[Satellite 6] Publishing new version of content view fails with error "ProxyAPI::ProxyException: ERF12-4115 [ProxyAPI::ProxyException]"

Issue

• Publishing new version of content view fails with error as below,

ProxyAPI::ProxyException: ERF12-4115 [ProxyAPI::ProxyException]: Unable to get classes from Puppet for puppet-environment-name ([RestClient::NotAcceptable]: 406 Not Acceptable) for proxy https://satellite.example.com:9090/puppet

ProxyAPI::ProxyException: ERF12-4115 [ProxyAPI::ProxyException]: Unable to get classes from Puppet for puppet-environment-name ([RestClient::Forbidden]: 403 Forbidden) for proxy https://satellite.example.com:9090/puppet"

"ProxyAPI::ProxyException: ERF12-4115 [ProxyAPI::ProxyException]: Unable to get classes from Puppet for puppet-environment-name ([Errno::ECONNREFUSED]: Connection refused - connect(2)) for proxy https://satellite.example.com:9090/puppet"

ProxyAPI::ProxyException: ERF12-2749 
 [ProxyAPI::ProxyException]: Unable to get environments from Puppet
 ([OpenSSL::SSL::SSLError]: SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verif...) for proxy https://satellite.example.com:9090/puppet

ERF12-4115 [ProxyAPI::ProxyException]: Unable to get environments from for puppet-environment-name ([OpenSSL::SSL::SSLError]: SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verif...) for proxy https://satellite.example.com:9090/puppet

ERF12-4115 [ProxyAPI::ProxyException]: Unable to get environments from Puppet puppet-environment-name ([OpenSSL::SSL::SSLError]: hostname does not match the server certificate) for Proxy https://satellite.example.com:9090/puppet  

• Looking in /var/log/foreman-proxy/proxy.log it shows,

ERROR -- : Failed to show puppet classes: Failed to query Puppet find environments API (503): This website is under heavy load
We're sorry, too many people are accessing this website at the same time. We're working on this problem. Please try again later.
ip-address - - [07/Jan/2016 16:49:35] "GET /puppet/environments/puppet-environment-name/classes HTTP/1.1" 406 259 0.3676

OR

ERROR -- : Failed to show puppet classes: Permission denied - /etc/puppet/modules/cis/manifests/init.pp
ip-address - - [07/Oct/2015 09:01:45] "GET /puppet/environments/puppet-environment-name/classes HTTP/1.1" 406 92 0.4038