Generate a custom Diffie-Hellman parameter file

The "Logjam Attack" (CVE-2015-4000) exposed several weaknesses in the Diffie-Hellman (DH) key exchange. To help mitigate the "Logjam Attack," PE ships with a pre-generated 2048 bit Diffie-Hellman param file. In the case that you don't want to use the default DH param file, you can generate your own.

Note: In the following procedure, <PROXY-CUSTOM-dhparam>.pem can be replaced with any file name, except dhparam_puppetproxy.pem, as this is the default file name used by PE.

On your primary server, run:
```
/opt/puppetlabs/puppet/bin/openssl dhparam -out /etc/puppetlabs/nginx/<PROXY-CUSTOM-dhparam>.pem 2048
```
Note: After running this command, PE can take several minutes to complete this step.
Open your pe.conf file (located at /etc/puppetlabs/enterprise/conf.d/pe.conf) and add the following parameter and value:
```
"puppet_enterprise::profile::console::proxy::dhparam_file": "/etc/puppetlabs/nginx/<PROXY-CUSTOM-dhparam>.pem"
```
Run Puppet: puppet agent -t.