The vconfig element

To facilitate multi-tenancy on the C-Phrase Host, there is a virtual config element (vconfig) which lets you run NLIs which use a common .cphrase file, although with a different database connection specification. These virtual configurations, like regular configurations, have a set of corpus and parameter files, but when it loads the table definitions, it does so using a full config configuration specification. By changing the database usernames across a set of virtual configurations, you may run multiple tenants using the same core configuration and database.

<!ELEMENT vconfig>
<!ATTLIST vconfig
          id CDATA #REQUIRED
          db CDATA #REQUIRED
          configuration CDATA #IMPLIED>

id is the identifier of the virtual configuration. The folder and .cphrase and .py files associated with this configuration will all use this identifier.

db specifies how to connect to the underlying database. This is exactly as done with normal configurations.

configuration specifies which configuration should be used to define the tables, views, reports, etc. of the configuration that the virual configuration will be over.

As an example assume we have a full configuration FH that connects to a remote SQL Server database named 'fhistory'. Assume that users on that remote database are named reader1, reader2, ... and are configured to run as separate tenants. Given this, for the third tenant, assume we have a C-Phrase configuration with the name FH_T3 and within it the contents of the FH_T3.cphrase are exactly:

<vconfig id="FH_T3"

When you launch this configuration and the user connects to it, they will be operating as user reader3 and will thus run a tenant 3. Sharing NLI parameters, corpus files, etc. can be achieved via logging into the C-Phrase host, going to the configs directory and setting up symbolic links from tenant configuations into the main configuration directory.