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Same Domain, Multiple Machines, SSL?

I saw a lot of misinformation about this on the inter-tubes recently, some of it intentional misleading of customers, some of it unintentional, so it might be remedial for a lot of readers but posting a clarification here because its worth it to help clear up the confusion. Here are some facts that should help people when first making the leap to securing multiple server environments:

Servers are domain and private key specific. They are not machine specific. You are welcome to generate multiple SSL certificates for the same domain to host on separate servers. Think for a bit, this *has* to be true. When everyone goes to, are they hitting the same web server or SSL caching server? Of course not.*

The most common scenario where this would be valuable is with a load balanced web cluster, but I recently came across this in a deployment with web and mail component where the mail admin neglected to give their MTA a unique FQDN *and* the organization is using SSL/TLS for mail retrieval *and* the organization does not wish to use a self-signed certificate to this end.

You dont need to purchase multiple certificates to this end. Just export the certificate to a PFX and import it to the next server. In IIS6, this process is outlined here: To use OpenSSL in Linux, here is a good guide: :

 (*Yeah I know they are using hardware acceleration, smarty pants. Same argument applies, plus complexity of dealing with hardware tokens)