Due to the SSL specification it is _IMPOSSIBLE_ to have more than one certificate on a given ip:port pair. Why? Because the certificate has to be sent immediately after a connection to the ip:port pair _BEFORE_ the client sends information about _which_ website it intends to contact (thus the server has no way to know which certificate, if many sites are hosted on a given ip:port pair, to supply and must choose ONE). As such virtual nameservers and https are impossible to get working with different certificates.
However, there are some solutions:
a) get more IP's and host each https site on a different IP
b) use different port numbers on the same IP
BOTH a and b allow different certificates per site, since they use different host:ip pairs
c) use a single wildcard certificate or a certificate for more than one site. Basically a single certificate which is valid for both abc.com and def.com. Searching around on Google should reveal a wiki with more information about how to do this and remain compatible with the major web browsers (I think the link should also be in the CentOS list archives).
It should be noted that solution (b) is impractical, many places allow https traffic only on the default https/443 port.
Solution (a) is feasible and easy, however requires extra public IPs and will likely increase hosting costs.
Solution (c) is the cheapest, however I've yet to try implementing it.
[Further note: it is possible to run https over http on port 80 with transparent upgrade, but most web browsers and proxies don't support this and as such this is also not a viable solution...]
Cheers, MaZe.
On Sat, 18 Mar 2006, Ara Avvali wrote:
Good afternoon everyone,
This is my first post here. I was wondering if someone could clear my mind about this.
I have a dedicated server with a single ip address assigned to it. I want to host couple of site which are hosted somewhere else and they have signed certificates. Now I want to host them all on this single server.
Is it possible to bound more than one cert to a single IP based apache server and host multiple virtual directories?
I did a research on line and found couple answers which are all confusing me.
One suggested that I need to get additional ip's and assign different sites to it. (Not a very practical solution)
Other one says we can use the same cert and ip but have secondary host on different port number than default. Something likes https://www.abc.com https://www.abc.com/ and https://www.def.com:444 https://www.def.com:444/ and so on. But this will cause people a warning regarding the certificate error on second path, is that correct?
Some one suggested a wild card certificate but how can I do that since dedicated server name is a.dedicated.hostingcompany.com and I need to generate certificates covering *.abc.com and *.def.com
Would someone kindly clear my mind on this issue?