Cache file size of “Cache on device RAM with overflow on hard disk” is growing faster than “Cache on device hard disk”

  • Cache Type = “Cache on device hard disk”

The block reservation of “Cache on device hard disk” is ONLY 4KB, and it’s random I/O.

  • Cache Type = “Cache on device RAM with overflow on hard disk”

Since “overflow on hard disk” is vhdx format, the block reservation is 2MB & required for sequential I/O, which will provide better performance than legacy local write cache, but it will consume more filesystem usage.

Hence if there’s heavy IOPS occurred on target device, and RAM cache is running out of range, “overflow on hard disk” cache will be generated, which may grow very fast.

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  • No Related Posts

Error “No Apps available at this time” on workspace for iOS app after upgrading to ADC 13.0 build 52.24

Version 13.0 build 52.24 do not set pwcount cookie in response to /vpn/index.html request as below.

HTTP/1.1 200 OK

Date: Fri, 08 May 2020 05:19:10 GMT

Server: Apache

X-Frame-Options: SAMEORIGIN

Last-Modified: Fri, 08 May 2020 04:56:44 GMT

Accept-Ranges: bytes

Content-Length: 3674

Cache-Control: no-cache, no-store, must-revalidate

Pragma: no-cache

Expires: 0

Keep-Alive: timeout=15, max=92

Connection: Keep-Alive

Content-Type: text/html; charset=UTF-8

Set-Cookie: pwcount=0;Secure;HttpOnly;Path=/;expires=Wednesday, 09-Nov-1999 23:12:40 GMT

Cache-Control: no-cache

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Is ADC impacted by CVE-2020-10110, CVE-2020-10111 and CVE-2020-10112

Is ADC vulnerable to these CVEs recently discovered ?.

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-10110

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-10111

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-10112

No, ADC is not impacted by these CVEs

CVE-2020-10110

There is no sensitive information disclosure through the cache headers on Citrix ADC. The “Via” header lists cache protocols and recipients between the start and end points for a request or a response. The “Age” header provides the age of the cached response in seconds. Both headers are commonly used for proxy cache and the information is not sensitive.

https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Age

https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Via

CVE-2020-10111

Citrix ADC only caches HTTP/1.1 traffic for performance optimization. In conjunction with the response for CVE-2020-10112, the reported behavior is not considered a security issue.

CVE-2020-10112

By default, Citrix ADC only caches static content served under certain URL paths for Citrix Gateway usage. No dynamic content is served under these paths, which means those cached pages would not change based on parameter values. All other data traffic going through Citrix Gateway are NOT cached by default.

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ShareFile Drive Mapper is slow to load

If experiencing slowness in Drive Mapper, try increasing the cache size to which Drive Mapper has access. You can do this by navigating to your system tray hidden icons, right-clicking the Drive Mapper application, choosing Settings, and increasing the cache size.

Drive Mapper is an API driven tool that only caches local data, and the files seen in the directory are often not actually housed on your local computer. Many users sometimes fail to understand that actions they perform will not be as responsive as in other areas of the File Explorer, seeing as how they are dependent on network activity. Frequent directory changes and working with larger/numerous files will affect how the program functions.

The application is fastest when you are navigating among common drives, the size of data which is less than the cache setting. When you exceed that setting, Drive Mapper has to dump data to make room for more data, and files or folders that you were using and accessing very quickly are now much slower, as the application has to re-download the associated files. Having an increased cache will help you keep more data on the machine and improves performance.

Regularly restarting the affected computer on at least a daily basis, and verifying the version of software installed is the most current, are recommended.

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Symantec Endpoint Protection Manager database Slow Issue

I need a solution

Hi,

Recently we are having issue with SEPM portal slowness.

we have done root cause analysis and we have find that we have enought 16GB of memory on windows server but Symantec Embedad Database using only 550MB. As per symantec guide line we have access database and we have check that maxcachsize is configured as 512MB. we have check with following command select property(‘MaxCacheSize’);

But we are searching for the resolution that can upgrade the cache size.

Please help to resolve this issue.

Thanks

Shivang  

0

Related:

How to Resolve Browser Related Issues When Using ShareFile

Your browser cache stores temporary information to speed up web browsing. Whenever you encounter a problem with the ShareFile web app, we highly recommend clearing your browser cache to eliminate any potential problems that may arise from cached versions of web pages, including stored settings.

ShareFile recommends clearing your cache when:

  • Preview fails or is otherwise broken / generating an error
  • Page fails to load
  • Cannot access certain menu in settings section of your account
  • Changes to account settings not taking effect immediately after adjusting them
  • Other application discrepancies not mentioned in this article

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Citrix ADC Integrated Caching Counters

This article contains information about the newnslog Integrated Caching counters and a brief description of the counters.

Using the Counters

Log on to the ADC using an SSH client, change to SHELL, navigate to the /var/nslog directory, and then use the ‘nsconmsg’ command to see comprehensive statistics using the different counters available. For the detailed procedure refer to Citrix Blog – NetScaler ‘Counters’ Grab-Bag!.

The newnslog Integrated Caching counters

The following table lists the different newnslog Integrated Caching counters and a brief description of the counter.

newnslog Counter

Description

cac_tot_req

Total cache hits plus the total cache misses.

cac_cur_pcb_hit

This number should be close to the number of hits being served currently.

cac_tot_non304_hit

Total number of full (non-304) responses served from the cache. A 304 status code indicates that a response has not been modified since the last time it was served.

cac_tot_304_hit

Object not modified responses served from the cache.

(Status code 304 served instead of the full response.)

cache_tot_hits

Responses served from the integrated cache. These responses match a policy with a CACHE action.

cache_percent_304_hits

304 responses as a percentage of all responses that the NetScaler appliance served.

cache_percent_hits

Cache hits as percentage of the total number of requests.

cache_recent_percent_304_hits

Recently recorded ratio of 304 hits to all hits expressed as percentage

cache_recent_percent_hit

Recently recorded cache hit ratio expressed as percentage.

cac_cur_pcb_miss

Responses fetched from the origin and served from the cache. Should approximate storable misses. Does not include non-storable misses.

cache_tot_misses

Intercepted HTTP requests requiring fetches from origin server.

cache_tot_storable_misses

Cache misses for which the fetched response is stored in the cache before serving it to the client. Storable misses conform to a built-in or user-defined caching policy that contains a CACHE action.

cache_tot_non_storable_misses

Cache misses for which the fetched response is not stored in the cache. These responses match policies with a NOCACHE action or are affected by Poll Every Time.

cache_tot_revalidation_misses

Responses that an intervening cache revalidated with the integrated cache before serving, as determined by a Cache-Control: Max-Age header configurable in the integrated cache.

cache_tot_full_to_conditional_request

Number of user-agent requests for a cached Poll Every Time (PET) response that were sent to the origin server as conditional requests.

cache_percent_storable_miss

Responses that were fetched from the origin, stored in the cache, and then served to the client, as a percentage of all cache misses.

cache_recent_percent_storable_miss

Recently recorded ratio of storable misses to all misses expressed as percentage.

cache_percent_successful_reval

Percentage of times stored content was successfully revalidated by a 304 (Object Not Modified) response rather than by a full response

cache_recent_percent_successful

_reval

Recently recorded percentage of times stored content was successfully revalidated by a 304 response rather than by a full response

cache_tot_successful_revalidation

Total number of times stored content was successfully revalidated by a 304 Not Modified response from the origin.

cache_percent_byte_hit

Bytes served from the cache divided by total bytes served to the client. If compression is On in the NetScaler, this ratio might not reflect the bytes served by the compression module. If the compression is Off, this ratio is the same as cachePercentOriginBandwidthSaved.

cache_recent_percent_byte_hit

Recently recorded cache byte hit ratio expressed as percentage. Here we define byte hit ratio as ((number of bytes served from the cache)/(total number of bytes served to the client)). This is the standard definition of Byte Hit Ratio. If the compression is turned ON in the NetScaler appliance, then this ratio does not mean much. This might under or overestimate the origin-to-cache bandwidth saving depending upon whether bytes served by CMP in NetScaler are more or less than compressed bytes served from the cache. If CMP is turned OFF in the NetScaler appliance, then this ratio is the same as cacheRecentPercentOriginBandwidthSaved.

cactor_max32_res_so_far

Size, in bytes, of largest response sent to client from the cache or the origin server.

cache_tot_resp_bytes

Total number of HTTP response bytes served by the NetScaler appliance from both the origin and the cache.

cache_bytes_served

Total number of bytes served from the Integrated Cache.

cache_comp_bytes_served

Number of compressed bytes served from the cache.

cac_tot_parameterized_inval_req

Requests matching a policy with an invalidation (INVAL) action and a content group that uses an invalidation selector or parameters.

cac_tot_non_parameterized

_inval_req

Requests that match an invalidation policy where the invalid Groups parameter is configured and expires one or more content groups.

cac_tot_inval_nostore_miss

Requests that match an invalidation policy and result in expiration of specific cached responses or entire content groups.

cache_percent_origin_

bandwidth_saved

Percentage of origin bandwidth saved, expressed as number of bytes served from the integrated cache divided by all bytes served. The assumption is that all compression is done in the NetScaler appliance.

cache_recent_percent_origin

_bandwidth_saved

Bytes served from cache divided by total bytes served to client. This ratio can be greater than 1 because of the assumption that all compression has been done in the NetScaler appliance.

cactor_tot_expire_at_last_byte

Instances of content expiring immediately after receiving the last body byte due to the Expire at Last Byte setting for the content group.

cac_tot_enable_flashcache

Number of requests to a content group with flash cache enabled that were cache misses. Flash cache distributes the response to all the clients in a queue.

cac_tot_delayed_logging

Number of requests to a content group with flash cache enabled that were cache hits. The flash cache setting queues requests that arrive simultaneously and distributes the response to all the clients in the queue.

cac_tot_parameterized_non304_hit

Parameterized requests resulting in a full response (not status code 304: Object Not Updated) served from the cache.

cactor_tot_parameterized_req

Total number of requests where the content group has hit and invalidation parameters or selectors.

cac_tot_parameterized_304_hit

Parameterized requests resulting in an object not modified (status code 304) response.

cache_tot_parameterized_hits

Parameterized requests resulting in either a 304 or non-304 hit.

cache_percent_parameterized

_304_hits

Percentage of parameterized 304 hits relative to all parameterized hits.

cache_recent_percent_

parameterized_hits

Recently recorded ratio of parameterized 304 hits to all parameterized hits, expressed as a percentage

cactor_tot_pet_with_nostore_reval

Requests that triggered a search of a content group that has Poll Every Time (PET) enabled (always consult the origin server before serving cached data).

cache_tot_pet_hits

Number of times a cache hit was found during a search of a content group that has Poll Every Time enabled.

cache_percent_pet_hits

Percentage of cache hits in content groups that have Poll Every Time enabled, relative to all searches of content groups with Poll Every Time enabled.

cache_max_mem

Largest amount of memory the NetScaler appliance can dedicate to caching, up to 50% of available memory. A 0 value disables caching, but the caching module continues to run.

cache64_max_mem

Largest amount of memory the NetScaler appliance can dedicate to caching, up to 50% of the available memory. A 0 value disables caching, but the caching module continues to run.

cache_max_mem_active

Currently active value of maximum memory.

cache_utilized_mem

Amount of memory the integrated cache is currently using.

cactor_cur_hash

Responses currently in integrated cache. Includes responses fully downloaded, in the process of being downloaded, and expired or flushed but not yet removed.

cache_cur_marker_cell

Marker objects created when a response exceeds the maximum or minimum size for entries in its content group or has not yet received the minimum number of hits required for items in its content group.

cactor_err_no_buf

Total number of times the cache failed to allocate memory to store responses.

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