Hi, my existing setup is/was simple. Had a single site active directory for 30 users and an exchange server. I now have multiple windows 2008 severs split across multiple sites.
All computer workstation identification certs were pushed out via autoenrollment and as such they trust the root CA which was the one to issue the certificates.
As i will now have a number of sites i think it would be prudent to have subordinate CAs at each remote location to issue certificates there.
My question is, how would this affect the current computers having the existing CA where it is directly issued from the enterprise root, compared to other computers who were issued via the subordinate CA when i get them running? Im guessing not much, since all computers will trust the root anyway through thet certificate tree? Only down side is if the root got comprimised in this scenario since they would still trust it.
Given the site links are expanding, Is it possible to move my existing enterprise root CA to a standalone root CA, and then create multiple subordinate CAs to issue certs on the clients behalf? This would be the ideal setup as a managed upgrading process. Can i move the root enterprise CA to an offline root CA?
To aid my understanding, do enterprise root CA issue certificates to workstations by default? Im guessing not, since i had to create a workstation identification template for the enterprise root CA.
How could i ensure in future that the root CA only issues certificates for other subordinate CA's and NOT workstations? Would this be through the certificate management mmc console? Is this controlled by active directory GPO or some other setting?
What is the purpose of having an online root enterprise CA and subordinate enterprise CA? I cant see much benefit and indeedd maybe this is less secure as the root is online... this is fine for small networks but i have found may no longer be ideal for me. This is why i wish to move my existing root enterprise CA to an offline root standalone CA.
Can active directory automatically publish the revocation list to http for it to check? Do i need to have IIS running on the server? I see the url for revocation checking but when i type it in in my browser i get a blank page again i presume because IIS is not running. I did read that this CRL location can be changed without revoking any certificates, this will be updated when the client renews their certificate. http://episteme.arstechnica.com/eve/forums/a/tpc/f/12009443/m/405009001931/r/797005301931
So in summary, it would be great if i can install a subordinate CA into the system, then reissue new workstation certificates to all clients via that subordinate CA. I can then revoke the original certs issued directly by the root before i move it offline to ensure the clients will renew with the subordinate CA from that point on. This is a slightly painfull process as certs are already issued to clients and this is used to identify the exchange server in exchange 2007. But as long as the chain of trust isnt broken i dont see a problem with the above but thoughts would be very much appreciated.
Many thanks in advance,
Chris