Microsoft KB Archive/97813

= How to Use LAN Man Fault Tolerance to Mirror Boot Drive =

Article ID: 97813

Article Last Modified on 9/30/2003

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APPLIES TO


 * Microsoft LAN Manager 2.0 Standard Edition
 * Microsoft LAN Manager 2.1 Standard Edition
 * Microsoft LAN Manager 2.1a

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This article was previously published under Q97813



SUMMARY
To protect against data loss, the Microsoft LAN Manager Fault Tolerance (FT) system allows you to monitor disk operations and correct errors. A mirrored drive consists of a master partition on one drive and a duplicate partition on another drive.

You can mirror any logical drive, including the boot volume. There are two reasons to mirror the boot drive:


 * to verify or restore data
 * to be able to start from the boot volume duplicate

Before using the instructions below, please read Chapter 14, &quot;Protecting Against Data Loss,&quot; in the Microsoft &quot;LAN Manager Administrator's Guide&quot; for version 2.1.



System Requirements
FT requires a LAN Manager 2.1 server with at least:


 * two hard disks
 * Microsoft OS/2 1.3
 * HPFS

The CONFIG.SYS file must contain the line:   IFS=HPFS386

Option 1: Mirroring to Verify or Restore Data
To do this, use the Ftsetup utility (explained in the &quot;LAN Manager Administrator's Guide,&quot; page 296). To administer and correct errors, use the Ftadmin utility. If there is a complete failure of the boot drive, see page 317 of the &quot;Administrator's Guide&quot; for instructions on how to replace or repair the boot drive and recover.

Option 2: Mirroring to Be Able to

Start from the Boot Volume Duplicate
If you want to be able to boot from the duplicate volume in the event of a complete master volume failure, you must set up FT with the following characteristics (explained in the &quot;Administrator's Guide,&quot; page 298):

The master volume must be:


 * the only volume on the disk
 * at least 2% to 5% smaller than the disk it is on

The duplicate disk must be:


 * runnable from the same type of controller as the boot partition
 * at least as large as the boot disk without partitions

If the two disks are on the same controller and there are multiple disk controllers in the system, physically disconnect the remaining controllers before mirroring. To achieve the best possible results, the FT system will mirror disks on any available controllers, so you must disconnect others to ensure that the mirror of the boot drive ends up where you want it.

Booting from the Duplicate

 * 1) Physically set the duplicate up as the boot disk. Change cables and/or jumpers; some systems require a reference disk to tell the computer that you only have one hard drive.
 * 2) Start from the HPFS386 Recovery Disk.
 * 3) Type ftboot and press ENTER.
 * 4) Insert the LAN Manager OS/2 Disk 1 when prompted.
 * 5) Start from the newly created boot volume.

Install a new disk, then use Ftsetup to unmirror the boot volume.

