Is Apache sends "X-Cache:MISS" header even when caching is off (disable)?

[anukedari]

Hi,

Could any boby please help to get the answers for the following questions:

Is Apache always sends "X-Cache:MISS" header even when caching is off (disable)? or

Can we say that cache settings are enable if it sends "X-Cache:MISS" header in the response?

Your help would be appreciated.

Thanks
Anu

[Motoma]

You could try experimenting, however, I would not expect Apache to report any cache information if caching was not configured in the first place.

[anukedari]

You mean that the "X-Cache:MISS" header is the normal behaviour in Reponse even if the cache settings are disabled in Apache??

I assume cache settings are disabled in my Apache by seeing the following lines in httpd.conf

# To enable the cache as well, edit and uncomment the following lines:
# (no cacheing without CacheRoot)
#
# CacheRoot "/var/apache/proxy"
# CacheSize 5
# CacheGcInterval 4
# CacheMaxExpire 24
# CacheLastModifiedFactor 0.1
# CacheDefaultExpire 1
# NoCache a-domain.com another-domain.edu joes.garage-sale.com


Your help would be appreciated

[Motoma]

I am not sure what help you are looking for. Please elaborate on the issue you are having, as I am afraid your questions are not producing useful answers.

[anukedari]

Hi,

I think below information will give the clear picture.

Following is the request and response (I used SOAPUI for webservice request and response):


Request :-
POST http://ukdiscoverywstest.gsk.com/ChemicalHierarchy/services/ChemicalHierarchyServiceV1 HTTP/1.1
Content-Type: text/xml;charset=UTF-8
SOAPAction: "getServiceInfo"
User-Agent: Jakarta Commons-HttpClient/3.0.1
Host: ukdiscoverywstest.gsk.com
Proxy-Connection: Keep-Alive

Response:-
HTTP/1.1 200 OK
Date: Mon, 11 Jun 2007 15:14:53 GMT
Server: Apache-Coyote/1.1
X-Powered-By: Servlet 2.4; JBoss-4.0.2 (build: CVSTag=JBoss_4_0_2 date=200505022023)/Tomcat-5.5
Content-Type: text/xml;charset=utf-8
Via: 1.1 ukdiscoverywstest.gsk.com (Apache/1.3.31)
X-Cache: MISS from ukdiscoverywstest.gsk.com
Transfer-Encoding: chunked


its just that "Cache miss" makes me concerned that caching is actually still turned on. If you confirm that it always sends that header, even when caching is off, then I'd consider this problem is solved.

Thanks
Anu

[Motoma]

Why not just add a no-cache specifier in your request?
I believe the syntax is:

Pragma: no-cache

[anukedari]

Thanks for your interest.

In one of the servlet the following lines are hard coded

response.setContentType("text/xml; charset=utf-8");
response.setContentLength(translated.length());
response.setHeader("Expires", "Sat, 6 May 1995 12:00:00 GMT");
response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
response.addHeader("Cache-Control", "post-check=0, pre-check=0");
response.setHeader("Pragma", "no-cache");

Apache (Version: 1.3.31) is not allowed to add "Pragma:no-cache" in httpd.conf file.

Please let me know whether "X-Cache:MISS" is normal behaviour or abnormal?
What is the negative impact of this header?

[Motoma]

If you are sending Pragma: No-Cache in the request, you do not need to worry about receiving cached data.

[anukedari]

Many Thanks , Now I am bit relief.

Please let me know why "X-Cache:MISS" header comes even though Cache settings are disabled in Apache?