Backup/restoration process fails in Plesk: Cannot stat: Permission denied /bin/tar: Error is not recoverable

Symptoms

• A backup/restoration process completes with the following error message in Plesk:

  PLESK_WARN: Cannot stat: Permission denied /bin/tar: Error is not recoverable: exiting now

• Migration fails with the following error message:

  PLESK_ERROR: Failed to import backup dumps to target panel's repository
  Cause: Failed to import backup XML: errcode must be '0' (no errors) or '116' (backup sign error).
  Output of pmmcli utility:
  <?xml version="1.0" encoding="UTF-8"?>
  <response>
  <errcode>199</errcode>
  <errmsg>Unable to import file as dump: pmm-ras failed (Error code = 1):
  STDOUT: migra_info_1909102106.xml
  boost::filesystem::status: Input/output error: "/backup_dir/tmp/pmm-dudc-incApacheFiles-KH7Bjv"
  STDERR: </errmsg>
  </response>

Cause

The DUMP_TMP_D location shares the same directory as DUMP_D causing permission conflict.

# grep DUMP /etc/psa/psa.conf
DUMP_D /backup/dumps
DUMP_TMP_D /backup/dumps

Resolution

1. Connect to the Plesk server via SSH.

2. Change the DUMP_TMP_D location to a directory which is different from DUMP_D using the steps from this KB article. For example:

   # grep DUMP /etc/psa/psa.conf
   DUMP_D /backup/dumps
   DUMP_TMP_D /backup/dumptemp

3. Set the correct directory permissions and ownership using these commands:

   # chown psaadm:psaadm /backup/dumps

   # chmod 755 /backup

   # chmod 755 /backup/dumps

   # chmod 1777 /backup/dumptemp/