape drive to purchase, you should ensure that you choose a tape drive that meets your company's storage needs. For example, suppose your company's server had 2 GB of hard drive space and your company's workstations had another 2 GB of hard drive space. If you planned to increase the server's hard drive space to 4 GB within the next two years, you would need a tape drive that provides at least 8 GB of storage capacity. (For more information about storage devices, such as tape drives, see "Storage Space: Will Bigger and Faster Mass Storage Solutions Be Enough?",NetWare Connection, Nov. 1997, pp. 6-21. You can download this article from http://www.novell.com/nwc/nov.97/massn7.)
Check the NDS Tree
Second, you must ensure that the NDS tree is functioning properly. You do not want to back up NDS if the NDS database contains errors, since you may have to rely on this backup as the only means of recovery after a server failure.
To check the status of the NDS database, you can perform an NDS health check by running the DSTRACE option at the server console. To find out what the DSTRACE option can do, you can read document numbers 2909019 and 2909026 on Novell's Support Connection web site (http://support.novell.com).
If the DSTRACE option reports any errors, you can use the DSREPAIR utility to fix these errors. To find out how to fix errors, you can read document numbers 2913292 and 2916107 on Novell's Support Connection web site. You can also read the following articles:
"The Doctor Is In: Performing an NDS Health Check,"NetWare Connection, Dec. 1997/Jan. 1998, pp. 33-41. You can download this article from http://www.novell.com/nwc/dec.97-jan.98/ndshcd7.
"Troubleshooting Tips for NetWare Directory Services,"Novell Application Notes, Aug. 1995, pp. 69-77. You can download an updated version of this article from http://developer.novell.com/research/appnotes/1995/august/a3frame.htm.
Make a Backup Plan
Third, you need a documented backup plan. To help you create a backup plan, you can refer to Novell's backup guidelines for intraNetWare and NetWare 4. (For an outline of these guidelines, see "Backing Up and Restoring Novell Directory Services in NetWare 4.11,"Novell Application Notes, Oct. 1996, p. 42. You can download this article from http://developer.novell.com/research/appnotes/1996/october/a3frame.htm.)
The backup plan should include the names and telephone numbers of the network administrators in your company who are responsible for ensuring that the backup process runs. In addition, the backup plan should include a list of the critical information stored on each server in the NDS tree. For example, you would list the following information:
The server's name
The server's internal IPX address
The NetWare license numbers and user configurations installed on the server and the order in which they are installed
The names and sizes of the mounted volumes on the server
The names and version numbers of the LAN and disk drivers installed on the server
The IPX and IP addresses of the network interface boards installed in the server
The NDS partition and replica information stored on the server
The backup plan should also include a schedule for performing the backup process. Novell recommends that you back up the entire NDS database immediately before and immediately after making significant changes to this database, such as creating, modifying, or deleting NDS objects. In addition, Novell recommends that you back up the entire NDS database at the same time that you back up the NetWare file system.
Finally, the backup plan should include a schedule for rotating backup tapes. This schedule can consist of something as simple as using a separate tape for each day of the week or as complex as using a managed schedule, such as the Tower of Hanoi system. (You can find an excellent description of this system at http://www.cut-the-knot.com/recurrence/hanoi.html.)
Managed schedules are usually implemented as scripts that come with the backup software you are using. This backup software may also include information about how to use each schedule and about the number of backup tapes needed for each schedule.
In addition to making a backup plan, you should copy the STARTUP.NCF file and the AUTOEXEC.NCF file from the server onto a floppy diskette. (You should use a separate floppy diskette for each server's files.) You should then store the floppy diskette, along with a working copy of the NetWare license diskettes and the NetWare documentation.
If the server uses additional .NCF files during the startup process (the UNISTART.NCF file, for example), you should also copy these files onto the floppy diskette.
HOW YOU CAN PERFORM THE BACKUP PROCESS
Before you begin the backup process, you must load the target service agent (TSA) that allows you to back up NDS. Novell makes each NetWare service, such as NDS, available to SMS-compliant backup software via a corresponding TSA.
To back up NDS, you load Novell's TSANDS NetWare Loadable Module (NLM) at the server console. The most recent TSANDS NLM, which is dated March 11, 1998, is included in the latest version of intraNetWare Support Pack. (As we go to press, the latest version is intraNetWare Support Pack 5.0, which you can download from http://support.novell.com/misc/patlst.htm.)
You must also load the NLM for the backup software you have installed. For example, if you were using Novell's SBACKUP utility, you would load the SBACKUP NLM at the server console. (You can download the most recent SBACKUP NLM, which is dated June 26, 1996, from http://support.novell.com/misc/patlst.htm.)
At this point, you can start the backup process. This section gives you an idea of the steps you must follow, but the exact steps vary, depending on the backup software you are using. As mentioned earlier, these steps are designed for companies with one intraNetWare or NetWare 4 server and one NDS tree.
After you load the backup NLM, you select the option from the main menu that enables you to start the backup process. The backup software should then display a list of available NetWare services that you can back up via SMS. In this list, you should see an option for NDS, which may appear as Novell Directory or as the name of your company's NDS tree. You select this option, ensuring that you choose to back up NDS at the [Root] object.
Next, the backup software should prompt you to enter a username and password, which allows the backup software to access the server. You must enter a username that has ADMIN or ADMIN-equivalent rights to the [Root] object. Otherwise, the backup software cannot back up the entire NDS database.
Depending on the backup software you are using, you may have the option of scheduling a time for the backup process to start. You may also be able to specify whether you want this process to automatically occur on a regular basis based on the date, the day of the week, or the time of the day.
After you have completed the necessary steps, the backup software performs the backup process either immediately or based on the schedule you have specified. You are then prepared to restore NDS in the event of a server failure.
HOW TO PERFORM THE RESTORE PROCESS
Before you restore NDS, you need to repair whatever hardware failed in the server. You then need to reinstall intraNetWare or NetWare 4, using the same server name, internal IPX address, and volume structure as you were using prior to the server failure. If you do not accurately recreate the exact server environment, you may lose both NDS information and NetWare file system information that is critical to the operation of the server.
Next, you install all of the latest NetWare patches and updates to ensure a clean restore. You then install the backup software you are using, along with any patches and updates available for this software. At this point, you load the following:
The necessary drivers for the tape drive.
The TSANDS NLM and the TSA410 NLM. (The TSA410 NLM allows you to back up the NetWare file system. The next article in this series will discuss the TSA410 NLM.)
The backup software NLM.
After you load the backup software NLM, you select the option from the main menu that enables you to start the restore process. Depending on the backup software you are using, you may then need to perform an extra task: Because the server failed, the backup software's catalog of previous backup sessions may be unavailable. As a result, you may need to perform a manual catalog operation, which is often called asession recovery. In a session recovery, the backup software reads the session information that is stored on the backup tape and uses this information to build a new catalog on the server's hard drive.
Once the catalog is available, you select the latest backup session to restore from, and you enter a username and password. Again, you must enter a username with ADMIN or ADMIN-equivalent rights to the [Root] object of the NDS tree, and you must ensure that you restore NDS at the [Root] object. You must also specify whether you want to start the restore process immediately or to defer this process until a later time. In most cases, you will probably want to start the restore process immediately.
At this point, the restore process should begin copying NDS information from the backup tape to the server. After this process is completed, you copy all of the .NCF files from the floppy diskette you created to the SYS:SYSTEM directory on the server. You then down the server and copy the STARTUP.NCF file from the floppy diskette to the appropriate directory on the server's boot drive, (the C:\NWSERVER directory, by default).
Next, you make the necessary changes to the STARTUP.NCF file to ensure that you load the latest NetWare patches and updates. Although you already installed these patches and updates, the version of the STARTUP.NCF file you are using may not include the proper commands to load the patches and updates. It's better to be safe than sorry!
You then reboot the server. To be on the safe side, you may want to run the DSREPAIR NLM to ensure that no errors were introduced when you restored NDS. If you do not fix any errors before you restore the NetWare file system, users' file system rights may not be properly restored. Finally, you restore the NetWare file system. (As mentioned earlier, a future issue ofNetWare Connectionwill explain how to back up and restore the NetWare file system.)
CONCLUSION
In addition to following the guidelines mentioned in this article, you should be aware of a few tips that will help you properly back up and restore NDS.
Keep a written record of all of the critical information stored on each server. This record ensures that you recreate the server environment exactly as it was before the server failure.
Always back up NDS immediately before and after making significant changes to the NDS tree. Also, regularly back up NDS as part of your company's daily backup routine.
Use the Verify function built into the backup software you use to ensure the integrity of the NDS information you are backing up.
Never consider capabilities such as Redundant Array of Independent Disks (RAID) or disk mirroring to be a replacement for backups. These capabilities are designed only to keep a server running in the event of a single device failure--not a total server failure.
Treat a server with the respect it deserves. Because the server maintains all of the data that is critical to the operation of your company, you should perform proper maintenance tasks on a regular basis to keep this server running smoothly. The more attention you give a server, the less likely you are to experience a server failure.
If you want additional information about backing up NDS, you should read the following documents:
"Backing Up and Restoring NetWare DS" (document number 2914422 on Novell's Support Connection web site at http://support.novell.com)
"Understanding, Identifying,&Resolving NDS" (document number 2936135 on Novell's Support Connection web site at http://support.novell.com)
Backing up your company's intraNetWare or NetWare 4 server is always worth the money and time necessary to purchase a good backup system and to perform the backup process. Regular backups will provide you with a significant sense of well-being about the reliability of your company's network. These backups will support you if the server hardware fails, allowing you to restore all of the information you backed up at a moment's notice.
Mickey Applebaum has worked with NetWare for more than 14 years. Mickey provides technical support on the Internet for The Forums (http://theforums.com).
NetWare Connection,August 1998, pp. 43-45
* Originally published in Novell Connection Magazine
Disclaimer
The origin of this information may be internal or external to Novell. While Novell makes all reasonable efforts to verify this information, Novell does not make explicit or implied claims to its validity.