Forward all TLD requests to another server

Solution 1:

For HTTP that might work, but for HTTPS the server might not have the right certificates, and for other protocols (such as for email) the HTTP service won't do the job.

Maybe stand up HAProxy in tcp mode, listening on the ports that connections come in on and proxying to the correct ports on the "real" server? This might not work quite right for some services, as the apparent source of the connection will be the HAProxy box.

A better approach might be to get access to the DNS. There must be some mechanism you can use to gain access to the account; is nobody else at the client's company set up as a contact with the DNS provider? Or can you just reset the guy's email password and then fire a password reset email?

Edit:

To get HAProxy working for this case, you'll want to install HAProxy - this requires EPEL to be enabled, if it's not already. Then yum install haproxy.

Edit /etc/haproxy/haproxy.cfg; not sure what exactly the default config looks like in there, but you'll want to clear out any listen sections first, while leaving the global and defaults sections.

Then, for each listening port that you need to send to the other server, you will want a section like this (note that if you add port 80, you'll need to stop the nginx service first):

listen port-443
    bind :443
    mode tcp
    balance roundrobin
    server realserver 192.0.2.1:443

(where 192.0.2.1 is the IP of the server that should be handling the connection).

Solution 2:

Another approach would be to just call the DNS Service provider, and explain them what happened. I guess after some "proof" that you're the owner of the domain / delegate or something, they might give you access or change it for you...