Pulpcore 3.7 repository sync is hanging

In preparation of 3.17.1 I have set up the new pulpcore 3.7 repository in my 3.17.0 katello server and started a sync. It’s is however hanging at New packages: 159/160 (49.5 MB/49.5 MB).

I have noticed an error message in /var/log/messages which seems to match the issue:

Dec 10 07:42:06 foreman pulp: nectar.downloaders.threaded:ERROR: (2784-63840) Unhandled Exception in Worker Thread [140420680963840]
Dec 10 07:42:06 foreman pulp: nectar.downloaders.threaded:ERROR: (2784-63840) Traceback (most recent call last):
Dec 10 07:42:06 foreman pulp: nectar.downloaders.threaded:ERROR: (2784-63840)   File "/usr/lib/python2.7/site-packages/nectar/downloaders/threaded.py", line 187, in worker
Dec 10 07:42:06 foreman pulp: nectar.downloaders.threaded:ERROR: (2784-63840)     self._fetch(request, session)
Dec 10 07:42:06 foreman pulp: nectar.downloaders.threaded:ERROR: (2784-63840)   File "/usr/lib/python2.7/site-packages/nectar/downloaders/threaded.py", line 348, in _fetch
Dec 10 07:42:06 foreman pulp: nectar.downloaders.threaded:ERROR: (2784-63840)     if nretry < DEFAULT_GENERIC_TRIES - 1 and e.args[1] == errno.ECONNRESET:
Dec 10 07:42:06 foreman pulp: nectar.downloaders.threaded:ERROR: (2784-63840) IndexError: tuple index out of range

However, I don’t really find anything beyond that, so it’s unclear to me what exactly causes the problem.

Running an advanced validate content sync shows a few more errors:

Dec 10 07:55:57 foreman pulp: nectar.downloaders.threaded:ERROR: (51257-79488) Unhandled Exception in Worker Thread [140420466079488]
Dec 10 07:55:57 foreman pulp: nectar.downloaders.threaded:ERROR: (51257-79488) Traceback (most recent call last):
Dec 10 07:55:57 foreman pulp: nectar.downloaders.threaded:ERROR: (51257-79488)   File "/usr/lib/python2.7/site-packages/nectar/downloaders/threaded.py", line 187, in worker
Dec 10 07:55:57 foreman pulp: nectar.downloaders.threaded:ERROR: (51257-79488)     self._fetch(request, session)
Dec 10 07:55:57 foreman pulp: nectar.downloaders.threaded:ERROR: (51257-79488)   File "/usr/lib/python2.7/site-packages/nectar/downloaders/threaded.py", line 378, in _fetch
Dec 10 07:55:57 foreman pulp: nectar.downloaders.threaded:ERROR: (51257-79488)     if nretry < DEFAULT_GENERIC_TRIES - 1 and e.args[1] == errno.ECONNRESET:
Dec 10 07:55:57 foreman pulp: nectar.downloaders.threaded:ERROR: (51257-79488) IndexError: tuple index out of range
Dec 10 07:55:58 foreman pulp: pulp_rpm.plugins.importers.yum.sync:INFO: [79952a84] Generating metadata databases.
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:INFO: [79952a84] Determining which units need to be downloaded.
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.repomd.packages:ERROR: [79952a84] failed to parse XML metadata file
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848) no element found: line 1, column 0
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848) Traceback (most recent call last):
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)   File "/usr/lib/python2.7/site-packages/pulp_rpm/plugins/importers/yum/sync.py", line 294, in run
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)     self.update_content(metadata_files, url)
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)   File "/usr/lib/python2.7/site-packages/pulp_rpm/plugins/importers/yum/sync.py", line 606, in update_content
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)     rpms_to_download, drpms_to_download = self._decide_what_to_download(metadata_files, catalog)
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)   File "/usr/lib/python2.7/site-packages/pulp_rpm/plugins/importers/yum/sync.py", line 645, in _decide_what_to_download
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)     self._decide_rpms_to_download(metadata_files, catalog)
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)   File "/usr/lib/python2.7/site-packages/pulp_rpm/plugins/importers/yum/sync.py", line 682, in _decide_rpms_to_download
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)     wanted, primary_rpm_count = self._identify_wanted_versions(package_info_generator)
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)   File "/usr/lib/python2.7/site-packages/pulp_rpm/plugins/importers/yum/sync.py", line 1105, in _identify_wanted_versions
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)     for model in package_info_generator:
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)   File "/usr/lib/python2.7/site-packages/pulp_rpm/plugins/importers/yum/repomd/packages.py", line 48, in package_list_generator
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)     root_element = xml_iterator.next()[1]
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848)   File "<string>", line 107, in next
Dec 10 07:55:59 foreman pulp: pulp_rpm.plugins.importers.yum.sync:ERROR: [79952a84] (51257-66848) ParseError: no element found: line 1, column 0
Dec 10 07:55:59 foreman pulp: pulp.server.async.tasks:INFO: [79952a84] Task failed : [79952a84-1880-4972-aef8-8d4aef0e1367]