Description of problem: In order to collect error messages I started dnfdragora-updater from the command line.  Several days later after doing "dnf check-update" and seeing updates were available I clicked on the icon in the systray and picked "Open dnfdragora dialog".  The screen appeared with a spinning cursor which never stopped.  The following message appeared in the terminal where dnfdragora-updater was started.

[egreshko@meimei ~]$ Skipped exception: <[Errno 2] No such file or directory: './dnfdragora.yaml'> 
<_M_> [mga-qt-ui] YMGA_QCBTable.cc:74 YMGA_QCBTable():  Slection mode 2
Traceback (most recent call last):
  File "/usr/lib/python3.6/site-packages/pystray/_base.py", line 236, in inner
    callback(self)
  File "/usr/lib/python3.6/site-packages/pystray/_base.py", line 320, in __call__
    return self._action(icon, self)
  File "/usr/lib/python3.6/site-packages/pystray/_base.py", line 414, in wrapper1
    return action(icon)
  File "/usr/lib/python3.6/site-packages/dnfdragora/updater.py", line 109, in __run_dnfdragora
    return self.__run_dialog({})
  File "/usr/lib/python3.6/site-packages/dnfdragora/updater.py", line 104, in __run_dialog
    self.__main_gui = ui.mainGui(args)
  File "/usr/lib/python3.6/site-packages/dnfdragora/ui.py", line 214, in __init__
    rpm_groups = self.backend.GetGroups()
  File "/usr/lib/python3.6/site-packages/dnfdragora/basedragora.py", line 50, in backend
    return self.get_root_backend()
  File "/usr/lib/python3.6/site-packages/dnfdragora/basedragora.py", line 77, in get_root_backend
    self.backend.ExpireCache()
  File "/usr/lib/python3.6/site-packages/dnfdaemon/client/__init__.py", line 401, in ExpireCache
    rc = self._run_dbus_async('ExpireCache', '()')
  File "/usr/lib/python3.6/site-packages/dnfdaemon/client/__init__.py", line 293, in _run_dbus_async
    result = self._get_result(data)
  File "/usr/lib/python3.6/site-packages/dnfdaemon/client/__init__.py", line 277, in _get_result
    self._handle_dbus_error(user_data['error'])
  File "/usr/lib/python3.6/site-packages/dnfdaemon/client/__init__.py", line 250, in _handle_dbus_error
    raise DaemonError(str(err))
dnfdaemon.client.DaemonError: g-io-error-quark: GDBus.Error:org.freedesktop.DBus.Python.OSError: Traceback (most recent call last):
  File "/usr/lib64/python3.6/site-packages/dbus/service.py", line 707, in _message_cb
    retval = candidate_method(self, *args, **keywords)
  File "/usr/lib/python3.6/site-packages/dnfdaemon/server/__init__.py", line 83, in newFunc
    rc = func(*args, **kwargs)
  File "/usr/share/dnfdaemon/dnfdaemon-system", line 175, in ExpireCache
    rc = self.expire_cache()
  File "/usr/lib/python3.6/site-packages/dnfdaemon/server/__init__.py", line 240, in expire_cache
    self.base.setup_base()
  File "/usr/lib/python3.6/site-packages/dnfdaemon/server/backend.py", line 69, in setup_base
    self.fill_sack()
  File "/usr/lib/python3.6/site-packages/dnf/base.py", line 316, in fill_sack
    try:
  File "/usr/lib/python3.6/site-packages/dnf/base.py", line 114, in _add_repo_to_sack
    def _add_repo_to_sack(self, repo):
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 919, in load
    self._handle_load(handle)
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 657, in _handle_load
    return self._handle_load_core(handle)
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 670, in _handle_load_core
    result = handle._perform()
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 229, in _perform
    return super(_Handle, self).perform(result)
  File "/usr/lib64/python3.6/site-packages/librepo/__init__.py", line 1517, in perform
    _librepo.Handle.perform(self, result)
OSError: [Errno unknown] Cannot prepare internal mirrorlist: dup(1012) failed: Too many open files: 'Input/Output error'
 (36)




Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
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Actual results:


Expected results:  Expect it to work.


Additional info: