Using NCache Session State Store Provider

NCache Session State Provider is a custom SessionStateStoreProviderBase implementation for an ASP.NET application.

How to Configure NCache Session State Provider

Modify Assemblies Tag

Modify <assemblies> section in the application's web.config and add following assembly.

For Enterprise and Professional Editions:-

</assemblies>

For Open Source Edition:-

</assemblies>

Replace version "x.x.x.x" with the actual NCache version that you have.
Refer Alachisoft.NCache.SessionStoreProvider in your project from "$NCache-install/bin/assembly/[2.0 or 4.0] folder.

Modify sessionState Tag

Edit your application's web.config file and modify the <sessionState> section as given below. Place the following code under <system.web> tag.

</providers>

</sessionState>

Following is the description of different key-value pairs specified above:

Member	Description
sessionAppId	Optional string attribute. Specifies an identifier to make sure that session ID remains unique in case multiple applications are using the same cache. Application ID should be the same for an application in a web farm. If no app ID is specified, nothing will be concatenated with session ID.
cacheName	Required string attribute. Specifies the name of the cache to be used for caching session. If no cache name is specified, a configuration exception will be thrown.
enableSessionLocking	Optional Boolean attribute. If this flag is set, NCache Session Store Provider exclusively locks the session-store item for which multiple concurrent requests are made. The default is false.
sessionLockingRetry	Optional Integer attribute. If enableSessionLocking is true and this integer is not less than 0, NCache Session Store Provider will return empty session after sessionLockingRetry, which specify the number of retries to acquire a lock. The default is -1.
writeExceptionsToEventLog	Optional Boolean attribute. If this flag is set, all the exceptions from cache API are written to event logs. The default is false.
enableLogs	Optional Boolean attribute. When this flag is set, store provider logs all error information. The log files are created in "$NCache-install/log-files/SessionStoreProvider/". The default is false.
enableDetailLogs	Optional Boolean attribute. When this flag is set, store provider logs all debugging information. The log files are created in "$NCache-install/log-files/SessionStoreProvider/". The default is false.
exceptionsEnabled	Optional Boolean attribute. Specifies whether exceptions from cache API are propagated to the page output. Setting this flag is especially helpful during development phase of application since exceptions provide more information about the specific causes of failure. The default is false.
operationRetry	It specifies the number of times server will retry the operation, in case connection is lost with a server while an operation is executing. Its default is zero.
operationRetryInterval	It specifies the time interval between each operation retry, in case connection is lost with the server. Its default value is zero.

Modify MachineKey Tag

Add <machineKey> entry under <system.web> section. It is required to generate ASP.NET session IDs in the same manner on all nodes. You can use the genmackeys utility available with NCache installation to generate the keys.

How to Fetch Session Data

NCache version 4.3 and later allow viewing all session data stored in clustered cache via NCache Session State Module. All session data is added in the specified cache as a tagged cache item with tag:"NC_ASP.net_session_data".

In order to retrieve previously stored session data, data can be fetched by GetByTag API, which returns Hashtable populated with session ids and associated session data stored in the cache.

Hashtable allSessionData = cache.GetByTag(

new Alachisoft.NCache.Runtime.Caching.Tag("NC_ASP.net_session_data"));

Enabling Location Affinity for SessionStoreProvider

Add New Section for Session State Management

Modify <configSections> section in the application's web.config and add following section.

For Enterprise and Professional Editions:-

<section name="ncache" type="Alachisoft.NCache.Web.SessionStateManagement.NCacheSection,

Alachisoft.NCache.SessionStateManagement, Version=x.x.x.x, Culture=neutral, PublicKeyToken=CFF5926ED6A53769"/>

</configSections>

For Open Source Edition:-

<section name="ncache" type="Alachisoft.NCache.Web.SessionStateManagement.NCacheSection,

Alachisoft.NCache.SessionStateManagement, Version=x.x.x.x, Culture=neutral, PublicKeyToken=1448e8d1123e9096"/>

</configSections>

Replace version "x.x.x.x" with the actual NCache version that you have.
Refer Alachisoft.NCache.SessionStateManagement in your project from "$NCache-install/bin/assembly/[2.0 or 4.0] folder.

Add a section with the section name specified above (<ncache> in this case), under <configuration> tag in your application's web.config.

</sessionLocation>

</ncache>

The sid-prefix is a unique identifier that is appended by custom session-ID manager in the beginning of session-ID. sid-prefix length must be equal to 4.

Modify sessionState Tag

Enable custom sessionID manager using the sessionIDManagerType attribute of the sessionState element in web.config and add custom provider.

Member	Description
sessionIDManagerType	Optional string attribute. Specifies an identifier to make sure that session ID remains unique in case multiple applications are using the same cache. Application ID should be same for an application in a web farm. If no app ID is specified, nothing will be concatenated with session ID.

When Location Affinity is enabled, cacheName specified in <providers> section of web.config will be ignored.
Cookieless sessions are not supported.