Performance penalty when using regular expressions in server_name?

Server NGINX
1

Hi,

let assume that we run the following domains:

Our main site should be www.a-good-example.com – people coming from any
other mentioned domain/combination should be redirected to the main
site.

I could now write a single server block like

server {
// …
server_name ~^(?:www.)?a[-]?good-example.(?:org|net)$
~^ a[-]?good-example.com $;

 rewrite ^ $scheme://www.a-good-example.com $request_uri permanent;

}

I am using regular expressions as server_name values, I think you get
the
point.

I could also avoid regular expressions:

server {
// …
server_name agoodexample.org
a-good-example.org
www.agoodexample.org
www.a-good-example.org
agoodexample.net
a-good-example.net
www.agoodexample.net
www.a-good-example.net
agoodexample.com
www.agoodexample.com
a-good-example.com;

 rewrite ^ $scheme://www.a-good-example.com $request_uri permanent;

}

Q1: Are both configurations equal or is there any performance
difference?
E.g. would you recommend one configuration more than the other?

Q2: When using regular expressions in server_name, the regular
expression
will also appear in the error_log. Is it possible to see the actual
name instead the expression in the log?

I am using nginx-1.4.x with pcre-jit enabled.

Thanks.

–
Regards,
Igor

2

A different way would to use Lua and an alias table, for a dynamic site
I
use this to allow a site multiple aliases all directing to the same
root,
its a simple array with 2 lines for each main site, 1 as server_name and
line 2 endless aliases. Its fast and no need to edit nginx.conf just
edit a
plain ascii file.

Posted at Nginx Forum:

3

On Jan 29, 2014, at 23:52 , Igor Sverkos wrote:

rewrite ^ $scheme://www.a-good-example.com $request_uri permanent;
        a-good-example.org
rewrite ^ $scheme://www.a-good-example.com $request_uri permanent;

}

Q1: Are both configurations equal or is there any performance difference?
E.g. would you recommend one configuration more than the other?

The second is faster but I believe performance is negligible.
And it’s better to use

return 301 $scheme://www.a-good-example.com/$request_uri;

Q2: When using regular expressions in server_name, the regular expression
will also appear in the error_log. Is it possible to see the actual
name instead the expression in the log?

I am using nginx-1.4.x with pcre-jit enabled.

$host.

–
Igor S.