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  1. Home
  2. NetBackup™ Status Codes Reference Guide
  3. NetBackup status codes
  4. NetBackup status codes
  5. NetBackup status code: 84
NetBackup™ Status Codes Reference Guide

NetBackup status code: 84

Message: media write error

Explanation: The system's device driver returned an I/O error while NetBackup wrote to removable media or a disk file.

Recommended Action: Do the following, as appropriate:

  • For NetBackup Snapshot Client only:

    If the following message appears in the /usr/openv/netbackup/bptm log, and the values for key, asc, and ascq are all zero (0x0) as shown in this example message:

    tape error occurred on extended copy command, key = 0x0, asc = 
    0x0, ascq = 0x0

    NetBackup Snapshot Client probably does not support your host-bus adapter and its driver. The host-bus adapters that are supported in the release are listed in the NetBackup Release Notes.

  • For additional information, check the following:

    • NetBackup Problems report to determine the device or media that caused the error

    • System and error logs for the system (UNIX)

    • Event Viewer Application and System logs (Windows)

  • If NetBackup writes backups to a disk file, verify the following: The fragment size that is configured for the disk storage unit is not greater than the maximum file size that the operating system specifies.

  • On Windows, make sure that the tapes are not write protected.

  • If bpbackupdb was used to back up the NetBackup catalog to a disk path on a UNIX or Linux system, the image you try to write may be greater than the maximum file size that is specified by that operating system. Tape files do not have this limit. You may have to back up the catalog to tape.

  • If the media is tape, check for the following:

    • A defective or a dirty drive. Clean it or have it repaired (refer to the tpclean command for robotic drives).

    • The wrong media type. Verify that the media matches the drive type you use.

    • Defective media. If it is defective, use the bpmedia command to set the volume to the FROZEN state so it is not used for future backups.

    • Incorrect drive configuration. Verify the Media and Device Management and system configuration for the drive.

      For example, on UNIX the drive may be configured for fixed mode when it must be variable mode.

      See the NetBackup Device Configuration Guide for more information.

      This configuration often results in the media being frozen with the message

      too many data blocks written, check tape and drive block size 
      configuration

      See "Frozen media troubleshooting considerations" in the NetBackup Troubleshooting Guide.

  • If you receive this error message when a GLACIER or LIFECYCLE backup job fails, the error is related to the Amazon lifecycle policy and occurs in the following situations:

    • The Amazon lifecycle policy that NetBackup uses cannot be applied. The Amazon GLACIER or LIFECYCLE storage class is not supported for the region to which the bucket belongs. Recreate the disk pool with the bucket in the supported region.

    • A different Amazon lifecycle policy other than what NetBackup uses already exists. Remove the policy that is not used by NetBackup and rerun the job.

    • The error occurred while creating the Amazon lifecycle policy that NetBackup uses to back up data to Amazon. Check the bptm logs for more details.

Click here to view technical notes and other information on the Cohesity Technical Support website about this status code.

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