Business Continuity Manager supports two types of routing rules, managed routing and passive routing.
Use managed routing rule when you need data synchronization. Use passive routing rule when running reports or when you do not need data synchronized.
The following table highlights the key differences between managed routing rule and passive routing rule.
| Managed Routing Rule | Passive Routing Rule |
|---|---|
| Sessions are opened on all available systems, per routing rule definition. The session open command is logged on the Recovery Log. | A session is opened on exactly one system, per passive routing rule definition. The session open command is not logged on the Recovery Log. |
| Sessions can only read and write to those objects that are managed and deployed in data dictionaries. |
|
| The Endpoint parses requests. | The Endpoint parses requests (so Business Continuity Manager can control writes to managed objects). |
| Requests go through Business Continuity Manager internal locking mechanism and are run by the Dispatcher after all locks are granted. Requests are logged on the Recovery Log. | Requests skip Business Continuity Manager internal locking and are sent to the Dispatcher, which then runs the requests against the database. Requests are not logged on the Recovery Log. |
| Error code-based retry/resubmit logic only works for read queries (with the limitation that the query is the first in an implicit transaction). Resubmit tries the query on another system where the connection is already open. | Error code-based retry/resubmit logic works for both read and write requests, regardless of transaction status and query count within the transaction. Resubmit closes the session on the current system, opens the session on another, and tries the query on that system. |
| A session is no longer available on a system if the system is no longer in the Active state in Business Continuity Manager. The session is recovered later when the system is active. | Once a passive session is opened on a system, the session remains active regardless of a change in the system state. If a return code indicates that the session is invalid (for example, due to system unavailability), the connection is moved to the next system per the routing rule/error code definitions. |
| Business Continuity Manager performs deadlock detection on managed sessions before the query is sent to the system. | Business Continuity Manager performs deadlock detection for passive sessions after the query is sent to the associated system. |
| Requests update the Transaction Table on the managed systems where the connection is open. | Requests do not update the Transaction Table on the managed system where the connection is open. |
| Loads and exports are allowed. |
|
| A session close request is logged on the Recovery Log. | A session close request is not logged on the Recovery Log. |