The expireAtLastByte option enables the integrated cache to expire the object as soon as it has been downloaded. Only requests that are outstanding requests at that time are served from cache. any new requests are sent to the server. This setting is useful when the object is frequently modified, as in the case of stock quotes. This expiry mechanism works along with the Flash Cache feature. To configure expireAtLastByte option, run the following command from the command line interface:
add cache contentGroup <Group_Name> –expireAtLastByte YES
In the output, check the value of the Memory usage limit parameter. This is the maximum memory allocated for cache.
In the output, check the values of the Memory usage and Memory usage limit parameters indicating the memory used and allocated for the individual content group.
For any model of the NetScaler appliance, you can allocate half of the memory to the cache. However, Citrix recommends allocating a little less than half of the memory, because of internal memory dependency. You can run the following command to allocate 1 GB of memory to cache:
set cache parameter -memLimit 1024
To display the summary of the cache statistics.
To display the full details of the cache statistics.
If the object stored in the cache is, for example, GET //10.102.12.16:80/index.html, you can display the details about the object by running the following command from the command line interface of the appliance:
show cache object -url '/index.html' -host 10.102.3.96 -port 80
add cache policy p2 -rule ns_url_path_cgibin -action CACHE –storeInGroup g1 add cache policy p1 -rule ns_url_path_cgibin -action CACHE -storeInGroup g2
In this case, for the multiple requests, if policy p1 is evaluated, its hit counter is incremented and the policy stores the object in the g1 group, which has hit parameters. Therefore, you have to run the following command to display the objects from the cache:
show cache object -url "/cgi-bin/setCookie.pl" -host 10.102.18.152 groupName g1
Similarly, for another set of multiple requests, if policy p2 is evaluated, its hit counter is incremented and the policy stores the object in the g2 group, which does not have hit parameters. Therefore, you have to run the following command to display the objects from the cache:
show cache object -url "/cgi-bin/setCookie2.pl" -host 10.102.18.152
root@ns# /netscaler/nscachemgr -a //10.102.3.89:80/image8.gif //10.102.3.97:80/staticdynamic.html //10.102.3.97:80/ //10.102.3.89:80/image1.gif //10.102.3.89:80/file5.html //10.102.3.96:80/ //10.102.3.97:80/bg_logo_segue.gif //10.102.3.89:80/file500.html //10.102.3.92:80/ //10.102.3.96:80/cgi-bin/rfc/ccProxyReval.pl Total URLs in IC = 10The blank entries in the output are due to the default caching properties for GET / HTTP/1.1.
For responses served from the integrated cache, the server log field contains the value IC. For responses served from a server, the server log field contains the value sent by the server. Following is a sample log entry for an integrated caching transaction:
"10.102.1.52 - "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 4.0; .NET CLR 1.0.3705)" "GET /" 200 0 "IC" 10.102.1.45"
Along with a client request, the response logged is the one sent to the client and not necessarily the one sent by the server.
How do we select a hitparam? POST /data2html.asp?param1=value1¶m2=¶m3¶m4=value4 HTTP/1.1 Accept: image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/vnd.ms-powerpoint, application/vnd.ms-excel, application/msword, application/x-shockwave-flash, */* Referer: http://10.102.3.97/forms.html Accept-Language: en-us Content-Type: application/x-www-form-urlencoded Accept-Encoding: gzip, deflate User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1) Host: 10.102.3.97 Content-Length: 153 Connection: Keep-Alive Cache-Control: no-cache Cookie: ASPSESSIONIDQGQGGRNY=NNLLKDADEENOAFLCCDGFGDMO S1=This+text+is+only+text%2C+not+more+and+not+less%2C+%0D%0Ajust+text+to+be+itself%2C+namely+%22Text%22+to+be+posted+as+text+%28what+else...%29&B1=SubmitIn the above request, you can use S1 and B1, highlighted in bold face for your reference, as hitParams depending on your requirements. Additionally, if you use -matchCookies YES in the ASPSESSIONIDQGQGGRNY content group, then you can also use these parameters as hitParams.
No. You cannot enable PET and Flash Cache on the same content group. The integrated cache does not perform AutoPET function on Flash Cache content groups. The PET feature ensures that the integrated cache does not serve a stored object without consulting the server. You can configure PET explicitly for a content group.
This ignores the destination IP address.
This matches the destination IP address.
This uses the DNS server.
This completely depends on your configuration. By default, 404 responses are cached for 10 minutes. If you want all 404 responses to be fetched form the server, specify–weakNegRelExpiry 0. You can fine tune the –weakNegRelExpiry to a desired value, such as higher or lower to get the 404 responses cached appropriately. If you have configured –absExpiry for positive responses, then it might not yield desired results.
The Microsoft Internet Explorer browser might be taking the content from its local cache instead of the NetScaler integrated cache. The reason could be that the Microsoft Internet Explorer browser is not respecting the expiry related header in the response.
To resolve this issue, you can disable the local cache of the Internet Explorer and clear the offline content. After clearing the offline content, the browser should display the updated content
Check to see if the server time and NS time are in sync. And the weakPosrelexpiry limit set should bear the time difference between NS and server as shown below
Tue May 15 18:53:52 IST 2012