bpo-36104 has been marked as a duplicate of this issue. Copy of Lukasz's msg336511:

The ARMv7 Ubuntu buildbot is consistently failing since build #2160:
https://buildbot.python.org/all/#/builders/106/builds/2160


This looks like a testing environment issue to me rather than a code issue. But I'd like it fixed either way before we get to 3.8.0 beta1 since this is a stable builder. Greg, you can ask Inadasan about whether his dict/OrderedDict changes might have any effect on this failure:
https://github.com/python/cpython/commit/c95404ff65dab1469dcd1dfec58ba54a8e7e7b3a

That was the only relevant change I observed between the working and the broken build.


The NNTP test failure looks like this:

======================================================================
ERROR: setUpClass (test.test_nntplib.NetworkedNNTP_SSLTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/test_nntplib.py", line 295, in setUpClass
    cls.server = cls.NNTP_CLASS(cls.NNTP_HOST, timeout=TIMEOUT,
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/nntplib.py", line 1077, in __init__
    self.sock = _encrypt_on(self.sock, ssl_context, host)
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/nntplib.py", line 292, in _encrypt_on
    return context.wrap_socket(sock, server_hostname=hostname)
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/ssl.py", line 405, in wrap_socket
    return self.sslsocket_class._create(
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/ssl.py", line 853, in _create
    self.do_handshake()
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/ssl.py", line 1117, in do_handshake
    self._sslobj.do_handshake()
ssl.SSLError: [SSL: DH_KEY_TOO_SMALL] dh key too small (_ssl.c:1055)



The HTTP test failure looks like this:

======================================================================
ERROR: test_networked_good_cert (test.test_httplib.HTTPSTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/test/test_httplib.py", line 1629, in test_networked_good_cert
    h.request('GET', '/')
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/http/client.py", line 1229, in request
    self._send_request(method, url, body, headers, encode_chunked)
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/http/client.py", line 1275, in _send_request
    self.endheaders(body, encode_chunked=encode_chunked)
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/http/client.py", line 1224, in endheaders
    self._send_output(message_body, encode_chunked=encode_chunked)
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/http/client.py", line 1016, in _send_output
    self.send(msg)
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/http/client.py", line 956, in send
    self.connect()
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/http/client.py", line 1391, in connect
    self.sock = self._context.wrap_socket(self.sock,
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/ssl.py", line 405, in wrap_socket
    return self.sslsocket_class._create(
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/ssl.py", line 853, in _create
    self.do_handshake()
  File "/ssd/buildbot/buildarea/3.x.gps-ubuntu-exynos5-armv7l/build/Lib/ssl.py", line 1117, in do_handshake
    self._sslobj.do_handshake()
ssl.SSLCertVerificationError: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: EE certificate key too weak (_ssl.c:1055)