While upgrading Sitefinity 9.2.6230.0 PU to 11.0.6700.0 the below error is encountered:

System.ArgumentException: The value's length for key 'data source' exceeds it's limit of '128'. at Telerik.OpenAccess.RT.Adonet2Generic.Impl.DBDriver.connect(ConnectionString connectionString, PropertySet driverProps, ConnectionPoolType poolType, LogEventStore pes) at OpenAccessRuntime.Relational.sql.SqlDriver.InitializeFor(ConnectionString connectionString, Boolean noConnect, PropertySet props, DBDriver& driver, Connection& conn, ConnectionPoolType poolType) at OpenAccessRuntime.Relational.RelationalStorageManagerFactory..ctor(StorageManagerFactoryBuilder b) at OpenAccessRuntime.storagemanager.StorageManagerFactoryBuilder.createSmfForURL() ---> The value's length for key 'data source' exceeds it's limit of '128'.

Oracle database type is used.
The connection string is in the following format:

<connectionStrings>
    <add name="Sitefinity" connectionString="Data Source=(DESCRIPTION =(ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521)))(CONNECT_DATA = (SERVICE_NAME = orcl)));User Id=[userid];Password=[pass];" providerName="System.Data.OracleClient"  />
</connectionStrings>

 

The cause of the issue is that in the connection string there is no parameter indicating that the database is of type "Oracle" (dbtype/Backend). The default value for the dbtype/Backend parameter is "MsSql". OpenAccess is trying to validate the connection string for MsSQL database type.

1) If the connection string is located in the web.config file add a parameter Backend inside the connection string:

<connectionStrings>
    <add name="Sitefinity" connectionString="Data Source=(DESCRIPTION =(ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521)))(CONNECT_DATA = (SERVICE_NAME = orcl)));User Id=[userid];Password=[pass];Backend=Oracle" providerName="System.Data.OracleClient"  />
</connectionStrings>

2) By default, Sitefinity CMS stores the connection string to the database in the DataConfig.config file, located in folder ~/App_Data/Sitefinity/Configuration/. If the connection string is located in the web.config file, try moving it to the DataConfig.config. Add dbType attribute:

<connectionStrings>
    <add connectionString="Data Source=(DESCRIPTION =(ADDRESS_LIST =(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521)))(CONNECT_DATA = (SERVICE_NAME = orcl)));User Id=[userid];Password=[pass];" providerName="System.Data.OracleClient" dbType="Oracle" name="Sitefinity"/>
</connectionStrings>

3) If the connection string is already located in the DataConfig.config, add dbType="Oracle" attribute as per the example above.
 

Sitefinity documentation, Move the database connection string in the web.config file
https://www.progress.com/documentation/sitefinity-cms/administration-move-the-database-connection-string-in-the-web-config-file