How many domains can be bound with one SSL certificate?

iis ssl asp.net azure

9,720

Solution 1

There are multiple certificate types.

You can have a wildcard cert *.domain.com which is valid for all subdomains.
You can have a single-name cert host.domain.com which is only valid for this host
You can have a multi-name cert host1.domain1.com, host2.domain2.com, this is called a SAN (Subject Alternative Name) Certficiate. They are often called "UC-Certificate" by cert vendors.

I'm not sure where the technical limit is on a SAN cert, but it's certainly more than 10 names.

Solution 2

If they are truely unique domain names, you can get a SAN (Subject Alternative Name) certificate. Most vendors will let you put about 40 domain names on one cert. If they are sub-domains, a wildcard cert is the way to go. For each of tjose options you only need 1 ip as the cert is valid for all listed domain names.

9,720

mr3oh5

Updated on September 18, 2022

Comments

mr3oh5 over 1 year

Let say I have an ASP.NEt application which is bound with more than 10 domains using host headers. Is one certificate is enough for me? or I need more than 1 certificate for each domain? If I need 1 certificate, then adding a new domain means reinstall the certificate?
mr3oh5 almost 12 years

What if I needed to add a new domain in SAN? Is I need to reinstall this domain to server? Whether domain be added dynamically?
mr3oh5 almost 12 years

Just see the below comment.
MichelZ almost 12 years

On many cert vendors, you can add and remove SAN entries anytime, and re-issue the cert. This is however vendor specific.
Zypher almost 12 years

You will need to have the issuer re-issue the cert with the new name in addition to the ones already set up. Most vendors allow you to do this via a web portal. Then you'll need to re-install the cert
mr3oh5 almost 12 years

Is I need to reinstall the certificate? I mean I need to configure my server every time when I add a new domain.
MichelZ almost 12 years

Yes, with a SAN Certificate you have to. The only time where you don't have to would be a wildcard cert. Or maybe the SAN cert allows to use Wildcard, to cover multiple domains, not sure (i.e. *.domain1.com & *.domain2.com