Backup error on a Plesk server: database is locked

Symptoms

• Error in Plesk Backup Manager during the backup creation:

  The following errors occurred during the scheduled backup process:
  database is locked

• Error in backup log /var/log/plesk/PMM/pmmcli.log:

  CRITICAL: Runtime error in pmmcli:
  <class 'sqlite3.OperationalError'> database is locked
  Traceback (most recent call last):
  File "/usr/local/psa/admin/sbin/pmmcli/pmmcli.py", line 2543, in main
  File "/usr/local/psa/admin/sbin/pmmcli/pmmcli.py", line 2442, in get_task_status
  File "/usr/local/psa/admin/sbin/pmmcli/pmmcli.py", line 102, in doActivity
  File "/usr/local/psa/admin/sbin/pmmcli/pmmcli.py", line 1999, in doActivity
  File "/usr/local/psa/admin/sbin/pmmcli/pmm_task.py", line 1517, in getTaskStatus
  result = self.__taskFinder(task_id,self.operatorGetTaskStatus)
  File "/usr/local/psa/admin/sbin/pmmcli/pmm_task.py", line 1369, in __taskFinder
  task = self.persistent_storage.getTask(task_id)
  File "/usr/local/psa/admin/sbin/pmmcli/pmm_task.py", line 840, in getTask
  return self.__loadTask(task_id)
  File "/usr/local/psa/admin/sbin/pmmcli/pmm_task.py", line 828, in __loadTask
  return Task.load(loader)
  File "/usr/local/psa/admin/sbin/pmmcli/pmm_task.py", line 496, in load
  self = pload()
  File "/usr/local/psa/admin/sbin/pmmcli/pmm_task.py", line 85, in load
  cursor.execute('SELECT dump FROM tasks WHERE id=?', [self.__task_id])
  sqlite3.OperationalError: database is locked

Cause

Bug in Plesk with ID #PPPM-14943.

Resolution

No resolution yet. As a workaround increase the timeout for pmm-cli:

1. Connect to the server via SSH

2. Using vi edit the file /usr/local/psa/admin/share/pmmcli/pmmcli-rc and set the timeout to higher value that 1. For example to 300:

   DAEMON_TIMEOUT 300