Q: Apache2/Ubuntu 14.04 error.log Hostname provided via SNI and hostname provided via HTTP are different In my apache2 error.log I see every few minutes an error message "Hostname … provided via SNI and hostname www.google.com.hk provided via HTTP are different".
In the access.log each error can be often be connected to a HEAD-request.
We have these errors on several Google Cloud instances. All Ubuntu 14.04 with Apache2.4.
Below some errors and joined access log-info.
Any idea how we can prevent errors like these with our server configuration?
Or are those client-errors and it's okay apache logs them?
Or can we filter those errors so they do not added to the error.log file?
Regards, Eric
[Tue Sep 22 00:05:05.427193 2015] [ssl:error] [pid 30172] AH02032: Hostname ?18880 provided via SNI and hostname www.google.com.hk provided via HTTP are different
171.118.181.162 - - [22/Sep/2015:00:05:05 +0200] "HEAD /search?q=g HTTP/1.1" 400 5568 "-" "-"

[Tue Sep 22 00:23:28.422609 2015] [ssl:error] [pid 31700] AH02032: Hostname ?20939 provided via SNI and hostname www.google.com.hk provided via HTTP are different
183.15.28.236 - - [22/Sep/2015:00:23:28 +0200] "HEAD /search?q=g HTTP/1.1" 400 6096 "-" "-"

[Tue Sep 22 01:58:09.291321 2015] [ssl:error] [pid 7844] AH02032: Hostname 130.211.51.211 provided via SNI and hostname www.dotcube.us provided via HTTP are different
52.89.122.174 - - [22/Sep/2015:01:58:09 +0200] "GET / HTTP/1.1" 400 6656 "-" "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; InfoPath.2)"

[Tue Sep 22 03:50:19.937589 2015] [ssl:error] [pid 16136] AH02032: Hostname ?730 provided via SNI and hostname www.google.com.hk provided via HTTP are different
210.13.97.168 - - [22/Sep/2015:03:50:19 +0200] "HEAD /search?q=g HTTP/1.1" 400 5917 "-" "-"


A: They're client misconfiguration errors -- or, more likely, someone trying to be "clever", given how weird the SNI hostnames are.  I'm not aware of any way to filter out just those errors without possibly catching other things in the net, too.
