NOTE: Puppet Enterprise is not supported to be installed on the same host as Satellite 6. This bug is to document the workaround in case this situation occurs.

If a user has Puppet Enterprise installed on Satellite 6 in conjunction with Puppet 3/4/5 installed from Satellite 6 there may be an error during the execution of:

satellite-installer --upgrade
...
stderr: stty: standard input: Inappropriate ioctl for device
/usr/share/ruby/vendor_ruby/puppet/vendor/safe_yaml/lib/safe_yaml.rb:188:in `initialize': No such file or directory - /opt/puppetlabs/puppet/cache/foreman_cache_data/candlepin_db_password (Errno::ENOENT)

The issue comes from the fact that Puppet Enterprise installs files in 
/opt/puppetlabs/bin/puppet then that will be used by the installer. 

Puppet can't distinguish between PE and Puppet 4 because they are packaged in
the same way. Also note that if PE packages are Puppet 5 then it will
fail because we miss 2 patches in the installer.

Beware that satellite-installer --upgrade-puppet will probably behave in
unexpected ways and it's recommended to do this manually.
hooks/init/31-upgrade-puppet.rb should be very readable.

WORKAROUND:

1) move the cache from /var/lib/puppet/foreman_cache_data to /opt/puppetlabs/puppet/cache/ 

2) place a symlink in /var/lib/puppet to  /opt/puppetlabs/puppet/cache/ 

3) re-run satellite-installer --upgrade