Frozen tapes

DOCUMENTATION: How to troubleshoot frozen media on UNIX and Windows
http://support.veritas.com/docs/249632

Details:
Manuals:
NetBackup (tm) 4.x, 5.x Troubleshooting Guide for UNIX and Windows
NetBackup (tm) 4.x, 5.x Media Manager System Administrator's Guide for UNIX and Windows

Modification Type: Addition

Modification:
When troubleshooting frozen media issues, it is important to understand the following:


The actual FROZEN status is stored in the media database (MediaDB) of the media server that froze the media. Every media server (including the master) has its own unique media database (MediaDB).
MediaDB information, including the media status (Frozen, Full, Active), can be obtained using the bpmedialist command.
Media can only be unfrozen by using the bpmedia command. When media is unfrozen, the media server containing that frozen record should be specified in the command syntax. Media must be unfrozen one at a time.
A media being frozen does not necessarily mean that the media in question is defective. Freezing media is a safety measure taken by the NetBackup application to help prevent further errors, drive damage, or possible data loss.
Investigate if there is any pattern to the media IDs, tape drives or media servers involved when media are frozen


The following logs are useful when troubleshooting frozen media:

UNIX:

The bptm log from the media servers that froze the media: /usr/openv/netbackup/logs/bptm
The Admin messages or syslog from the OS

Windows

The bptm log from the media servers that froze the media: <Install_dir>\VERITAS\NetBackup\logs\bptm
The Windows Event Viewer System Log
The Windows Event Viewer Application Log

Note: It is preferable to have bptm enabled at a verbosity of 5 to troubleshoot any media and drive related issues. The bptm process log does not tend to take up excessive drive space or resources, even at an elevated verbosity. When a media is frozen, the bptm logs may contain more detailed information on why the media was frozen that the Activity Monitor or Problems Report does not state. Verbosity on bptm must be increased for every media server individually by changing its logging levels under Host Properties in the Administration console.

The following Status Codes can cause, or be a result of frozen media:
Status Code Reason
84 - Media Write Error If the tape unit can not read or write to the tape correctly, this status code can occur when media are frozen
86 - Media Position Error If the tape unit can not read or write to the tape correctly, this status code can occur when media are frozen
96 - Unable to allocate new media If media continue to become frozen, the backup job may end in a Status 96, because no more media available to mount.



The following are six common situations in which media become frozen:

1. The same media has excessive errors during backup

FREEZING media id E00109, it has had at least 3 errors in the last 12 hour(s)

Common causes and resolutions for this include:

Dirty drives. Clean the drives that are freezing media. One of the first symptoms seen with a dirty drive is often frozen media. Drive cleaning should be done according to the manufacturer's suggestions.
There may be an issue with the drive itself. Check the OS system logs mentioned above for any errors regarding tape devices or errors reported by the driver for the tape device. If any are found, follow the hardware manufacturer's recommendations for this type of error.
There may be an issue with communication at the SCSI or Host Bus Adapter (HBA) level. Check the OS system logs mentioned above for any errors regarding SCSI or HBA devices or errors reported by their driver. If any are found, follow the hardware manufacturer's recommendations for this type of error.
Ensure that the tape drives appear on the hardware compatibility list as supported for NetBackup. This list is located on the Symantec Technical Support Web site: http://support.veritas.com/menu_ddProduct_NBUESVR_view_CL.htm
Ensure that the media is supported for use with the tape drive by the tape drive vendor


2. An unexpected media is found in the drive

Incorrect media found in drive index 2, expected 300349, found 200244, FREEZING 300349

This can occur under the following circumstances:

If NetBackup requests a media ID to be mounted in a drive and the media ID physically recorded on the tape is different than that NetBackup media ID, media will freeze. This can happen if the robot needs to be inventoried, if barcodes have been physically changed on the media, or if the media was previously written to by another NetBackup installation with different barcode rules.
The drives in the robot are not configured in order within NetBackup, or are configured with the wrong tape paths. Configuration of drives using the correct Robot Drive Number is important to the proper mounting and utilization of media. The Robot Drive Number, commonly set based on co-relation of the drive serial number with drive serial number information from the robotic library, should be determined and validated before the device configuration is considered complete.


3. The media contain a non-NetBackup format

FREEZING media id 000438, it contains MTF1-format data and cannot be used for backups
FREEZING media id 000414, it contains tar-format data and cannot be used for backups
FREEZING media id 000199, it contains ANSI-format data and cannot be used for backups

These are usually tapes written outside of NetBackup that have found their way into the library. By default, NetBackup will only write to a blank media or other NetBackup media. Other media types (DBR, TAR, CPIO, ANSI, MTF1 and recycled Backup Exec BE-MTF1 media) will be frozen as a safety measure. This behavior can be changed with the following procedure:

UNIX
To allow NetBackup to overwrite foreign media, add the following to /usr/openv/netbackup/bp.conf for the media server in question:

ALLOW_MEDIA_OVERWRITE = DBR
ALLOW_MEDIA_OVERWRITE = TAR
ALLOW_MEDIA_OVERWRITE = CPIO
ALLOW_MEDIA_OVERWRITE = ANSI
ALLOW_MEDIA_OVERWRITE = MTF1
ALLOW_MEDIA_OVERWRITE = BE-MTF1

Stop and restart the NetBackup daemons for the changes to take effect

Windows
1. From the Administration Console, proceed to Host Properties | Media Server
2. Open the properties for the media server in question
3. Select the Media tab

The Allow Media Overwrite property overrides the NetBackup overwrite protection for specific media types. To disable overwrite protection, select one or more of the listed media formats

Stop and restart the NetBackup services for the changes to take effect.

Caution: Do not select a foreign media type for overwriting unless it is certain that this media type should be overwritten. For more details on what each media type is, see the NetBackup System Administrator's Guide.


4. The media was formerly a tape used for the NetBackup Catalog backup

FREEZING media id 000067: it contains VERITAS NetBackup (tm) database backup data and cannot be used for backups.

This media was frozen because it is an old catalog backup tape which NetBackup will not overwrite by default. In this case, the media must be labeled with the bplabel command to reset the media header (see Related Documents below).

5. Media was intentionally frozen

It is possible to manually freeze media with the bpmedia command for a variety of administrative reasons. If frozen media are encountered and there is no record of a specific job freezing the media, media may have manually been frozen.

6. Media is physically write protected

If the media has a write protect notch that is set for write protection, this will prevent any writing to the media and NetBackup will freeze it.


Unfreezing frozen media:

To unfreeze frozen media, use the bpmedia command with the following syntax:

For UNIX
/usr/openv/netbackup/bin/admincmd/bpmedia -unfreeze -m <mediaID> -h <name of media server that froze media>

For Windows
<Install_path>\VERITAS\Netbackup\bin\admincmd\bpmedia -unfreeze -m <mediaID> -h <name of media server that froze media>

If it is not known which media server froze the media, run the bpmedialist command and note the "Server Host:" listed in the output:

For UNIX
/usr/openv/netbackup/bin/admincmd/bpmedialist -m <mediaID>

For Windows
<Install_path>\VERITAS\Netbackup\bin\admincmd\bpmedialist -m <mediaID>

See the text illustration below for a sample output. In this example, bpmedialist is run for the frozen media div008. It is found in this example that the media server "denton" froze this media.

C:\Program Files\VERITAS\NetBackup\bin\admincmd>bpmedialist -m div008

Server Host = denton

ID rl images allocated last updated density kbytes restores
vimages expiration last read <------- STATUS ------->
----------------------------------------------------------------------------------------------------------

DIV008 1 1 04/22/2005 10:12 04/22/2005 10:12 hcart 35 5
1 05/06/2005 10:12 04/22