[Satellite 6] RHEL 5 client systems puppet agent fails to start / register correctly with "Exiting; no certificate found and wait for cert is disabled" "Error: unknown message digest algorithm"

Issue

• When using a Satellite 6 server deployed on RHEL 7 OS, attempts to register the puppet agent on a RHEL5 system with the puppet master on Satellite 6 (either in kickstart %post install or via the command line at a later time) the puppet agent will fail to start and register correctly, you are left with:

# /usr/bin/puppet agent -v --config /etc/puppet/puppet.conf -o --tags no_such_tag --server <serverfqdn> --no-daemonize
Exiting; no certificate found and waitforcert is disabled

On the Puppet master if you try and sign it manually you get:

# puppet cert sign --digest SHA1 <serverfqdn>
Error: unknown message digest algorithm