cdn-sync fails with "Error Cannot retrieve repository metadata (repomd.xml)" in Red Hat Satellite 5.8.

Issue

• After upgrading Red Hat Satellite to 5.8 cdn-sync fails with below error.

  # cdn-sync
  .
  15:41:18 ======================================
  15:41:18 | Channel: rhel-x86_64-server-optional-6
  15:41:18 ======================================
  15:41:18 Sync of channel started.
  15:41:18 Repo URL: https://cdn.redhat.com/content/dist/rhel/server/6/6Server/x86_64/optional/os
  15:41:18 ERROR: Cannot retrieve repository metadata (repomd.xml) for repository: rhel-6-server-optional-rpms__6Server__x86_64. Please verify its path and try again
  15:41:37 Sync of channel completed in 0:00:19.
  15:41:37 ======================================
  15:41:37 | Channel: rhel-x86_64-server-optional-7
  15:41:37 ======================================
  15:41:37 Sync of channel started.
  15:41:37 Repo URL: https://cdn.redhat.com/content/dist/rhel/server/7/7Server/x86_64/optional/os
  15:41:38 ERROR: Cannot retrieve repository metadata (repomd.xml) for repository: rhel-7-server-optional-rpms__7Server__x86_64. Please verify its path and try again
  15:41:48 Sync of channel completed in 0:00:10.
  

• Syncing single repo fails ;

  # cdn-sync -c rhel-x86_64-server-5-els
  08:28:58 ======================================
  08:28:58 | Channel: rhel-x86_64-server-5-els
  08:28:58 ======================================
  08:28:58 Sync of channel started.
  08:28:59 Repo URL: https://cdn.redhat.com/content/els/rhel/server/5/5Server/x86_64/os
  08:29:00 ERROR: Cannot retrieve repository metadata (repomd.xml) for repository: rhel-5-server-els-rpms__x86_64. Please verify its path and try again
  08:29:31 Sync of channel completed in 0:00:31.
  08:29:31 Total time: 0:00:31
  Problems occurred during syncing channel rhel-x86_64-server-5-els. Please check /var/log/rhn/cdnsync/rhel-x86_64-server-5-els.log for the details
  
  # cat /var/log/rhn/cdnsync/rhel-x86_64-server-5-els.log
  2017/08/05 07:36:44 +11:00 Command: ['/usr/bin/cdn-sync', '-c', 'rhel-x86_64-server-5-els']
  2017/08/05 07:36:44 +11:00 Sync of channel started.
  2017/08/05 07:36:45 +11:00 Repo URL: https://cdn.redhat.com/content/els/rhel/server/5/5Server/x86_64/os
  2017/08/05 07:36:45 +11:00 #1.1 GSS_MARK FAILED REPOMD for channel ['https://cdn.redhat.com/content/els/rhel/server/5/5Server/x86_64/os/']
  2017/08/05 07:36:45 +11:00 #2.1 GSS_MARK FAILED REPOMD for channel ['https://cdn.redhat.com/content/els/rhel/server/5/5Server/x86_64/os/']
  2017/08/05 07:36:46 +11:00 ERROR: Cannot retrieve repository metadata (repomd.xml) for repository: rhel-5-server-els-rpms__x86_64. Please verify its path and try again
  2017/08/05 07:36:46 +11:00 ERROR: Cannot retrieve repository metadata (repomd.xml) for repository: rhel-5-server-els-rpms__x86_64. Please verify its path and try again