Data input routing after failure
Data associated with a plurality of transactions in a data replication system including first and second nodes connected via communication media in a topology is replicated. Each node includes a database and a replication engine which performs data replication functions between the first and second nodes. Each transaction is one or more transaction steps or transaction operations. One or more initial transaction steps or operations of a transaction are sent from an input device to a first node. The one or more initial transaction steps or operations of the transaction are sent to the second node via the replication engine at the first node. If a communication failure is detected between the input device and the first node, the input device sends the remaining transaction steps or operations to the second node. The remaining transaction steps or operations received at the second node are appended to the one or more initial transaction steps or operations received from the replication engine of the first node, thereby completing the transaction at the second node.
1. A method of replicating data associated with a plurality of transactions in a data replication system including first and second nodes connected via communication media in a topology, each node including (i) a database, (ii) a replication engine which performs data replication functions between the first and second nodes, each transaction being one or more transaction steps or transaction operations, the method comprising:
(a) sending one or more initial transaction steps or operations of a transaction from an input device to a first node;
(b) sending the one or more initial transaction steps or operations of the transaction to the second node via the replication engine at the first node;
(c) detecting a communication failure between the input device and the first node;
(d) upon detecting the communication failure, the input device sending the remaining transaction steps or operations to the second node; and
(e) appending the remaining transaction steps or operations received at the second node to the one or more initial transaction steps or operations received from the replication engine of the first node, thereby completing the transaction at the second node.
2. The method of claim 1 further comprising:
(f) sending the remaining transaction steps or operations to the first node via the replication engine of the second node.
3. The method of claim 2 further comprising:
(g) appending the remaining transaction steps or operations received from the replication engine of the second node to the initial transaction steps or operations previously received at the first node, thereby completing the transaction at the first node.
4. The method of claim 3 wherein step (g) is performed by the first node.
5. The method of claim 2 wherein step (f) is performed by the second node.
6. The method of claim 1 wherein step (e) is performed by the second node.
7. The method of claim 1 further comprising:
(f) completing the transaction at the second node without aborting the transaction at the second node.
8. The method of claim 1 wherein step (d) is performed without resending the initial transaction steps or operations to the second node.
9. An article of manufacture for replicating data associated with a plurality of transactions in a data replication system including first and second nodes connected via communication media in a topology, each node including (i) a database, (ii) a replication engine which performs data replication functions between the first and second nodes, each transaction being one or more transaction steps or transaction operations, the article of manufacture comprising a storage computer-readable medium encoded with computer-executable instructions for performing the steps of:
(a) sending one or more initial transaction steps or operations of a transaction from an input device to a first node;
(b) sending the one or more initial transaction steps or operations of the transaction to the second node via the replication engine at the first node;
(c) detecting a communication failure between the input device and the first node;
(d) upon detecting the communication failure, the input device sending the remaining transaction steps or operations to the second node; and
(e) appending the remaining transaction steps or operations received at the second node to the one or more initial transaction steps or operations received from the replication engine of the first node, thereby completing the transaction at the second node.
10. The article of manufacture of claim 9 further comprising:
(f) sending the remaining transaction steps or operations to the first node via the replication engine of the second node.
11. The article of manufacture of claim 10 further comprising:
(g) appending the remaining transaction steps or operations received from the replication engine of the second node to the initial transaction steps or operations previously received at the first node, thereby completing the transaction at the first node.
12. The article of manufacture of claim 11 wherein step (g) is performed by the first node.
13. The article of manufacture of claim 10 wherein step (f) is performed by the second node.
14. The article of manufacture of claim 9 wherein step (e) is performed by the second node.
15. The article of manufacture of claim 9 further comprising:
(f) completing the transaction at the second node without aborting the transaction at the second node.
16. The article of manufacture of claim 9 wherein step (d) is performed without resending the initial transaction steps or operations to the second node.