Ref: 11640024
Title: Maintaining 3Com Server Disks
date: 6/28/89

Copyright 3Com Corporation, 1991.  All rights reserved.

Over time, even 3Com dedicated server disks will develop defects
due to power failures, adverse environmental conditions, and
normal mechanical wear.  It is important to identify new defects
as soon as possible to keep the server operating optimally.



Symptoms of Disk Defects

If a server disk has defects, CIOSYS errors will appear in the
\3root\STAT_LOG file.  They look like this:

02-Sep-88 06:12:00 CIOSYS  4 I/O error B on drive C:, sector 4A7D
16-Sep-88 06:09:00 CIOSYS  4 I/O error B on drive C:, sector 4639

Usually several CIOSYS errors appear together in the status file.

To check the file for CIOSYS errors, follow these steps:

1.  Log in to the server as a user or administrator.

2.  Type 3F LINK F: \\SYS\3ROOT and press [Return].

3.  Type CD F: and press [Return].

4.  Type STATUS and press [Return].

    The STAT_LOG file will display on screen.



When to Perform the Server Disk Maintenance Procedure

    For all servers                            Once a year

    For heavily used servers (servers          Quarterly
    storing large files that are updated
    daily)

    For servers with suspected disk defects    Immediately

If possible, it is best to check for server disk defects during
"worst-case" conditions, such as when the room's air conditioner
is shut off or when the equipment is experiencing power
fluctuations.

While performing disk maintenance, the server cannot be used for
normal operations.  For 3S/201 servers, it is recommended that
you have 24 hours to complete the server disk maintenance
procedure.  For 3S/401 servers, you will need six hours to
complete the procedure.  The "write-read" tests are the longest
part of the procedure and should be set to run overnight, if
possible.



Before You Begin

You will need the following materials:

1.  DOS Netstation Startup diskette.

2.  3+ 1.3.1 System Software diskette #1.

3.  3+Backup 1.3.1 #2 diskette.

    Note:  This procedure will not work with a System
    Software diskette or 3+Backup diskette below 1.3.1.

4.  Two blank tapes, such as the 3M 600XTD, 3M DC6150, or Dysan
    612.

5.  A tape unit on each server to be maintained.


How to Maintain Your Server Disks

There are two parts to the maintenance procedure.  The first part
is to make two off-line backups of all files on the server.  The
second part is to format the server disk drive and restore the
data to the disk.

It is a good idea to read through all of the instructions before
you begin the procedure.

PART I

1.  Shut down all services if the server is on-line.

    Be sure to notify the users that the server is being shut
    down, or do your off-line backup during non-working hours.

    To shut down the services, follow these steps:

    A.  Insert the Netstation Startup disk into netstation drive
        A:.

    B.  At the A> prompt type LOGIN ADMIN and press [Return] to
        log in as the administrator.  Then enter the
        administrator password if one is required.

    C.  At the A> prompt type 3F LINK D: \\SYS\APPS and press
        [Return].

    D.  At the A> prompt type D: and press [Return].

    E.  If the server has 3+Mail service, at the D> prompt type
        3M SHUTDOWN and press [Return].

        When asked to confirm the shutdown, type Y and press
        [Return].

    F.  At the D> prompt, type 3P SHUTDOWN and press [Return].

        When asked to confirm the shutdown, type Y and press
        [Return].

    G.  If the server has 3+Name service, type 3N SHUTDOWN and
        press [Return].

        When asked to confirm the shutdown, type Y and press
        [Return].

2.  At the server, open the front panel and put the server into
    TEST or MAINTENANCE mode.

    For a 3S/201, toggle the Operate/Test switch to TEST (right).

    For a 3S/401, set the Mode switch to MAINTENANCE (middle).

3.  Set the thumbwheel switch.

    For a 3S/201, set the switch to 4.

    For a 3S/401, set the switch to 1 for Ethernet or 2 for token
    ring.

4.  Press the Reset button.

    The Ethernet address of your server displays on the LCD.   If
    you do not know the address, make a note of it because you
    will be asked to confirm it.

5.  Insert 3+ System Software diskette #1 in netstation drive A:.

    This contains the 3C program that you use to bring up the
    server off-line.

6.  Type 3C START and press [Return].

    On the netstation screen you will see a message asking you to
    confirm the server's Ethernet address.

7.  Type Y to confirm the address, if it is correct.

    There is a pause while the server reboots.  Wait for REMOTE
    ACTIVE to appear on the server's LCD.  Then you will see the
    A:\>> prompt on the netstation screen.

8.  Insert the 3+Backup #2 diskette in netstation drive A:.

9.  At the A:\>> prompt, type 3BMENDOS and press [Return] to
    start 3+Backup off-line.

    The 3+Backup main menu is displayed.

10. Insert a blank tape into the server tape drive.

11. Select "Erase tape."

    If you use a new tape, erase the tape TWICE to adjust the
    tape tension for normal use before backing up data.

12. When the tape has been erased, select "Backup."

13. Press CTRL-Return to perform a full system backup.

    You will receive a confirmation message when the backup is
    complete.

14. After the first backup, remove the tape from the drive and
    insert another tape for the second backup.

15. Erase the tape once or twice as needed.  Then select "Backup"
    again from the menu.

16. When you have completed two backups, select "Quit."

17. Type Y to confirm you are quitting the Backup menu.

18. Check to see if your backups were successful.

    A.  Type C: to change to drive C:.

        You will see the prompt C:\>>.

    B.  Type CD \3PLUS\3BACKUP and press [Return].

    C.  Type TYPE STAT_LOG and press [Return].

    D.  Check the log to see if your backups were successful.  If
        the backups completed successfully, the listing with the
        date and time you ran each backup should say "Completion
        status:  Successful."

19. If either backup was not completed successfully, fix the
    drive where the backup failed.

    A.  Type TYPE BACK_LOG to see where the backup stopped.

        BACK_LOG will list the file, including its drive ID,
        where the backup stopped.

    B.  Note the drive ID where the backup stopped.

    C.  Type CHKDSK /F x:, where "x" is the drive ID of the drive
        where the backup stopped, and press [Return].

        In most cases, CHKDSK will fix the sector where the
        backup stopped; however, you may need to run it several
        times.

    D.  Redo the backup (steps 9-18 above).

20. Type CD \ and press [Return] to go to the C:\>> prompt.

21. Type A: and press [Return] to go to the A:\>> prompt.

    Continue with Part II below.




PART II

Follow the steps appropriate for the type of server you have.


For 3S/201 Servers:

1.  At the A:\>> prompt, type 3DISK and press [Return].

2.  Type 1 and press [Return] to select "Choose Disk."

3.  Type 0 and press [Return] to select the default SCSI bus ID.

4.  Type 0 and press [Return] to select the default disk ID.

5.  Note the configuration of the disk partitions.

    A.  Select "Show configuration."

    B.  Select "Show DOS configuration."

    C.  For each partition of the disk, write down the bytes per
        sector, sectors per cluster, sectors in partition, and
        the size of the partition.  You must have this
        information to reformat the disk properly.

    D.  Press ESC to return to the main menu.

6.  Select "Diagnose hardware."

7.  Run a write-read test once to make sure the error log does
    not fill up.

    A.  Select "Run write-read test."

        The write-read test overwrites all data from the drive.

    B.  Type Y twice to confirm that you want to overwrite the
        data.

    C.  At "How many passes" type 1.  Each pass takes 16 minutes.

8.  Check the error log to see if there are errors listed.

    A.  Press ESC to return to the main menu.

    B.  Select "Show configuration and tables."

    C.  Select "Show error log."

9.  If there are any errors listed, perform a recover without
    format.

    A.  Press ESC to return to the main menu.

    B.  Select "Recover without format."

    C.  Select "Confirm logged defects."

    D.  Press ESC to return to the main menu.

10. Run the write-read test 75 times.

    A.  Select "Diagnose hardware."

    B.  Select "Run write-read test" and type Y twice to confirm
        that you will overwrite the data.

    C.  At "How many passes" type 75.

        The write-read test will take hours to run, but it is the
        best test because it is the most stringent.  If you have
        serious time constraints, complete as many passes as time
        allows.

        Note:  If a RLL controller was added to upgrade a 70 MB
        drive to 106 MB, it is strongly recommended that you
        perform the 24-hour write-read test.  The RLL controller
        writes more densely than other controllers and therefore
        may find more unacceptable sectors.

11. After the write-read tests are completed, verify the defects.

    A.  Press ESC to return to the main menu.

    B.  Select "Format."

    C.  Select "Sort defect log into defect map."

12. When the defect log has been sorted into the defect map,
    select "Normal Format" to format the disk.

13. Type Y to confirm you will erase all data on disk.

14. Type Y to confirm that you have sorted errors into the defect
    map.

    In the format, you will be asked to accept default values or
    enter new values for these variables in each partition of the
    disk:

         Bytes per sector
         Sectors per cluster
         Sectors in partition
         Number of root directory entries

15. At each prompt, enter the values that you noted before the
    write-read test from the "Show DOS configuration" table.

    When you have finished entering the correct values, you will
    see the message "Restart the 3Server before loading
    software!"

16. Press ESC to leave the Format submenu.

17. Press ESC to leave the main menu.

18. Under the front panel, change the thumbwheel to 4.

19. When prompted whether or not to automatically reboot the
    server, type Y and press [Return].

20. At the A:\> prompt, type 3C /START and press [Return].

21. Type Y to confirm the address, if it is correct.

22. Press [Return] when the server displays "Remote Active."

23. Insert the 3+Backup #2 disk in netstation drive A:.

24. At the A:\>> prompt, type 3BMENDOS and press [Return].

    The 3+Backup main menu will be displayed.

25. Insert one of your backup tapes in the tape unit.

26. If you are not sure of the server's three-part name, select
    "Identify tape," note the name when it appears on screen, the
    press ESC to return to the main menu.

27. Restore the data from the backup tape.

    A.  Select "Restore partitions."

    B.  At "Source server" enter the full three-part server name.

    C.  For each restore variable, press [Return] to accept the
        default value.

    D.  Type Y and press [Return] to confirm that you want to
        restore the backup tape.

    When the restore is complete, you will be returned to the
    main menu.

28. Select "Quit."

29. Type Y and press [Return] to leave the 3BMENDOS menu.

30. At "Insert disk with COMMAND.COM in drive A:" put the 3+
    System Software diskette #1 in netstation drive A:.

    You will see the A:\>> prompt again.

31. Restart the server.

    A.  Open the server's front panel and turn the thumbwheel to
        0.

    B.  Press the Reset button.

    C.  Move the toggle switch to Operate (left).

    The server should display the server name, date, and time.



For 3S/401 Servers:

1.  At the A:\>> prompt, type 3DISK386 and press [Return].

    The 3DISK386 main menu appears.

2.  Press 1 to select "Choose disk."

3.  Press [Return] to select the default disk value.

4.  Select the appropriate SCSI bus ID.

    For example, press 2 to select a base unit or press 3 to
    select a disk expansion unit.

5.  At "Enter the SCSI LUN number" press [Return] to accept the
    default value.

6.  At "Is this a bootable drive" type Y and press [Return] to
    confirm the drive is bootable.

    After confirming the drive is bootable, you will be prompted
    for responses to a series of variables.

7.  Press [Return] to accept the default values until you see the
    3D> prompt again.

8.  At the 3D> prompt, press [Return] to see the 3DISK386 main
    menu.

9.  Note the configuration of the disk partitions.

    A.  Select "Show configuration."

    B.  Select "Show DOS configuration."

    C.  For each partition of the disk, write down the bytes per
        sector, sectors per cluster, sectors in partition, and
        the size of the partition.  You must have this
        information to reformat the disk properly.

    D.  Press ESC to return to the main menu.

10. Select "Diagnose hardware."

11. Select "Run write-read test."

    The write-read test erases all data from the drive.

    The write-read test may take hours to run, but it is the best
    test because it is the most stringent.  If you have serious
    time constraints, select the read-only "verify disk" test
    instead.

    The write-read or verify disk test enters any new defects
    into the cumulative list.  The verify disk test does not
    erase data from the drive.

12. Type Y to confirm that you want to run the write-read test.

13. After the write-read test is completed, check the cumulative
    error list.

    A.  Press ESC to return to the main menu.

    B.  Press [Return] to see the menu selections again.

    C.  Select "Manage defects."

    D.  Select "Display cumulative defect list."

14. If defects are listed in the cumulative defect list, perform
    a hard format.

    A.  Press ESC to return to the main menu.

    B.  Press [Return] to see the menu selections again.

    C.  Select "Format disk."

    D.  Type Y and press [Return] to confirm the format.

    The hard format sorts defects into the defect map and
    renumbers the disk sectors.  This makes the sectors
    contiguous again, which may reduce disk seek time.

    For each volume, you will be prompted for the number of bytes
    per sector, cluster size and megabytes in the volume.

15. At each prompt, enter the values that you noted before the
    write-read test from the "Show DOS configuration" table.

16. If using a version of 3DISK386 that includes 3+Open, choose
    the appropriate operating system when prompted.

    There is a difference in the maximum number of clusters per
    volume:  16384 for DOS versus 65536 for OS/2.

    When the format is complete, you will see the message "Format
    completed successfully."

17. Press ESC to leave the 3D> prompt.

    You will see the message "Please reset server."

18. Under the front panel, change the thumbwheel setting to 1 and
    press the Reset button.

19. Insert the 3+ System Software diskette #1.

20. At the A:\> prompt, type 3C START and press [Return].

21. Type Y to confirm the address, if it is correct.

22. Insert the 3+Backup #2 disk in netstation drive A:.

23. At the A:\>> prompt, type 3BMENDOS and press [Return].

    The 3+Backup main menu will be displayed.

24. Insert one of your backup tapes in the tape unit.

25. If you are not sure of the server's three-part name, select
    "Identify tape," note the name when it appears on screen,
    then press ESC to return to the main menu.

26. Restore the data from the backup tape.

    A.  Select "Restore partitions."

    B.  At "Source server" enter the full three-part server name.

    C.  For each restore variable, press [Return] to accept the
        default value.

    D.  Type Y and press [Return] to confirm that you want to
        restore the backup tape.

    When the restore is complete, you will be returned to the
    main menu.

27. Select "Quit."

28. Type Y and press [Return] to leave the 3BMENDOS menu.

29. At "Insert disk with COMMAND.COM in drive A:" put the 3+
    System Software diskette #1 in netstation drive A:.

    You will see the A:\>> prompt again.

30. Restart the server.

    A.  Open the server's front panel and turn the thumbwheel to
        0.

    B.  Press the Reset button.

    C.  Move the Mode switch to the server position (far left).

        The server should display the server name, date, and time.




Further Tuning

In addition to regularly identifying defects on the server, it
may be helpful to adjust cluster sizes on the disk to keep disk
response time as low as possible.  For a server with database
files or large files that are downloaded periodically from a
mainframe, it is helpful to assign large cluster sizes.  For a
server with many small files, it is helpful to assign small
cluster sizes.  Consult your 3Com network tuning documentation
for more information.
