[Satellite 5.4] cobbler service fails with ReaderError: unacceptable character #x0000: special characters are not allowed in "<string>", position 42

Solution Verified - Updated -

Environment

  • Red Hat Network (RHN) Satellite 5.4

Issue

  • getting error message when cobbler fails to start
    [root@satellite]# service cobblerd start
Starting cobbler daemon: Traceback (most recent call last):
  File "/usr/bin/cobblerd", line 76, in main
    api = cobbler_api.BootAPI(is_cobblerd=True)
  File "/usr/lib/python2.4/site-packages/cobbler/api.py", line 128, in __init__
    self.deserialize()
  File "/usr/lib/python2.4/site-packages/cobbler/api.py", line 689, in deserialize
    return self._config.deserialize()
  File "/usr/lib/python2.4/site-packages/cobbler/config.py", line 208, in deserialize
    serializer.deserialize(self._profiles)
  File "/usr/lib/python2.4/site-packages/cobbler/serializer.py", line 122, in deserialize
    rc = storage_module.deserialize(obj,topological)
  File "/usr/lib/python2.4/site-packages/cobbler/modules/serializer_catalog.py", line 186, in deserialize
    datastruct = deserialize_raw(obj.collection_type())
  File "/usr/lib/python2.4/site-packages/cobbler/modules/serializer_catalog.py", line 158, in deserialize_raw
    datastruct = yaml.load(ydata)
  File "/usr/lib64/python2.4/site-packages/yaml/__init__.py", line 57, in load
    loader = Loader(stream)
  File "/usr/lib64/python2.4/site-packages/yaml/loader.py", line 34, in __init__
    Reader.__init__(self, stream)
  File "/usr/lib64/python2.4/site-packages/yaml/reader.py", line 114, in __init__
    self.determine_encoding()
  File "/usr/lib64/python2.4/site-packages/yaml/reader.py", line 170, in determine_encoding
    self.update(1)
  File "/usr/lib64/python2.4/site-packages/yaml/reader.py", line 204, in update
    self.check_printable(data)
  File "/usr/lib64/python2.4/site-packages/yaml/reader.py", line 179, in check_printable
    'unicode', "special characters are not allowed")
ReaderError: unacceptable character #x0000: special characters are not allowed
  in "<string>", position 42
                                                           [  OK  ]

Resolution

  • Search for all files in /var/lib/cobbler/config/*.d/* with name not ending in .json, and make sure it does not contain any special characters.

  • If necessary, try to narrow it down with attached (unofficial/unsupported) debug patches serializer_catalog.py.TEST.00557951.1.patch and reader.py.TEST.00557951.1.patch, which applies to /usr/lib/python2.4/site-packages/cobbler/modules/serializer_catalog.py and /usr/lib64/python2.4/site-packages/yaml/reader.py respectively.  Then restart cobbler service to get the debug output (there will be alot since the debug patches try to print out file's name and content).

Root Cause

The traceback indicates that in some file (whose name does not end in .json) among /var/lib/cobbler/config/*.d/* there's a special character (unicode #x0000). This causes cobbler start/initialization to fail.

Attachments

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